src/share/classes/com/sun/tools/javac/comp/Attr.java

Thu, 24 May 2018 16:48:51 +0800

author
aoqi
date
Thu, 24 May 2018 16:48:51 +0800
changeset 3295
859dc787b52b
parent 3092
8c3890c90147
parent 2893
ca5783d9a597
permissions
-rw-r--r--

Merge

     1 /*
     2  * Copyright (c) 1999, 2016, Oracle and/or its affiliates. All rights reserved.
     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     4  *
     5  * This code is free software; you can redistribute it and/or modify it
     6  * under the terms of the GNU General Public License version 2 only, as
     7  * published by the Free Software Foundation.  Oracle designates this
     8  * particular file as subject to the "Classpath" exception as provided
     9  * by Oracle in the LICENSE file that accompanied this code.
    10  *
    11  * This code is distributed in the hope that it will be useful, but WITHOUT
    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    14  * version 2 for more details (a copy is included in the LICENSE file that
    15  * accompanied this code).
    16  *
    17  * You should have received a copy of the GNU General Public License version
    18  * 2 along with this work; if not, write to the Free Software Foundation,
    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
    20  *
    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
    22  * or visit www.oracle.com if you need additional information or have any
    23  * questions.
    24  */
    26 package com.sun.tools.javac.comp;
    28 import java.util.*;
    30 import javax.lang.model.element.ElementKind;
    31 import javax.tools.JavaFileObject;
    33 import com.sun.source.tree.IdentifierTree;
    34 import com.sun.source.tree.MemberReferenceTree.ReferenceMode;
    35 import com.sun.source.tree.MemberSelectTree;
    36 import com.sun.source.tree.TreeVisitor;
    37 import com.sun.source.util.SimpleTreeVisitor;
    38 import com.sun.tools.javac.code.*;
    39 import com.sun.tools.javac.code.Lint.LintCategory;
    40 import com.sun.tools.javac.code.Symbol.*;
    41 import com.sun.tools.javac.code.Type.*;
    42 import com.sun.tools.javac.comp.Check.CheckContext;
    43 import com.sun.tools.javac.comp.DeferredAttr.AttrMode;
    44 import com.sun.tools.javac.comp.Infer.InferenceContext;
    45 import com.sun.tools.javac.comp.Infer.FreeTypeListener;
    46 import com.sun.tools.javac.jvm.*;
    47 import com.sun.tools.javac.tree.*;
    48 import com.sun.tools.javac.tree.JCTree.*;
    49 import com.sun.tools.javac.tree.JCTree.JCPolyExpression.*;
    50 import com.sun.tools.javac.util.*;
    51 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
    52 import com.sun.tools.javac.util.List;
    53 import static com.sun.tools.javac.code.Flags.*;
    54 import static com.sun.tools.javac.code.Flags.ANNOTATION;
    55 import static com.sun.tools.javac.code.Flags.BLOCK;
    56 import static com.sun.tools.javac.code.Kinds.*;
    57 import static com.sun.tools.javac.code.Kinds.ERRONEOUS;
    58 import static com.sun.tools.javac.code.TypeTag.*;
    59 import static com.sun.tools.javac.code.TypeTag.WILDCARD;
    60 import static com.sun.tools.javac.tree.JCTree.Tag.*;
    62 /** This is the main context-dependent analysis phase in GJC. It
    63  *  encompasses name resolution, type checking and constant folding as
    64  *  subtasks. Some subtasks involve auxiliary classes.
    65  *  @see Check
    66  *  @see Resolve
    67  *  @see ConstFold
    68  *  @see Infer
    69  *
    70  *  <p><b>This is NOT part of any supported API.
    71  *  If you write code that depends on this, you do so at your own risk.
    72  *  This code and its internal interfaces are subject to change or
    73  *  deletion without notice.</b>
    74  */
    75 public class Attr extends JCTree.Visitor {
    76     protected static final Context.Key<Attr> attrKey =
    77         new Context.Key<Attr>();
    79     final Names names;
    80     final Log log;
    81     final Symtab syms;
    82     final Resolve rs;
    83     final Infer infer;
    84     final DeferredAttr deferredAttr;
    85     final Check chk;
    86     final Flow flow;
    87     final MemberEnter memberEnter;
    88     final TreeMaker make;
    89     final ConstFold cfolder;
    90     final Enter enter;
    91     final Target target;
    92     final Types types;
    93     final JCDiagnostic.Factory diags;
    94     final Annotate annotate;
    95     final TypeAnnotations typeAnnotations;
    96     final DeferredLintHandler deferredLintHandler;
    97     final TypeEnvs typeEnvs;
    99     public static Attr instance(Context context) {
   100         Attr instance = context.get(attrKey);
   101         if (instance == null)
   102             instance = new Attr(context);
   103         return instance;
   104     }
   106     protected Attr(Context context) {
   107         context.put(attrKey, this);
   109         names = Names.instance(context);
   110         log = Log.instance(context);
   111         syms = Symtab.instance(context);
   112         rs = Resolve.instance(context);
   113         chk = Check.instance(context);
   114         flow = Flow.instance(context);
   115         memberEnter = MemberEnter.instance(context);
   116         make = TreeMaker.instance(context);
   117         enter = Enter.instance(context);
   118         infer = Infer.instance(context);
   119         deferredAttr = DeferredAttr.instance(context);
   120         cfolder = ConstFold.instance(context);
   121         target = Target.instance(context);
   122         types = Types.instance(context);
   123         diags = JCDiagnostic.Factory.instance(context);
   124         annotate = Annotate.instance(context);
   125         typeAnnotations = TypeAnnotations.instance(context);
   126         deferredLintHandler = DeferredLintHandler.instance(context);
   127         typeEnvs = TypeEnvs.instance(context);
   129         Options options = Options.instance(context);
   131         Source source = Source.instance(context);
   132         allowGenerics = source.allowGenerics();
   133         allowVarargs = source.allowVarargs();
   134         allowEnums = source.allowEnums();
   135         allowBoxing = source.allowBoxing();
   136         allowCovariantReturns = source.allowCovariantReturns();
   137         allowAnonOuterThis = source.allowAnonOuterThis();
   138         allowStringsInSwitch = source.allowStringsInSwitch();
   139         allowPoly = source.allowPoly();
   140         allowTypeAnnos = source.allowTypeAnnotations();
   141         allowLambda = source.allowLambda();
   142         allowDefaultMethods = source.allowDefaultMethods();
   143         allowStaticInterfaceMethods = source.allowStaticInterfaceMethods();
   144         sourceName = source.name;
   145         relax = (options.isSet("-retrofit") ||
   146                  options.isSet("-relax"));
   147         findDiamonds = options.get("findDiamond") != null &&
   148                  source.allowDiamond();
   149         useBeforeDeclarationWarning = options.isSet("useBeforeDeclarationWarning");
   150         identifyLambdaCandidate = options.getBoolean("identifyLambdaCandidate", false);
   152         statInfo = new ResultInfo(NIL, Type.noType);
   153         varInfo = new ResultInfo(VAR, Type.noType);
   154         unknownExprInfo = new ResultInfo(VAL, Type.noType);
   155         unknownAnyPolyInfo = new ResultInfo(VAL, Infer.anyPoly);
   156         unknownTypeInfo = new ResultInfo(TYP, Type.noType);
   157         unknownTypeExprInfo = new ResultInfo(Kinds.TYP | Kinds.VAL, Type.noType);
   158         recoveryInfo = new RecoveryInfo(deferredAttr.emptyDeferredAttrContext);
   160         noCheckTree = make.at(-1).Skip();
   161     }
   163     /** Switch: relax some constraints for retrofit mode.
   164      */
   165     boolean relax;
   167     /** Switch: support target-typing inference
   168      */
   169     boolean allowPoly;
   171     /** Switch: support type annotations.
   172      */
   173     boolean allowTypeAnnos;
   175     /** Switch: support generics?
   176      */
   177     boolean allowGenerics;
   179     /** Switch: allow variable-arity methods.
   180      */
   181     boolean allowVarargs;
   183     /** Switch: support enums?
   184      */
   185     boolean allowEnums;
   187     /** Switch: support boxing and unboxing?
   188      */
   189     boolean allowBoxing;
   191     /** Switch: support covariant result types?
   192      */
   193     boolean allowCovariantReturns;
   195     /** Switch: support lambda expressions ?
   196      */
   197     boolean allowLambda;
   199     /** Switch: support default methods ?
   200      */
   201     boolean allowDefaultMethods;
   203     /** Switch: static interface methods enabled?
   204      */
   205     boolean allowStaticInterfaceMethods;
   207     /** Switch: allow references to surrounding object from anonymous
   208      * objects during constructor call?
   209      */
   210     boolean allowAnonOuterThis;
   212     /** Switch: generates a warning if diamond can be safely applied
   213      *  to a given new expression
   214      */
   215     boolean findDiamonds;
   217     /**
   218      * Internally enables/disables diamond finder feature
   219      */
   220     static final boolean allowDiamondFinder = true;
   222     /**
   223      * Switch: warn about use of variable before declaration?
   224      * RFE: 6425594
   225      */
   226     boolean useBeforeDeclarationWarning;
   228     /**
   229      * Switch: generate warnings whenever an anonymous inner class that is convertible
   230      * to a lambda expression is found
   231      */
   232     boolean identifyLambdaCandidate;
   234     /**
   235      * Switch: allow strings in switch?
   236      */
   237     boolean allowStringsInSwitch;
   239     /**
   240      * Switch: name of source level; used for error reporting.
   241      */
   242     String sourceName;
   244     /** Check kind and type of given tree against protokind and prototype.
   245      *  If check succeeds, store type in tree and return it.
   246      *  If check fails, store errType in tree and return it.
   247      *  No checks are performed if the prototype is a method type.
   248      *  It is not necessary in this case since we know that kind and type
   249      *  are correct.
   250      *
   251      *  @param tree     The tree whose kind and type is checked
   252      *  @param found    The computed type of the tree
   253      *  @param ownkind  The computed kind of the tree
   254      *  @param resultInfo  The expected result of the tree
   255      */
   256     Type check(final JCTree tree, final Type found, final int ownkind, final ResultInfo resultInfo) {
   257         InferenceContext inferenceContext = resultInfo.checkContext.inferenceContext();
   258         Type owntype;
   259         boolean shouldCheck = !found.hasTag(ERROR) &&
   260                 !resultInfo.pt.hasTag(METHOD) &&
   261                 !resultInfo.pt.hasTag(FORALL);
   262         if (shouldCheck && (ownkind & ~resultInfo.pkind) != 0) {
   263             log.error(tree.pos(), "unexpected.type",
   264                         kindNames(resultInfo.pkind),
   265                         kindName(ownkind));
   266             owntype = types.createErrorType(found);
   267         } else if (allowPoly && inferenceContext.free(found)) {
   268             //delay the check if there are inference variables in the found type
   269             //this means we are dealing with a partially inferred poly expression
   270             owntype = shouldCheck ? resultInfo.pt : found;
   271             inferenceContext.addFreeTypeListener(List.of(found, resultInfo.pt), new FreeTypeListener() {
   272                     @Override
   273                     public void typesInferred(InferenceContext inferenceContext) {
   274                         ResultInfo pendingResult =
   275                                 resultInfo.dup(inferenceContext.asInstType(resultInfo.pt));
   276                         check(tree, inferenceContext.asInstType(found), ownkind, pendingResult);
   277                     }
   278             });
   279         } else {
   280             owntype = shouldCheck ?
   281             resultInfo.check(tree, found) :
   282             found;
   283         }
   284         if (tree != noCheckTree) {
   285             tree.type = owntype;
   286         }
   287         return owntype;
   288     }
   290     /** Is given blank final variable assignable, i.e. in a scope where it
   291      *  may be assigned to even though it is final?
   292      *  @param v      The blank final variable.
   293      *  @param env    The current environment.
   294      */
   295     boolean isAssignableAsBlankFinal(VarSymbol v, Env<AttrContext> env) {
   296         Symbol owner = env.info.scope.owner;
   297            // owner refers to the innermost variable, method or
   298            // initializer block declaration at this point.
   299         return
   300             v.owner == owner
   301             ||
   302             ((owner.name == names.init ||    // i.e. we are in a constructor
   303               owner.kind == VAR ||           // i.e. we are in a variable initializer
   304               (owner.flags() & BLOCK) != 0)  // i.e. we are in an initializer block
   305              &&
   306              v.owner == owner.owner
   307              &&
   308              ((v.flags() & STATIC) != 0) == Resolve.isStatic(env));
   309     }
   311     /** Check that variable can be assigned to.
   312      *  @param pos    The current source code position.
   313      *  @param v      The assigned varaible
   314      *  @param base   If the variable is referred to in a Select, the part
   315      *                to the left of the `.', null otherwise.
   316      *  @param env    The current environment.
   317      */
   318     void checkAssignable(DiagnosticPosition pos, VarSymbol v, JCTree base, Env<AttrContext> env) {
   319         if ((v.flags() & FINAL) != 0 &&
   320             ((v.flags() & HASINIT) != 0
   321              ||
   322              !((base == null ||
   323                (base.hasTag(IDENT) && TreeInfo.name(base) == names._this)) &&
   324                isAssignableAsBlankFinal(v, env)))) {
   325             if (v.isResourceVariable()) { //TWR resource
   326                 log.error(pos, "try.resource.may.not.be.assigned", v);
   327             } else {
   328                 log.error(pos, "cant.assign.val.to.final.var", v);
   329             }
   330         }
   331     }
   333     /** Does tree represent a static reference to an identifier?
   334      *  It is assumed that tree is either a SELECT or an IDENT.
   335      *  We have to weed out selects from non-type names here.
   336      *  @param tree    The candidate tree.
   337      */
   338     boolean isStaticReference(JCTree tree) {
   339         if (tree.hasTag(SELECT)) {
   340             Symbol lsym = TreeInfo.symbol(((JCFieldAccess) tree).selected);
   341             if (lsym == null || lsym.kind != TYP) {
   342                 return false;
   343             }
   344         }
   345         return true;
   346     }
   348     /** Is this symbol a type?
   349      */
   350     static boolean isType(Symbol sym) {
   351         return sym != null && sym.kind == TYP;
   352     }
   354     /** The current `this' symbol.
   355      *  @param env    The current environment.
   356      */
   357     Symbol thisSym(DiagnosticPosition pos, Env<AttrContext> env) {
   358         return rs.resolveSelf(pos, env, env.enclClass.sym, names._this);
   359     }
   361     /** Attribute a parsed identifier.
   362      * @param tree Parsed identifier name
   363      * @param topLevel The toplevel to use
   364      */
   365     public Symbol attribIdent(JCTree tree, JCCompilationUnit topLevel) {
   366         Env<AttrContext> localEnv = enter.topLevelEnv(topLevel);
   367         localEnv.enclClass = make.ClassDef(make.Modifiers(0),
   368                                            syms.errSymbol.name,
   369                                            null, null, null, null);
   370         localEnv.enclClass.sym = syms.errSymbol;
   371         return tree.accept(identAttributer, localEnv);
   372     }
   373     // where
   374         private TreeVisitor<Symbol,Env<AttrContext>> identAttributer = new IdentAttributer();
   375         private class IdentAttributer extends SimpleTreeVisitor<Symbol,Env<AttrContext>> {
   376             @Override
   377             public Symbol visitMemberSelect(MemberSelectTree node, Env<AttrContext> env) {
   378                 Symbol site = visit(node.getExpression(), env);
   379                 if (site.kind == ERR || site.kind == ABSENT_TYP)
   380                     return site;
   381                 Name name = (Name)node.getIdentifier();
   382                 if (site.kind == PCK) {
   383                     env.toplevel.packge = (PackageSymbol)site;
   384                     return rs.findIdentInPackage(env, (TypeSymbol)site, name, TYP | PCK);
   385                 } else {
   386                     env.enclClass.sym = (ClassSymbol)site;
   387                     return rs.findMemberType(env, site.asType(), name, (TypeSymbol)site);
   388                 }
   389             }
   391             @Override
   392             public Symbol visitIdentifier(IdentifierTree node, Env<AttrContext> env) {
   393                 return rs.findIdent(env, (Name)node.getName(), TYP | PCK);
   394             }
   395         }
   397     public Type coerce(Type etype, Type ttype) {
   398         return cfolder.coerce(etype, ttype);
   399     }
   401     public Type attribType(JCTree node, TypeSymbol sym) {
   402         Env<AttrContext> env = typeEnvs.get(sym);
   403         Env<AttrContext> localEnv = env.dup(node, env.info.dup());
   404         return attribTree(node, localEnv, unknownTypeInfo);
   405     }
   407     public Type attribImportQualifier(JCImport tree, Env<AttrContext> env) {
   408         // Attribute qualifying package or class.
   409         JCFieldAccess s = (JCFieldAccess)tree.qualid;
   410         return attribTree(s.selected,
   411                        env,
   412                        new ResultInfo(tree.staticImport ? TYP : (TYP | PCK),
   413                        Type.noType));
   414     }
   416     public Env<AttrContext> attribExprToTree(JCTree expr, Env<AttrContext> env, JCTree tree) {
   417         breakTree = tree;
   418         JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
   419         try {
   420             attribExpr(expr, env);
   421         } catch (BreakAttr b) {
   422             return b.env;
   423         } catch (AssertionError ae) {
   424             if (ae.getCause() instanceof BreakAttr) {
   425                 return ((BreakAttr)(ae.getCause())).env;
   426             } else {
   427                 throw ae;
   428             }
   429         } finally {
   430             breakTree = null;
   431             log.useSource(prev);
   432         }
   433         return env;
   434     }
   436     public Env<AttrContext> attribStatToTree(JCTree stmt, Env<AttrContext> env, JCTree tree) {
   437         breakTree = tree;
   438         JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
   439         try {
   440             attribStat(stmt, env);
   441         } catch (BreakAttr b) {
   442             return b.env;
   443         } catch (AssertionError ae) {
   444             if (ae.getCause() instanceof BreakAttr) {
   445                 return ((BreakAttr)(ae.getCause())).env;
   446             } else {
   447                 throw ae;
   448             }
   449         } finally {
   450             breakTree = null;
   451             log.useSource(prev);
   452         }
   453         return env;
   454     }
   456     private JCTree breakTree = null;
   458     private static class BreakAttr extends RuntimeException {
   459         static final long serialVersionUID = -6924771130405446405L;
   460         private Env<AttrContext> env;
   461         private BreakAttr(Env<AttrContext> env) {
   462             this.env = env;
   463         }
   464     }
   466     class ResultInfo {
   467         final int pkind;
   468         final Type pt;
   469         final CheckContext checkContext;
   471         ResultInfo(int pkind, Type pt) {
   472             this(pkind, pt, chk.basicHandler);
   473         }
   475         protected ResultInfo(int pkind, Type pt, CheckContext checkContext) {
   476             this.pkind = pkind;
   477             this.pt = pt;
   478             this.checkContext = checkContext;
   479         }
   481         protected Type check(final DiagnosticPosition pos, final Type found) {
   482             return chk.checkType(pos, found, pt, checkContext);
   483         }
   485         protected ResultInfo dup(Type newPt) {
   486             return new ResultInfo(pkind, newPt, checkContext);
   487         }
   489         protected ResultInfo dup(CheckContext newContext) {
   490             return new ResultInfo(pkind, pt, newContext);
   491         }
   493         protected ResultInfo dup(Type newPt, CheckContext newContext) {
   494             return new ResultInfo(pkind, newPt, newContext);
   495         }
   497         @Override
   498         public String toString() {
   499             if (pt != null) {
   500                 return pt.toString();
   501             } else {
   502                 return "";
   503             }
   504         }
   505     }
   507     class RecoveryInfo extends ResultInfo {
   509         public RecoveryInfo(final DeferredAttr.DeferredAttrContext deferredAttrContext) {
   510             super(Kinds.VAL, Type.recoveryType, new Check.NestedCheckContext(chk.basicHandler) {
   511                 @Override
   512                 public DeferredAttr.DeferredAttrContext deferredAttrContext() {
   513                     return deferredAttrContext;
   514                 }
   515                 @Override
   516                 public boolean compatible(Type found, Type req, Warner warn) {
   517                     return true;
   518                 }
   519                 @Override
   520                 public void report(DiagnosticPosition pos, JCDiagnostic details) {
   521                     chk.basicHandler.report(pos, details);
   522                 }
   523             });
   524         }
   525     }
   527     final ResultInfo statInfo;
   528     final ResultInfo varInfo;
   529     final ResultInfo unknownAnyPolyInfo;
   530     final ResultInfo unknownExprInfo;
   531     final ResultInfo unknownTypeInfo;
   532     final ResultInfo unknownTypeExprInfo;
   533     final ResultInfo recoveryInfo;
   535     Type pt() {
   536         return resultInfo.pt;
   537     }
   539     int pkind() {
   540         return resultInfo.pkind;
   541     }
   543 /* ************************************************************************
   544  * Visitor methods
   545  *************************************************************************/
   547     /** Visitor argument: the current environment.
   548      */
   549     Env<AttrContext> env;
   551     /** Visitor argument: the currently expected attribution result.
   552      */
   553     ResultInfo resultInfo;
   555     /** Visitor result: the computed type.
   556      */
   557     Type result;
   559     /** Synthetic tree to be used during 'fake' checks.
   560      */
   561     JCTree noCheckTree;
   563     /** Visitor method: attribute a tree, catching any completion failure
   564      *  exceptions. Return the tree's type.
   565      *
   566      *  @param tree    The tree to be visited.
   567      *  @param env     The environment visitor argument.
   568      *  @param resultInfo   The result info visitor argument.
   569      */
   570     Type attribTree(JCTree tree, Env<AttrContext> env, ResultInfo resultInfo) {
   571         Env<AttrContext> prevEnv = this.env;
   572         ResultInfo prevResult = this.resultInfo;
   573         try {
   574             this.env = env;
   575             this.resultInfo = resultInfo;
   576             tree.accept(this);
   577             if (tree == breakTree &&
   578                     resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) {
   579                 throw new BreakAttr(copyEnv(env));
   580             }
   581             return result;
   582         } catch (CompletionFailure ex) {
   583             tree.type = syms.errType;
   584             return chk.completionError(tree.pos(), ex);
   585         } finally {
   586             this.env = prevEnv;
   587             this.resultInfo = prevResult;
   588         }
   589     }
   591     Env<AttrContext> copyEnv(Env<AttrContext> env) {
   592         Env<AttrContext> newEnv =
   593                 env.dup(env.tree, env.info.dup(copyScope(env.info.scope)));
   594         if (newEnv.outer != null) {
   595             newEnv.outer = copyEnv(newEnv.outer);
   596         }
   597         return newEnv;
   598     }
   600     Scope copyScope(Scope sc) {
   601         Scope newScope = new Scope(sc.owner);
   602         List<Symbol> elemsList = List.nil();
   603         while (sc != null) {
   604             for (Scope.Entry e = sc.elems ; e != null ; e = e.sibling) {
   605                 elemsList = elemsList.prepend(e.sym);
   606             }
   607             sc = sc.next;
   608         }
   609         for (Symbol s : elemsList) {
   610             newScope.enter(s);
   611         }
   612         return newScope;
   613     }
   615     /** Derived visitor method: attribute an expression tree.
   616      */
   617     public Type attribExpr(JCTree tree, Env<AttrContext> env, Type pt) {
   618         return attribTree(tree, env, new ResultInfo(VAL, !pt.hasTag(ERROR) ? pt : Type.noType));
   619     }
   621     /** Derived visitor method: attribute an expression tree with
   622      *  no constraints on the computed type.
   623      */
   624     public Type attribExpr(JCTree tree, Env<AttrContext> env) {
   625         return attribTree(tree, env, unknownExprInfo);
   626     }
   628     /** Derived visitor method: attribute a type tree.
   629      */
   630     public Type attribType(JCTree tree, Env<AttrContext> env) {
   631         Type result = attribType(tree, env, Type.noType);
   632         return result;
   633     }
   635     /** Derived visitor method: attribute a type tree.
   636      */
   637     Type attribType(JCTree tree, Env<AttrContext> env, Type pt) {
   638         Type result = attribTree(tree, env, new ResultInfo(TYP, pt));
   639         return result;
   640     }
   642     /** Derived visitor method: attribute a statement or definition tree.
   643      */
   644     public Type attribStat(JCTree tree, Env<AttrContext> env) {
   645         return attribTree(tree, env, statInfo);
   646     }
   648     /** Attribute a list of expressions, returning a list of types.
   649      */
   650     List<Type> attribExprs(List<JCExpression> trees, Env<AttrContext> env, Type pt) {
   651         ListBuffer<Type> ts = new ListBuffer<Type>();
   652         for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
   653             ts.append(attribExpr(l.head, env, pt));
   654         return ts.toList();
   655     }
   657     /** Attribute a list of statements, returning nothing.
   658      */
   659     <T extends JCTree> void attribStats(List<T> trees, Env<AttrContext> env) {
   660         for (List<T> l = trees; l.nonEmpty(); l = l.tail)
   661             attribStat(l.head, env);
   662     }
   664     /** Attribute the arguments in a method call, returning the method kind.
   665      */
   666     int attribArgs(int initialKind, List<JCExpression> trees, Env<AttrContext> env, ListBuffer<Type> argtypes) {
   667         int kind = initialKind;
   668         for (JCExpression arg : trees) {
   669             Type argtype;
   670             if (allowPoly && deferredAttr.isDeferred(env, arg)) {
   671                 argtype = deferredAttr.new DeferredType(arg, env);
   672                 kind |= POLY;
   673             } else {
   674                 argtype = chk.checkNonVoid(arg, attribTree(arg, env, unknownAnyPolyInfo));
   675             }
   676             argtypes.append(argtype);
   677         }
   678         return kind;
   679     }
   681     /** Attribute a type argument list, returning a list of types.
   682      *  Caller is responsible for calling checkRefTypes.
   683      */
   684     List<Type> attribAnyTypes(List<JCExpression> trees, Env<AttrContext> env) {
   685         ListBuffer<Type> argtypes = new ListBuffer<Type>();
   686         for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
   687             argtypes.append(attribType(l.head, env));
   688         return argtypes.toList();
   689     }
   691     /** Attribute a type argument list, returning a list of types.
   692      *  Check that all the types are references.
   693      */
   694     List<Type> attribTypes(List<JCExpression> trees, Env<AttrContext> env) {
   695         List<Type> types = attribAnyTypes(trees, env);
   696         return chk.checkRefTypes(trees, types);
   697     }
   699     /**
   700      * Attribute type variables (of generic classes or methods).
   701      * Compound types are attributed later in attribBounds.
   702      * @param typarams the type variables to enter
   703      * @param env      the current environment
   704      */
   705     void attribTypeVariables(List<JCTypeParameter> typarams, Env<AttrContext> env) {
   706         for (JCTypeParameter tvar : typarams) {
   707             TypeVar a = (TypeVar)tvar.type;
   708             a.tsym.flags_field |= UNATTRIBUTED;
   709             a.bound = Type.noType;
   710             if (!tvar.bounds.isEmpty()) {
   711                 List<Type> bounds = List.of(attribType(tvar.bounds.head, env));
   712                 for (JCExpression bound : tvar.bounds.tail)
   713                     bounds = bounds.prepend(attribType(bound, env));
   714                 types.setBounds(a, bounds.reverse());
   715             } else {
   716                 // if no bounds are given, assume a single bound of
   717                 // java.lang.Object.
   718                 types.setBounds(a, List.of(syms.objectType));
   719             }
   720             a.tsym.flags_field &= ~UNATTRIBUTED;
   721         }
   722         for (JCTypeParameter tvar : typarams) {
   723             chk.checkNonCyclic(tvar.pos(), (TypeVar)tvar.type);
   724         }
   725     }
   727     /**
   728      * Attribute the type references in a list of annotations.
   729      */
   730     void attribAnnotationTypes(List<JCAnnotation> annotations,
   731                                Env<AttrContext> env) {
   732         for (List<JCAnnotation> al = annotations; al.nonEmpty(); al = al.tail) {
   733             JCAnnotation a = al.head;
   734             attribType(a.annotationType, env);
   735         }
   736     }
   738     /**
   739      * Attribute a "lazy constant value".
   740      *  @param env         The env for the const value
   741      *  @param initializer The initializer for the const value
   742      *  @param type        The expected type, or null
   743      *  @see VarSymbol#setLazyConstValue
   744      */
   745     public Object attribLazyConstantValue(Env<AttrContext> env,
   746                                       JCVariableDecl variable,
   747                                       Type type) {
   749         DiagnosticPosition prevLintPos
   750                 = deferredLintHandler.setPos(variable.pos());
   752         try {
   753             // Use null as symbol to not attach the type annotation to any symbol.
   754             // The initializer will later also be visited and then we'll attach
   755             // to the symbol.
   756             // This prevents having multiple type annotations, just because of
   757             // lazy constant value evaluation.
   758             memberEnter.typeAnnotate(variable.init, env, null, variable.pos());
   759             annotate.flush();
   760             Type itype = attribExpr(variable.init, env, type);
   761             if (itype.constValue() != null) {
   762                 return coerce(itype, type).constValue();
   763             } else {
   764                 return null;
   765             }
   766         } finally {
   767             deferredLintHandler.setPos(prevLintPos);
   768         }
   769     }
   771     /** Attribute type reference in an `extends' or `implements' clause.
   772      *  Supertypes of anonymous inner classes are usually already attributed.
   773      *
   774      *  @param tree              The tree making up the type reference.
   775      *  @param env               The environment current at the reference.
   776      *  @param classExpected     true if only a class is expected here.
   777      *  @param interfaceExpected true if only an interface is expected here.
   778      */
   779     Type attribBase(JCTree tree,
   780                     Env<AttrContext> env,
   781                     boolean classExpected,
   782                     boolean interfaceExpected,
   783                     boolean checkExtensible) {
   784         Type t = tree.type != null ?
   785             tree.type :
   786             attribType(tree, env);
   787         return checkBase(t, tree, env, classExpected, interfaceExpected, checkExtensible);
   788     }
   789     Type checkBase(Type t,
   790                    JCTree tree,
   791                    Env<AttrContext> env,
   792                    boolean classExpected,
   793                    boolean interfaceExpected,
   794                    boolean checkExtensible) {
   795         if (t.tsym.isAnonymous()) {
   796             log.error(tree.pos(), "cant.inherit.from.anon");
   797             return types.createErrorType(t);
   798         }
   799         if (t.isErroneous())
   800             return t;
   801         if (t.hasTag(TYPEVAR) && !classExpected && !interfaceExpected) {
   802             // check that type variable is already visible
   803             if (t.getUpperBound() == null) {
   804                 log.error(tree.pos(), "illegal.forward.ref");
   805                 return types.createErrorType(t);
   806             }
   807         } else {
   808             t = chk.checkClassType(tree.pos(), t, checkExtensible|!allowGenerics);
   809         }
   810         if (interfaceExpected && (t.tsym.flags() & INTERFACE) == 0) {
   811             log.error(tree.pos(), "intf.expected.here");
   812             // return errType is necessary since otherwise there might
   813             // be undetected cycles which cause attribution to loop
   814             return types.createErrorType(t);
   815         } else if (checkExtensible &&
   816                    classExpected &&
   817                    (t.tsym.flags() & INTERFACE) != 0) {
   818             log.error(tree.pos(), "no.intf.expected.here");
   819             return types.createErrorType(t);
   820         }
   821         if (checkExtensible &&
   822             ((t.tsym.flags() & FINAL) != 0)) {
   823             log.error(tree.pos(),
   824                       "cant.inherit.from.final", t.tsym);
   825         }
   826         chk.checkNonCyclic(tree.pos(), t);
   827         return t;
   828     }
   830     Type attribIdentAsEnumType(Env<AttrContext> env, JCIdent id) {
   831         Assert.check((env.enclClass.sym.flags() & ENUM) != 0);
   832         id.type = env.info.scope.owner.type;
   833         id.sym = env.info.scope.owner;
   834         return id.type;
   835     }
   837     public void visitClassDef(JCClassDecl tree) {
   838         // Local and anonymous classes have not been entered yet, so we need to
   839         // do it now.
   840         if ((env.info.scope.owner.kind & (VAR | MTH)) != 0) {
   841             enter.classEnter(tree, env);
   842         } else {
   843             // If this class declaration is part of a class level annotation,
   844             // as in @MyAnno(new Object() {}) class MyClass {}, enter it in
   845             // order to simplify later steps and allow for sensible error
   846             // messages.
   847             if (env.tree.hasTag(NEWCLASS) && TreeInfo.isInAnnotation(env, tree))
   848                 enter.classEnter(tree, env);
   849         }
   851         ClassSymbol c = tree.sym;
   852         if (c == null) {
   853             // exit in case something drastic went wrong during enter.
   854             result = null;
   855         } else {
   856             // make sure class has been completed:
   857             c.complete();
   859             // If this class appears as an anonymous class
   860             // in a superclass constructor call where
   861             // no explicit outer instance is given,
   862             // disable implicit outer instance from being passed.
   863             // (This would be an illegal access to "this before super").
   864             if (env.info.isSelfCall &&
   865                 env.tree.hasTag(NEWCLASS) &&
   866                 ((JCNewClass) env.tree).encl == null)
   867             {
   868                 c.flags_field |= NOOUTERTHIS;
   869             }
   870             attribClass(tree.pos(), c);
   871             result = tree.type = c.type;
   872         }
   873     }
   875     public void visitMethodDef(JCMethodDecl tree) {
   876         MethodSymbol m = tree.sym;
   877         boolean isDefaultMethod = (m.flags() & DEFAULT) != 0;
   879         Lint lint = env.info.lint.augment(m);
   880         Lint prevLint = chk.setLint(lint);
   881         MethodSymbol prevMethod = chk.setMethod(m);
   882         try {
   883             deferredLintHandler.flush(tree.pos());
   884             chk.checkDeprecatedAnnotation(tree.pos(), m);
   887             // Create a new environment with local scope
   888             // for attributing the method.
   889             Env<AttrContext> localEnv = memberEnter.methodEnv(tree, env);
   890             localEnv.info.lint = lint;
   892             attribStats(tree.typarams, localEnv);
   894             // If we override any other methods, check that we do so properly.
   895             // JLS ???
   896             if (m.isStatic()) {
   897                 chk.checkHideClashes(tree.pos(), env.enclClass.type, m);
   898             } else {
   899                 chk.checkOverrideClashes(tree.pos(), env.enclClass.type, m);
   900             }
   901             chk.checkOverride(tree, m);
   903             if (isDefaultMethod && types.overridesObjectMethod(m.enclClass(), m)) {
   904                 log.error(tree, "default.overrides.object.member", m.name, Kinds.kindName(m.location()), m.location());
   905             }
   907             // Enter all type parameters into the local method scope.
   908             for (List<JCTypeParameter> l = tree.typarams; l.nonEmpty(); l = l.tail)
   909                 localEnv.info.scope.enterIfAbsent(l.head.type.tsym);
   911             ClassSymbol owner = env.enclClass.sym;
   912             if ((owner.flags() & ANNOTATION) != 0 &&
   913                 tree.params.nonEmpty())
   914                 log.error(tree.params.head.pos(),
   915                           "intf.annotation.members.cant.have.params");
   917             // Attribute all value parameters.
   918             for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) {
   919                 attribStat(l.head, localEnv);
   920             }
   922             chk.checkVarargsMethodDecl(localEnv, tree);
   924             // Check that type parameters are well-formed.
   925             chk.validate(tree.typarams, localEnv);
   927             // Check that result type is well-formed.
   928             if (tree.restype != null && !tree.restype.type.hasTag(VOID))
   929                 chk.validate(tree.restype, localEnv);
   931             // Check that receiver type is well-formed.
   932             if (tree.recvparam != null) {
   933                 // Use a new environment to check the receiver parameter.
   934                 // Otherwise I get "might not have been initialized" errors.
   935                 // Is there a better way?
   936                 Env<AttrContext> newEnv = memberEnter.methodEnv(tree, env);
   937                 attribType(tree.recvparam, newEnv);
   938                 chk.validate(tree.recvparam, newEnv);
   939             }
   941             // annotation method checks
   942             if ((owner.flags() & ANNOTATION) != 0) {
   943                 // annotation method cannot have throws clause
   944                 if (tree.thrown.nonEmpty()) {
   945                     log.error(tree.thrown.head.pos(),
   946                             "throws.not.allowed.in.intf.annotation");
   947                 }
   948                 // annotation method cannot declare type-parameters
   949                 if (tree.typarams.nonEmpty()) {
   950                     log.error(tree.typarams.head.pos(),
   951                             "intf.annotation.members.cant.have.type.params");
   952                 }
   953                 // validate annotation method's return type (could be an annotation type)
   954                 chk.validateAnnotationType(tree.restype);
   955                 // ensure that annotation method does not clash with members of Object/Annotation
   956                 chk.validateAnnotationMethod(tree.pos(), m);
   957             }
   959             for (List<JCExpression> l = tree.thrown; l.nonEmpty(); l = l.tail)
   960                 chk.checkType(l.head.pos(), l.head.type, syms.throwableType);
   962             if (tree.body == null) {
   963                 // Empty bodies are only allowed for
   964                 // abstract, native, or interface methods, or for methods
   965                 // in a retrofit signature class.
   966                 if (isDefaultMethod || (tree.sym.flags() & (ABSTRACT | NATIVE)) == 0 &&
   967                     !relax)
   968                     log.error(tree.pos(), "missing.meth.body.or.decl.abstract");
   969                 if (tree.defaultValue != null) {
   970                     if ((owner.flags() & ANNOTATION) == 0)
   971                         log.error(tree.pos(),
   972                                   "default.allowed.in.intf.annotation.member");
   973                 }
   974             } else if ((tree.sym.flags() & ABSTRACT) != 0 && !isDefaultMethod) {
   975                 if ((owner.flags() & INTERFACE) != 0) {
   976                     log.error(tree.body.pos(), "intf.meth.cant.have.body");
   977                 } else {
   978                     log.error(tree.pos(), "abstract.meth.cant.have.body");
   979                 }
   980             } else if ((tree.mods.flags & NATIVE) != 0) {
   981                 log.error(tree.pos(), "native.meth.cant.have.body");
   982             } else {
   983                 // Add an implicit super() call unless an explicit call to
   984                 // super(...) or this(...) is given
   985                 // or we are compiling class java.lang.Object.
   986                 if (tree.name == names.init && owner.type != syms.objectType) {
   987                     JCBlock body = tree.body;
   988                     if (body.stats.isEmpty() ||
   989                         !TreeInfo.isSelfCall(body.stats.head)) {
   990                         body.stats = body.stats.
   991                             prepend(memberEnter.SuperCall(make.at(body.pos),
   992                                                           List.<Type>nil(),
   993                                                           List.<JCVariableDecl>nil(),
   994                                                           false));
   995                     } else if ((env.enclClass.sym.flags() & ENUM) != 0 &&
   996                                (tree.mods.flags & GENERATEDCONSTR) == 0 &&
   997                                TreeInfo.isSuperCall(body.stats.head)) {
   998                         // enum constructors are not allowed to call super
   999                         // directly, so make sure there aren't any super calls
  1000                         // in enum constructors, except in the compiler
  1001                         // generated one.
  1002                         log.error(tree.body.stats.head.pos(),
  1003                                   "call.to.super.not.allowed.in.enum.ctor",
  1004                                   env.enclClass.sym);
  1008                 // Attribute all type annotations in the body
  1009                 memberEnter.typeAnnotate(tree.body, localEnv, m, null);
  1010                 annotate.flush();
  1012                 // Attribute method body.
  1013                 attribStat(tree.body, localEnv);
  1016             localEnv.info.scope.leave();
  1017             result = tree.type = m.type;
  1019         finally {
  1020             chk.setLint(prevLint);
  1021             chk.setMethod(prevMethod);
  1025     public void visitVarDef(JCVariableDecl tree) {
  1026         // Local variables have not been entered yet, so we need to do it now:
  1027         if (env.info.scope.owner.kind == MTH) {
  1028             if (tree.sym != null) {
  1029                 // parameters have already been entered
  1030                 env.info.scope.enter(tree.sym);
  1031             } else {
  1032                 try {
  1033                     annotate.enterStart();
  1034                     memberEnter.memberEnter(tree, env);
  1035                 } finally {
  1036                     annotate.enterDone();
  1039         } else {
  1040             if (tree.init != null) {
  1041                 // Field initializer expression need to be entered.
  1042                 memberEnter.typeAnnotate(tree.init, env, tree.sym, tree.pos());
  1043                 annotate.flush();
  1047         VarSymbol v = tree.sym;
  1048         Lint lint = env.info.lint.augment(v);
  1049         Lint prevLint = chk.setLint(lint);
  1051         // Check that the variable's declared type is well-formed.
  1052         boolean isImplicitLambdaParameter = env.tree.hasTag(LAMBDA) &&
  1053                 ((JCLambda)env.tree).paramKind == JCLambda.ParameterKind.IMPLICIT &&
  1054                 (tree.sym.flags() & PARAMETER) != 0;
  1055         chk.validate(tree.vartype, env, !isImplicitLambdaParameter);
  1057         try {
  1058             v.getConstValue(); // ensure compile-time constant initializer is evaluated
  1059             deferredLintHandler.flush(tree.pos());
  1060             chk.checkDeprecatedAnnotation(tree.pos(), v);
  1062             if (tree.init != null) {
  1063                 if ((v.flags_field & FINAL) == 0 ||
  1064                     !memberEnter.needsLazyConstValue(tree.init)) {
  1065                     // Not a compile-time constant
  1066                     // Attribute initializer in a new environment
  1067                     // with the declared variable as owner.
  1068                     // Check that initializer conforms to variable's declared type.
  1069                     Env<AttrContext> initEnv = memberEnter.initEnv(tree, env);
  1070                     initEnv.info.lint = lint;
  1071                     // In order to catch self-references, we set the variable's
  1072                     // declaration position to maximal possible value, effectively
  1073                     // marking the variable as undefined.
  1074                     initEnv.info.enclVar = v;
  1075                     attribExpr(tree.init, initEnv, v.type);
  1078             result = tree.type = v.type;
  1080         finally {
  1081             chk.setLint(prevLint);
  1085     public void visitSkip(JCSkip tree) {
  1086         result = null;
  1089     public void visitBlock(JCBlock tree) {
  1090         if (env.info.scope.owner.kind == TYP) {
  1091             // Block is a static or instance initializer;
  1092             // let the owner of the environment be a freshly
  1093             // created BLOCK-method.
  1094             Env<AttrContext> localEnv =
  1095                 env.dup(tree, env.info.dup(env.info.scope.dupUnshared()));
  1096             localEnv.info.scope.owner =
  1097                 new MethodSymbol(tree.flags | BLOCK |
  1098                     env.info.scope.owner.flags() & STRICTFP, names.empty, null,
  1099                     env.info.scope.owner);
  1100             if ((tree.flags & STATIC) != 0) localEnv.info.staticLevel++;
  1102             // Attribute all type annotations in the block
  1103             memberEnter.typeAnnotate(tree, localEnv, localEnv.info.scope.owner, null);
  1104             annotate.flush();
  1107                 // Store init and clinit type annotations with the ClassSymbol
  1108                 // to allow output in Gen.normalizeDefs.
  1109                 ClassSymbol cs = (ClassSymbol)env.info.scope.owner;
  1110                 List<Attribute.TypeCompound> tas = localEnv.info.scope.owner.getRawTypeAttributes();
  1111                 if ((tree.flags & STATIC) != 0) {
  1112                     cs.appendClassInitTypeAttributes(tas);
  1113                 } else {
  1114                     cs.appendInitTypeAttributes(tas);
  1118             attribStats(tree.stats, localEnv);
  1119         } else {
  1120             // Create a new local environment with a local scope.
  1121             Env<AttrContext> localEnv =
  1122                 env.dup(tree, env.info.dup(env.info.scope.dup()));
  1123             try {
  1124                 attribStats(tree.stats, localEnv);
  1125             } finally {
  1126                 localEnv.info.scope.leave();
  1129         result = null;
  1132     public void visitDoLoop(JCDoWhileLoop tree) {
  1133         attribStat(tree.body, env.dup(tree));
  1134         attribExpr(tree.cond, env, syms.booleanType);
  1135         result = null;
  1138     public void visitWhileLoop(JCWhileLoop tree) {
  1139         attribExpr(tree.cond, env, syms.booleanType);
  1140         attribStat(tree.body, env.dup(tree));
  1141         result = null;
  1144     public void visitForLoop(JCForLoop tree) {
  1145         Env<AttrContext> loopEnv =
  1146             env.dup(env.tree, env.info.dup(env.info.scope.dup()));
  1147         try {
  1148             attribStats(tree.init, loopEnv);
  1149             if (tree.cond != null) attribExpr(tree.cond, loopEnv, syms.booleanType);
  1150             loopEnv.tree = tree; // before, we were not in loop!
  1151             attribStats(tree.step, loopEnv);
  1152             attribStat(tree.body, loopEnv);
  1153             result = null;
  1155         finally {
  1156             loopEnv.info.scope.leave();
  1160     public void visitForeachLoop(JCEnhancedForLoop tree) {
  1161         Env<AttrContext> loopEnv =
  1162             env.dup(env.tree, env.info.dup(env.info.scope.dup()));
  1163         try {
  1164             //the Formal Parameter of a for-each loop is not in the scope when
  1165             //attributing the for-each expression; we mimick this by attributing
  1166             //the for-each expression first (against original scope).
  1167             Type exprType = types.cvarUpperBound(attribExpr(tree.expr, loopEnv));
  1168             attribStat(tree.var, loopEnv);
  1169             chk.checkNonVoid(tree.pos(), exprType);
  1170             Type elemtype = types.elemtype(exprType); // perhaps expr is an array?
  1171             if (elemtype == null) {
  1172                 // or perhaps expr implements Iterable<T>?
  1173                 Type base = types.asSuper(exprType, syms.iterableType.tsym);
  1174                 if (base == null) {
  1175                     log.error(tree.expr.pos(),
  1176                             "foreach.not.applicable.to.type",
  1177                             exprType,
  1178                             diags.fragment("type.req.array.or.iterable"));
  1179                     elemtype = types.createErrorType(exprType);
  1180                 } else {
  1181                     List<Type> iterableParams = base.allparams();
  1182                     elemtype = iterableParams.isEmpty()
  1183                         ? syms.objectType
  1184                         : types.wildUpperBound(iterableParams.head);
  1187             chk.checkType(tree.expr.pos(), elemtype, tree.var.sym.type);
  1188             loopEnv.tree = tree; // before, we were not in loop!
  1189             attribStat(tree.body, loopEnv);
  1190             result = null;
  1192         finally {
  1193             loopEnv.info.scope.leave();
  1197     public void visitLabelled(JCLabeledStatement tree) {
  1198         // Check that label is not used in an enclosing statement
  1199         Env<AttrContext> env1 = env;
  1200         while (env1 != null && !env1.tree.hasTag(CLASSDEF)) {
  1201             if (env1.tree.hasTag(LABELLED) &&
  1202                 ((JCLabeledStatement) env1.tree).label == tree.label) {
  1203                 log.error(tree.pos(), "label.already.in.use",
  1204                           tree.label);
  1205                 break;
  1207             env1 = env1.next;
  1210         attribStat(tree.body, env.dup(tree));
  1211         result = null;
  1214     public void visitSwitch(JCSwitch tree) {
  1215         Type seltype = attribExpr(tree.selector, env);
  1217         Env<AttrContext> switchEnv =
  1218             env.dup(tree, env.info.dup(env.info.scope.dup()));
  1220         try {
  1222             boolean enumSwitch =
  1223                 allowEnums &&
  1224                 (seltype.tsym.flags() & Flags.ENUM) != 0;
  1225             boolean stringSwitch = false;
  1226             if (types.isSameType(seltype, syms.stringType)) {
  1227                 if (allowStringsInSwitch) {
  1228                     stringSwitch = true;
  1229                 } else {
  1230                     log.error(tree.selector.pos(), "string.switch.not.supported.in.source", sourceName);
  1233             if (!enumSwitch && !stringSwitch)
  1234                 seltype = chk.checkType(tree.selector.pos(), seltype, syms.intType);
  1236             // Attribute all cases and
  1237             // check that there are no duplicate case labels or default clauses.
  1238             Set<Object> labels = new HashSet<Object>(); // The set of case labels.
  1239             boolean hasDefault = false;      // Is there a default label?
  1240             for (List<JCCase> l = tree.cases; l.nonEmpty(); l = l.tail) {
  1241                 JCCase c = l.head;
  1242                 Env<AttrContext> caseEnv =
  1243                     switchEnv.dup(c, env.info.dup(switchEnv.info.scope.dup()));
  1244                 try {
  1245                     if (c.pat != null) {
  1246                         if (enumSwitch) {
  1247                             Symbol sym = enumConstant(c.pat, seltype);
  1248                             if (sym == null) {
  1249                                 log.error(c.pat.pos(), "enum.label.must.be.unqualified.enum");
  1250                             } else if (!labels.add(sym)) {
  1251                                 log.error(c.pos(), "duplicate.case.label");
  1253                         } else {
  1254                             Type pattype = attribExpr(c.pat, switchEnv, seltype);
  1255                             if (!pattype.hasTag(ERROR)) {
  1256                                 if (pattype.constValue() == null) {
  1257                                     log.error(c.pat.pos(),
  1258                                               (stringSwitch ? "string.const.req" : "const.expr.req"));
  1259                                 } else if (labels.contains(pattype.constValue())) {
  1260                                     log.error(c.pos(), "duplicate.case.label");
  1261                                 } else {
  1262                                     labels.add(pattype.constValue());
  1266                     } else if (hasDefault) {
  1267                         log.error(c.pos(), "duplicate.default.label");
  1268                     } else {
  1269                         hasDefault = true;
  1271                     attribStats(c.stats, caseEnv);
  1272                 } finally {
  1273                     caseEnv.info.scope.leave();
  1274                     addVars(c.stats, switchEnv.info.scope);
  1278             result = null;
  1280         finally {
  1281             switchEnv.info.scope.leave();
  1284     // where
  1285         /** Add any variables defined in stats to the switch scope. */
  1286         private static void addVars(List<JCStatement> stats, Scope switchScope) {
  1287             for (;stats.nonEmpty(); stats = stats.tail) {
  1288                 JCTree stat = stats.head;
  1289                 if (stat.hasTag(VARDEF))
  1290                     switchScope.enter(((JCVariableDecl) stat).sym);
  1293     // where
  1294     /** Return the selected enumeration constant symbol, or null. */
  1295     private Symbol enumConstant(JCTree tree, Type enumType) {
  1296         if (!tree.hasTag(IDENT)) {
  1297             log.error(tree.pos(), "enum.label.must.be.unqualified.enum");
  1298             return syms.errSymbol;
  1300         JCIdent ident = (JCIdent)tree;
  1301         Name name = ident.name;
  1302         for (Scope.Entry e = enumType.tsym.members().lookup(name);
  1303              e.scope != null; e = e.next()) {
  1304             if (e.sym.kind == VAR) {
  1305                 Symbol s = ident.sym = e.sym;
  1306                 ((VarSymbol)s).getConstValue(); // ensure initializer is evaluated
  1307                 ident.type = s.type;
  1308                 return ((s.flags_field & Flags.ENUM) == 0)
  1309                     ? null : s;
  1312         return null;
  1315     public void visitSynchronized(JCSynchronized tree) {
  1316         chk.checkRefType(tree.pos(), attribExpr(tree.lock, env));
  1317         attribStat(tree.body, env);
  1318         result = null;
  1321     public void visitTry(JCTry tree) {
  1322         // Create a new local environment with a local
  1323         Env<AttrContext> localEnv = env.dup(tree, env.info.dup(env.info.scope.dup()));
  1324         try {
  1325             boolean isTryWithResource = tree.resources.nonEmpty();
  1326             // Create a nested environment for attributing the try block if needed
  1327             Env<AttrContext> tryEnv = isTryWithResource ?
  1328                 env.dup(tree, localEnv.info.dup(localEnv.info.scope.dup())) :
  1329                 localEnv;
  1330             try {
  1331                 // Attribute resource declarations
  1332                 for (JCTree resource : tree.resources) {
  1333                     CheckContext twrContext = new Check.NestedCheckContext(resultInfo.checkContext) {
  1334                         @Override
  1335                         public void report(DiagnosticPosition pos, JCDiagnostic details) {
  1336                             chk.basicHandler.report(pos, diags.fragment("try.not.applicable.to.type", details));
  1338                     };
  1339                     ResultInfo twrResult = new ResultInfo(VAL, syms.autoCloseableType, twrContext);
  1340                     if (resource.hasTag(VARDEF)) {
  1341                         attribStat(resource, tryEnv);
  1342                         twrResult.check(resource, resource.type);
  1344                         //check that resource type cannot throw InterruptedException
  1345                         checkAutoCloseable(resource.pos(), localEnv, resource.type);
  1347                         VarSymbol var = ((JCVariableDecl) resource).sym;
  1348                         var.setData(ElementKind.RESOURCE_VARIABLE);
  1349                     } else {
  1350                         attribTree(resource, tryEnv, twrResult);
  1353                 // Attribute body
  1354                 attribStat(tree.body, tryEnv);
  1355             } finally {
  1356                 if (isTryWithResource)
  1357                     tryEnv.info.scope.leave();
  1360             // Attribute catch clauses
  1361             for (List<JCCatch> l = tree.catchers; l.nonEmpty(); l = l.tail) {
  1362                 JCCatch c = l.head;
  1363                 Env<AttrContext> catchEnv =
  1364                     localEnv.dup(c, localEnv.info.dup(localEnv.info.scope.dup()));
  1365                 try {
  1366                     Type ctype = attribStat(c.param, catchEnv);
  1367                     if (TreeInfo.isMultiCatch(c)) {
  1368                         //multi-catch parameter is implicitly marked as final
  1369                         c.param.sym.flags_field |= FINAL | UNION;
  1371                     if (c.param.sym.kind == Kinds.VAR) {
  1372                         c.param.sym.setData(ElementKind.EXCEPTION_PARAMETER);
  1374                     chk.checkType(c.param.vartype.pos(),
  1375                                   chk.checkClassType(c.param.vartype.pos(), ctype),
  1376                                   syms.throwableType);
  1377                     attribStat(c.body, catchEnv);
  1378                 } finally {
  1379                     catchEnv.info.scope.leave();
  1383             // Attribute finalizer
  1384             if (tree.finalizer != null) attribStat(tree.finalizer, localEnv);
  1385             result = null;
  1387         finally {
  1388             localEnv.info.scope.leave();
  1392     void checkAutoCloseable(DiagnosticPosition pos, Env<AttrContext> env, Type resource) {
  1393         if (!resource.isErroneous() &&
  1394             types.asSuper(resource, syms.autoCloseableType.tsym) != null &&
  1395             !types.isSameType(resource, syms.autoCloseableType)) { // Don't emit warning for AutoCloseable itself
  1396             Symbol close = syms.noSymbol;
  1397             Log.DiagnosticHandler discardHandler = new Log.DiscardDiagnosticHandler(log);
  1398             try {
  1399                 close = rs.resolveQualifiedMethod(pos,
  1400                         env,
  1401                         resource,
  1402                         names.close,
  1403                         List.<Type>nil(),
  1404                         List.<Type>nil());
  1406             finally {
  1407                 log.popDiagnosticHandler(discardHandler);
  1409             if (close.kind == MTH &&
  1410                     close.overrides(syms.autoCloseableClose, resource.tsym, types, true) &&
  1411                     chk.isHandled(syms.interruptedExceptionType, types.memberType(resource, close).getThrownTypes()) &&
  1412                     env.info.lint.isEnabled(LintCategory.TRY)) {
  1413                 log.warning(LintCategory.TRY, pos, "try.resource.throws.interrupted.exc", resource);
  1418     public void visitConditional(JCConditional tree) {
  1419         Type condtype = attribExpr(tree.cond, env, syms.booleanType);
  1421         tree.polyKind = (!allowPoly ||
  1422                 pt().hasTag(NONE) && pt() != Type.recoveryType ||
  1423                 isBooleanOrNumeric(env, tree)) ?
  1424                 PolyKind.STANDALONE : PolyKind.POLY;
  1426         if (tree.polyKind == PolyKind.POLY && resultInfo.pt.hasTag(VOID)) {
  1427             //cannot get here (i.e. it means we are returning from void method - which is already an error)
  1428             resultInfo.checkContext.report(tree, diags.fragment("conditional.target.cant.be.void"));
  1429             result = tree.type = types.createErrorType(resultInfo.pt);
  1430             return;
  1433         ResultInfo condInfo = tree.polyKind == PolyKind.STANDALONE ?
  1434                 unknownExprInfo :
  1435                 resultInfo.dup(new Check.NestedCheckContext(resultInfo.checkContext) {
  1436                     //this will use enclosing check context to check compatibility of
  1437                     //subexpression against target type; if we are in a method check context,
  1438                     //depending on whether boxing is allowed, we could have incompatibilities
  1439                     @Override
  1440                     public void report(DiagnosticPosition pos, JCDiagnostic details) {
  1441                         enclosingContext.report(pos, diags.fragment("incompatible.type.in.conditional", details));
  1443                 });
  1445         Type truetype = attribTree(tree.truepart, env, condInfo);
  1446         Type falsetype = attribTree(tree.falsepart, env, condInfo);
  1448         Type owntype = (tree.polyKind == PolyKind.STANDALONE) ? condType(tree, truetype, falsetype) : pt();
  1449         if (condtype.constValue() != null &&
  1450                 truetype.constValue() != null &&
  1451                 falsetype.constValue() != null &&
  1452                 !owntype.hasTag(NONE)) {
  1453             //constant folding
  1454             owntype = cfolder.coerce(condtype.isTrue() ? truetype : falsetype, owntype);
  1456         result = check(tree, owntype, VAL, resultInfo);
  1458     //where
  1459         private boolean isBooleanOrNumeric(Env<AttrContext> env, JCExpression tree) {
  1460             switch (tree.getTag()) {
  1461                 case LITERAL: return ((JCLiteral)tree).typetag.isSubRangeOf(DOUBLE) ||
  1462                               ((JCLiteral)tree).typetag == BOOLEAN ||
  1463                               ((JCLiteral)tree).typetag == BOT;
  1464                 case LAMBDA: case REFERENCE: return false;
  1465                 case PARENS: return isBooleanOrNumeric(env, ((JCParens)tree).expr);
  1466                 case CONDEXPR:
  1467                     JCConditional condTree = (JCConditional)tree;
  1468                     return isBooleanOrNumeric(env, condTree.truepart) &&
  1469                             isBooleanOrNumeric(env, condTree.falsepart);
  1470                 case APPLY:
  1471                     JCMethodInvocation speculativeMethodTree =
  1472                             (JCMethodInvocation)deferredAttr.attribSpeculative(tree, env, unknownExprInfo);
  1473                     Type owntype = TreeInfo.symbol(speculativeMethodTree.meth).type.getReturnType();
  1474                     return types.unboxedTypeOrType(owntype).isPrimitive();
  1475                 case NEWCLASS:
  1476                     JCExpression className =
  1477                             removeClassParams.translate(((JCNewClass)tree).clazz);
  1478                     JCExpression speculativeNewClassTree =
  1479                             (JCExpression)deferredAttr.attribSpeculative(className, env, unknownTypeInfo);
  1480                     return types.unboxedTypeOrType(speculativeNewClassTree.type).isPrimitive();
  1481                 default:
  1482                     Type speculativeType = deferredAttr.attribSpeculative(tree, env, unknownExprInfo).type;
  1483                     speculativeType = types.unboxedTypeOrType(speculativeType);
  1484                     return speculativeType.isPrimitive();
  1487         //where
  1488             TreeTranslator removeClassParams = new TreeTranslator() {
  1489                 @Override
  1490                 public void visitTypeApply(JCTypeApply tree) {
  1491                     result = translate(tree.clazz);
  1493             };
  1495         /** Compute the type of a conditional expression, after
  1496          *  checking that it exists.  See JLS 15.25. Does not take into
  1497          *  account the special case where condition and both arms
  1498          *  are constants.
  1500          *  @param pos      The source position to be used for error
  1501          *                  diagnostics.
  1502          *  @param thentype The type of the expression's then-part.
  1503          *  @param elsetype The type of the expression's else-part.
  1504          */
  1505         private Type condType(DiagnosticPosition pos,
  1506                                Type thentype, Type elsetype) {
  1507             // If same type, that is the result
  1508             if (types.isSameType(thentype, elsetype))
  1509                 return thentype.baseType();
  1511             Type thenUnboxed = (!allowBoxing || thentype.isPrimitive())
  1512                 ? thentype : types.unboxedType(thentype);
  1513             Type elseUnboxed = (!allowBoxing || elsetype.isPrimitive())
  1514                 ? elsetype : types.unboxedType(elsetype);
  1516             // Otherwise, if both arms can be converted to a numeric
  1517             // type, return the least numeric type that fits both arms
  1518             // (i.e. return larger of the two, or return int if one
  1519             // arm is short, the other is char).
  1520             if (thenUnboxed.isPrimitive() && elseUnboxed.isPrimitive()) {
  1521                 // If one arm has an integer subrange type (i.e., byte,
  1522                 // short, or char), and the other is an integer constant
  1523                 // that fits into the subrange, return the subrange type.
  1524                 if (thenUnboxed.getTag().isStrictSubRangeOf(INT) &&
  1525                     elseUnboxed.hasTag(INT) &&
  1526                     types.isAssignable(elseUnboxed, thenUnboxed)) {
  1527                     return thenUnboxed.baseType();
  1529                 if (elseUnboxed.getTag().isStrictSubRangeOf(INT) &&
  1530                     thenUnboxed.hasTag(INT) &&
  1531                     types.isAssignable(thenUnboxed, elseUnboxed)) {
  1532                     return elseUnboxed.baseType();
  1535                 for (TypeTag tag : primitiveTags) {
  1536                     Type candidate = syms.typeOfTag[tag.ordinal()];
  1537                     if (types.isSubtype(thenUnboxed, candidate) &&
  1538                         types.isSubtype(elseUnboxed, candidate)) {
  1539                         return candidate;
  1544             // Those were all the cases that could result in a primitive
  1545             if (allowBoxing) {
  1546                 if (thentype.isPrimitive())
  1547                     thentype = types.boxedClass(thentype).type;
  1548                 if (elsetype.isPrimitive())
  1549                     elsetype = types.boxedClass(elsetype).type;
  1552             if (types.isSubtype(thentype, elsetype))
  1553                 return elsetype.baseType();
  1554             if (types.isSubtype(elsetype, thentype))
  1555                 return thentype.baseType();
  1557             if (!allowBoxing || thentype.hasTag(VOID) || elsetype.hasTag(VOID)) {
  1558                 log.error(pos, "neither.conditional.subtype",
  1559                           thentype, elsetype);
  1560                 return thentype.baseType();
  1563             // both are known to be reference types.  The result is
  1564             // lub(thentype,elsetype). This cannot fail, as it will
  1565             // always be possible to infer "Object" if nothing better.
  1566             return types.lub(thentype.baseType(), elsetype.baseType());
  1569     final static TypeTag[] primitiveTags = new TypeTag[]{
  1570         BYTE,
  1571         CHAR,
  1572         SHORT,
  1573         INT,
  1574         LONG,
  1575         FLOAT,
  1576         DOUBLE,
  1577         BOOLEAN,
  1578     };
  1580     public void visitIf(JCIf tree) {
  1581         attribExpr(tree.cond, env, syms.booleanType);
  1582         attribStat(tree.thenpart, env);
  1583         if (tree.elsepart != null)
  1584             attribStat(tree.elsepart, env);
  1585         chk.checkEmptyIf(tree);
  1586         result = null;
  1589     public void visitExec(JCExpressionStatement tree) {
  1590         //a fresh environment is required for 292 inference to work properly ---
  1591         //see Infer.instantiatePolymorphicSignatureInstance()
  1592         Env<AttrContext> localEnv = env.dup(tree);
  1593         attribExpr(tree.expr, localEnv);
  1594         result = null;
  1597     public void visitBreak(JCBreak tree) {
  1598         tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
  1599         result = null;
  1602     public void visitContinue(JCContinue tree) {
  1603         tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
  1604         result = null;
  1606     //where
  1607         /** Return the target of a break or continue statement, if it exists,
  1608          *  report an error if not.
  1609          *  Note: The target of a labelled break or continue is the
  1610          *  (non-labelled) statement tree referred to by the label,
  1611          *  not the tree representing the labelled statement itself.
  1613          *  @param pos     The position to be used for error diagnostics
  1614          *  @param tag     The tag of the jump statement. This is either
  1615          *                 Tree.BREAK or Tree.CONTINUE.
  1616          *  @param label   The label of the jump statement, or null if no
  1617          *                 label is given.
  1618          *  @param env     The environment current at the jump statement.
  1619          */
  1620         private JCTree findJumpTarget(DiagnosticPosition pos,
  1621                                     JCTree.Tag tag,
  1622                                     Name label,
  1623                                     Env<AttrContext> env) {
  1624             // Search environments outwards from the point of jump.
  1625             Env<AttrContext> env1 = env;
  1626             LOOP:
  1627             while (env1 != null) {
  1628                 switch (env1.tree.getTag()) {
  1629                     case LABELLED:
  1630                         JCLabeledStatement labelled = (JCLabeledStatement)env1.tree;
  1631                         if (label == labelled.label) {
  1632                             // If jump is a continue, check that target is a loop.
  1633                             if (tag == CONTINUE) {
  1634                                 if (!labelled.body.hasTag(DOLOOP) &&
  1635                                         !labelled.body.hasTag(WHILELOOP) &&
  1636                                         !labelled.body.hasTag(FORLOOP) &&
  1637                                         !labelled.body.hasTag(FOREACHLOOP))
  1638                                     log.error(pos, "not.loop.label", label);
  1639                                 // Found labelled statement target, now go inwards
  1640                                 // to next non-labelled tree.
  1641                                 return TreeInfo.referencedStatement(labelled);
  1642                             } else {
  1643                                 return labelled;
  1646                         break;
  1647                     case DOLOOP:
  1648                     case WHILELOOP:
  1649                     case FORLOOP:
  1650                     case FOREACHLOOP:
  1651                         if (label == null) return env1.tree;
  1652                         break;
  1653                     case SWITCH:
  1654                         if (label == null && tag == BREAK) return env1.tree;
  1655                         break;
  1656                     case LAMBDA:
  1657                     case METHODDEF:
  1658                     case CLASSDEF:
  1659                         break LOOP;
  1660                     default:
  1662                 env1 = env1.next;
  1664             if (label != null)
  1665                 log.error(pos, "undef.label", label);
  1666             else if (tag == CONTINUE)
  1667                 log.error(pos, "cont.outside.loop");
  1668             else
  1669                 log.error(pos, "break.outside.switch.loop");
  1670             return null;
  1673     public void visitReturn(JCReturn tree) {
  1674         // Check that there is an enclosing method which is
  1675         // nested within than the enclosing class.
  1676         if (env.info.returnResult == null) {
  1677             log.error(tree.pos(), "ret.outside.meth");
  1678         } else {
  1679             // Attribute return expression, if it exists, and check that
  1680             // it conforms to result type of enclosing method.
  1681             if (tree.expr != null) {
  1682                 if (env.info.returnResult.pt.hasTag(VOID)) {
  1683                     env.info.returnResult.checkContext.report(tree.expr.pos(),
  1684                               diags.fragment("unexpected.ret.val"));
  1686                 attribTree(tree.expr, env, env.info.returnResult);
  1687             } else if (!env.info.returnResult.pt.hasTag(VOID) &&
  1688                     !env.info.returnResult.pt.hasTag(NONE)) {
  1689                 env.info.returnResult.checkContext.report(tree.pos(),
  1690                               diags.fragment("missing.ret.val"));
  1693         result = null;
  1696     public void visitThrow(JCThrow tree) {
  1697         Type owntype = attribExpr(tree.expr, env, allowPoly ? Type.noType : syms.throwableType);
  1698         if (allowPoly) {
  1699             chk.checkType(tree, owntype, syms.throwableType);
  1701         result = null;
  1704     public void visitAssert(JCAssert tree) {
  1705         attribExpr(tree.cond, env, syms.booleanType);
  1706         if (tree.detail != null) {
  1707             chk.checkNonVoid(tree.detail.pos(), attribExpr(tree.detail, env));
  1709         result = null;
  1712      /** Visitor method for method invocations.
  1713      *  NOTE: The method part of an application will have in its type field
  1714      *        the return type of the method, not the method's type itself!
  1715      */
  1716     public void visitApply(JCMethodInvocation tree) {
  1717         // The local environment of a method application is
  1718         // a new environment nested in the current one.
  1719         Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
  1721         // The types of the actual method arguments.
  1722         List<Type> argtypes;
  1724         // The types of the actual method type arguments.
  1725         List<Type> typeargtypes = null;
  1727         Name methName = TreeInfo.name(tree.meth);
  1729         boolean isConstructorCall =
  1730             methName == names._this || methName == names._super;
  1732         ListBuffer<Type> argtypesBuf = new ListBuffer<>();
  1733         if (isConstructorCall) {
  1734             // We are seeing a ...this(...) or ...super(...) call.
  1735             // Check that this is the first statement in a constructor.
  1736             if (checkFirstConstructorStat(tree, env)) {
  1738                 // Record the fact
  1739                 // that this is a constructor call (using isSelfCall).
  1740                 localEnv.info.isSelfCall = true;
  1742                 // Attribute arguments, yielding list of argument types.
  1743                 int kind = attribArgs(MTH, tree.args, localEnv, argtypesBuf);
  1744                 argtypes = argtypesBuf.toList();
  1745                 typeargtypes = attribTypes(tree.typeargs, localEnv);
  1747                 // Variable `site' points to the class in which the called
  1748                 // constructor is defined.
  1749                 Type site = env.enclClass.sym.type;
  1750                 if (methName == names._super) {
  1751                     if (site == syms.objectType) {
  1752                         log.error(tree.meth.pos(), "no.superclass", site);
  1753                         site = types.createErrorType(syms.objectType);
  1754                     } else {
  1755                         site = types.supertype(site);
  1759                 if (site.hasTag(CLASS)) {
  1760                     Type encl = site.getEnclosingType();
  1761                     while (encl != null && encl.hasTag(TYPEVAR))
  1762                         encl = encl.getUpperBound();
  1763                     if (encl.hasTag(CLASS)) {
  1764                         // we are calling a nested class
  1766                         if (tree.meth.hasTag(SELECT)) {
  1767                             JCTree qualifier = ((JCFieldAccess) tree.meth).selected;
  1769                             // We are seeing a prefixed call, of the form
  1770                             //     <expr>.super(...).
  1771                             // Check that the prefix expression conforms
  1772                             // to the outer instance type of the class.
  1773                             chk.checkRefType(qualifier.pos(),
  1774                                              attribExpr(qualifier, localEnv,
  1775                                                         encl));
  1776                         } else if (methName == names._super) {
  1777                             // qualifier omitted; check for existence
  1778                             // of an appropriate implicit qualifier.
  1779                             rs.resolveImplicitThis(tree.meth.pos(),
  1780                                                    localEnv, site, true);
  1782                     } else if (tree.meth.hasTag(SELECT)) {
  1783                         log.error(tree.meth.pos(), "illegal.qual.not.icls",
  1784                                   site.tsym);
  1787                     // if we're calling a java.lang.Enum constructor,
  1788                     // prefix the implicit String and int parameters
  1789                     if (site.tsym == syms.enumSym && allowEnums)
  1790                         argtypes = argtypes.prepend(syms.intType).prepend(syms.stringType);
  1792                     // Resolve the called constructor under the assumption
  1793                     // that we are referring to a superclass instance of the
  1794                     // current instance (JLS ???).
  1795                     boolean selectSuperPrev = localEnv.info.selectSuper;
  1796                     localEnv.info.selectSuper = true;
  1797                     localEnv.info.pendingResolutionPhase = null;
  1798                     Symbol sym = rs.resolveConstructor(
  1799                         tree.meth.pos(), localEnv, site, argtypes, typeargtypes);
  1800                     localEnv.info.selectSuper = selectSuperPrev;
  1802                     // Set method symbol to resolved constructor...
  1803                     TreeInfo.setSymbol(tree.meth, sym);
  1805                     // ...and check that it is legal in the current context.
  1806                     // (this will also set the tree's type)
  1807                     Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes);
  1808                     checkId(tree.meth, site, sym, localEnv, new ResultInfo(kind, mpt));
  1810                 // Otherwise, `site' is an error type and we do nothing
  1812             result = tree.type = syms.voidType;
  1813         } else {
  1814             // Otherwise, we are seeing a regular method call.
  1815             // Attribute the arguments, yielding list of argument types, ...
  1816             int kind = attribArgs(VAL, tree.args, localEnv, argtypesBuf);
  1817             argtypes = argtypesBuf.toList();
  1818             typeargtypes = attribAnyTypes(tree.typeargs, localEnv);
  1820             // ... and attribute the method using as a prototype a methodtype
  1821             // whose formal argument types is exactly the list of actual
  1822             // arguments (this will also set the method symbol).
  1823             Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes);
  1824             localEnv.info.pendingResolutionPhase = null;
  1825             Type mtype = attribTree(tree.meth, localEnv, new ResultInfo(kind, mpt, resultInfo.checkContext));
  1827             // Compute the result type.
  1828             Type restype = mtype.getReturnType();
  1829             if (restype.hasTag(WILDCARD))
  1830                 throw new AssertionError(mtype);
  1832             Type qualifier = (tree.meth.hasTag(SELECT))
  1833                     ? ((JCFieldAccess) tree.meth).selected.type
  1834                     : env.enclClass.sym.type;
  1835             restype = adjustMethodReturnType(qualifier, methName, argtypes, restype);
  1837             chk.checkRefTypes(tree.typeargs, typeargtypes);
  1839             // Check that value of resulting type is admissible in the
  1840             // current context.  Also, capture the return type
  1841             result = check(tree, capture(restype), VAL, resultInfo);
  1843         chk.validate(tree.typeargs, localEnv);
  1845     //where
  1846         Type adjustMethodReturnType(Type qualifierType, Name methodName, List<Type> argtypes, Type restype) {
  1847             if (allowCovariantReturns &&
  1848                     methodName == names.clone &&
  1849                 types.isArray(qualifierType)) {
  1850                 // as a special case, array.clone() has a result that is
  1851                 // the same as static type of the array being cloned
  1852                 return qualifierType;
  1853             } else if (allowGenerics &&
  1854                     methodName == names.getClass &&
  1855                     argtypes.isEmpty()) {
  1856                 // as a special case, x.getClass() has type Class<? extends |X|>
  1857                 return new ClassType(restype.getEnclosingType(),
  1858                               List.<Type>of(new WildcardType(types.erasure(qualifierType),
  1859                                                                BoundKind.EXTENDS,
  1860                                                                syms.boundClass)),
  1861                               restype.tsym);
  1862             } else {
  1863                 return restype;
  1867         /** Check that given application node appears as first statement
  1868          *  in a constructor call.
  1869          *  @param tree   The application node
  1870          *  @param env    The environment current at the application.
  1871          */
  1872         boolean checkFirstConstructorStat(JCMethodInvocation tree, Env<AttrContext> env) {
  1873             JCMethodDecl enclMethod = env.enclMethod;
  1874             if (enclMethod != null && enclMethod.name == names.init) {
  1875                 JCBlock body = enclMethod.body;
  1876                 if (body.stats.head.hasTag(EXEC) &&
  1877                     ((JCExpressionStatement) body.stats.head).expr == tree)
  1878                     return true;
  1880             log.error(tree.pos(),"call.must.be.first.stmt.in.ctor",
  1881                       TreeInfo.name(tree.meth));
  1882             return false;
  1885         /** Obtain a method type with given argument types.
  1886          */
  1887         Type newMethodTemplate(Type restype, List<Type> argtypes, List<Type> typeargtypes) {
  1888             MethodType mt = new MethodType(argtypes, restype, List.<Type>nil(), syms.methodClass);
  1889             return (typeargtypes == null) ? mt : (Type)new ForAll(typeargtypes, mt);
  1892     public void visitNewClass(final JCNewClass tree) {
  1893         Type owntype = types.createErrorType(tree.type);
  1895         // The local environment of a class creation is
  1896         // a new environment nested in the current one.
  1897         Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
  1899         // The anonymous inner class definition of the new expression,
  1900         // if one is defined by it.
  1901         JCClassDecl cdef = tree.def;
  1903         // If enclosing class is given, attribute it, and
  1904         // complete class name to be fully qualified
  1905         JCExpression clazz = tree.clazz; // Class field following new
  1906         JCExpression clazzid;            // Identifier in class field
  1907         JCAnnotatedType annoclazzid;     // Annotated type enclosing clazzid
  1908         annoclazzid = null;
  1910         if (clazz.hasTag(TYPEAPPLY)) {
  1911             clazzid = ((JCTypeApply) clazz).clazz;
  1912             if (clazzid.hasTag(ANNOTATED_TYPE)) {
  1913                 annoclazzid = (JCAnnotatedType) clazzid;
  1914                 clazzid = annoclazzid.underlyingType;
  1916         } else {
  1917             if (clazz.hasTag(ANNOTATED_TYPE)) {
  1918                 annoclazzid = (JCAnnotatedType) clazz;
  1919                 clazzid = annoclazzid.underlyingType;
  1920             } else {
  1921                 clazzid = clazz;
  1925         JCExpression clazzid1 = clazzid; // The same in fully qualified form
  1927         if (tree.encl != null) {
  1928             // We are seeing a qualified new, of the form
  1929             //    <expr>.new C <...> (...) ...
  1930             // In this case, we let clazz stand for the name of the
  1931             // allocated class C prefixed with the type of the qualifier
  1932             // expression, so that we can
  1933             // resolve it with standard techniques later. I.e., if
  1934             // <expr> has type T, then <expr>.new C <...> (...)
  1935             // yields a clazz T.C.
  1936             Type encltype = chk.checkRefType(tree.encl.pos(),
  1937                                              attribExpr(tree.encl, env));
  1938             // TODO 308: in <expr>.new C, do we also want to add the type annotations
  1939             // from expr to the combined type, or not? Yes, do this.
  1940             clazzid1 = make.at(clazz.pos).Select(make.Type(encltype),
  1941                                                  ((JCIdent) clazzid).name);
  1943             EndPosTable endPosTable = this.env.toplevel.endPositions;
  1944             endPosTable.storeEnd(clazzid1, tree.getEndPosition(endPosTable));
  1945             if (clazz.hasTag(ANNOTATED_TYPE)) {
  1946                 JCAnnotatedType annoType = (JCAnnotatedType) clazz;
  1947                 List<JCAnnotation> annos = annoType.annotations;
  1949                 if (annoType.underlyingType.hasTag(TYPEAPPLY)) {
  1950                     clazzid1 = make.at(tree.pos).
  1951                         TypeApply(clazzid1,
  1952                                   ((JCTypeApply) clazz).arguments);
  1955                 clazzid1 = make.at(tree.pos).
  1956                     AnnotatedType(annos, clazzid1);
  1957             } else if (clazz.hasTag(TYPEAPPLY)) {
  1958                 clazzid1 = make.at(tree.pos).
  1959                     TypeApply(clazzid1,
  1960                               ((JCTypeApply) clazz).arguments);
  1963             clazz = clazzid1;
  1966         // Attribute clazz expression and store
  1967         // symbol + type back into the attributed tree.
  1968         Type clazztype = TreeInfo.isEnumInit(env.tree) ?
  1969             attribIdentAsEnumType(env, (JCIdent)clazz) :
  1970             attribType(clazz, env);
  1972         clazztype = chk.checkDiamond(tree, clazztype);
  1973         chk.validate(clazz, localEnv);
  1974         if (tree.encl != null) {
  1975             // We have to work in this case to store
  1976             // symbol + type back into the attributed tree.
  1977             tree.clazz.type = clazztype;
  1978             TreeInfo.setSymbol(clazzid, TreeInfo.symbol(clazzid1));
  1979             clazzid.type = ((JCIdent) clazzid).sym.type;
  1980             if (annoclazzid != null) {
  1981                 annoclazzid.type = clazzid.type;
  1983             if (!clazztype.isErroneous()) {
  1984                 if (cdef != null && clazztype.tsym.isInterface()) {
  1985                     log.error(tree.encl.pos(), "anon.class.impl.intf.no.qual.for.new");
  1986                 } else if (clazztype.tsym.isStatic()) {
  1987                     log.error(tree.encl.pos(), "qualified.new.of.static.class", clazztype.tsym);
  1990         } else if (!clazztype.tsym.isInterface() &&
  1991                    clazztype.getEnclosingType().hasTag(CLASS)) {
  1992             // Check for the existence of an apropos outer instance
  1993             rs.resolveImplicitThis(tree.pos(), env, clazztype);
  1996         // Attribute constructor arguments.
  1997         ListBuffer<Type> argtypesBuf = new ListBuffer<>();
  1998         int pkind = attribArgs(VAL, tree.args, localEnv, argtypesBuf);
  1999         List<Type> argtypes = argtypesBuf.toList();
  2000         List<Type> typeargtypes = attribTypes(tree.typeargs, localEnv);
  2002         // If we have made no mistakes in the class type...
  2003         if (clazztype.hasTag(CLASS)) {
  2004             // Enums may not be instantiated except implicitly
  2005             if (allowEnums &&
  2006                 (clazztype.tsym.flags_field&Flags.ENUM) != 0 &&
  2007                 (!env.tree.hasTag(VARDEF) ||
  2008                  (((JCVariableDecl) env.tree).mods.flags&Flags.ENUM) == 0 ||
  2009                  ((JCVariableDecl) env.tree).init != tree))
  2010                 log.error(tree.pos(), "enum.cant.be.instantiated");
  2011             // Check that class is not abstract
  2012             if (cdef == null &&
  2013                 (clazztype.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
  2014                 log.error(tree.pos(), "abstract.cant.be.instantiated",
  2015                           clazztype.tsym);
  2016             } else if (cdef != null && clazztype.tsym.isInterface()) {
  2017                 // Check that no constructor arguments are given to
  2018                 // anonymous classes implementing an interface
  2019                 if (!argtypes.isEmpty())
  2020                     log.error(tree.args.head.pos(), "anon.class.impl.intf.no.args");
  2022                 if (!typeargtypes.isEmpty())
  2023                     log.error(tree.typeargs.head.pos(), "anon.class.impl.intf.no.typeargs");
  2025                 // Error recovery: pretend no arguments were supplied.
  2026                 argtypes = List.nil();
  2027                 typeargtypes = List.nil();
  2028             } else if (TreeInfo.isDiamond(tree)) {
  2029                 ClassType site = new ClassType(clazztype.getEnclosingType(),
  2030                             clazztype.tsym.type.getTypeArguments(),
  2031                             clazztype.tsym);
  2033                 Env<AttrContext> diamondEnv = localEnv.dup(tree);
  2034                 diamondEnv.info.selectSuper = cdef != null;
  2035                 diamondEnv.info.pendingResolutionPhase = null;
  2037                 //if the type of the instance creation expression is a class type
  2038                 //apply method resolution inference (JLS 15.12.2.7). The return type
  2039                 //of the resolved constructor will be a partially instantiated type
  2040                 Symbol constructor = rs.resolveDiamond(tree.pos(),
  2041                             diamondEnv,
  2042                             site,
  2043                             argtypes,
  2044                             typeargtypes);
  2045                 tree.constructor = constructor.baseSymbol();
  2047                 final TypeSymbol csym = clazztype.tsym;
  2048                 ResultInfo diamondResult = new ResultInfo(pkind, newMethodTemplate(resultInfo.pt, argtypes, typeargtypes), new Check.NestedCheckContext(resultInfo.checkContext) {
  2049                     @Override
  2050                     public void report(DiagnosticPosition _unused, JCDiagnostic details) {
  2051                         enclosingContext.report(tree.clazz,
  2052                                 diags.fragment("cant.apply.diamond.1", diags.fragment("diamond", csym), details));
  2054                 });
  2055                 Type constructorType = tree.constructorType = types.createErrorType(clazztype);
  2056                 constructorType = checkId(noCheckTree, site,
  2057                         constructor,
  2058                         diamondEnv,
  2059                         diamondResult);
  2061                 tree.clazz.type = types.createErrorType(clazztype);
  2062                 if (!constructorType.isErroneous()) {
  2063                     tree.clazz.type = clazztype = constructorType.getReturnType();
  2064                     tree.constructorType = types.createMethodTypeWithReturn(constructorType, syms.voidType);
  2066                 clazztype = chk.checkClassType(tree.clazz, tree.clazz.type, true);
  2069             // Resolve the called constructor under the assumption
  2070             // that we are referring to a superclass instance of the
  2071             // current instance (JLS ???).
  2072             else {
  2073                 //the following code alters some of the fields in the current
  2074                 //AttrContext - hence, the current context must be dup'ed in
  2075                 //order to avoid downstream failures
  2076                 Env<AttrContext> rsEnv = localEnv.dup(tree);
  2077                 rsEnv.info.selectSuper = cdef != null;
  2078                 rsEnv.info.pendingResolutionPhase = null;
  2079                 tree.constructor = rs.resolveConstructor(
  2080                     tree.pos(), rsEnv, clazztype, argtypes, typeargtypes);
  2081                 if (cdef == null) { //do not check twice!
  2082                     tree.constructorType = checkId(noCheckTree,
  2083                             clazztype,
  2084                             tree.constructor,
  2085                             rsEnv,
  2086                             new ResultInfo(pkind, newMethodTemplate(syms.voidType, argtypes, typeargtypes)));
  2087                     if (rsEnv.info.lastResolveVarargs())
  2088                         Assert.check(tree.constructorType.isErroneous() || tree.varargsElement != null);
  2090                 if (cdef == null &&
  2091                         !clazztype.isErroneous() &&
  2092                         clazztype.getTypeArguments().nonEmpty() &&
  2093                         findDiamonds) {
  2094                     findDiamond(localEnv, tree, clazztype);
  2098             if (cdef != null) {
  2099                 // We are seeing an anonymous class instance creation.
  2100                 // In this case, the class instance creation
  2101                 // expression
  2102                 //
  2103                 //    E.new <typeargs1>C<typargs2>(args) { ... }
  2104                 //
  2105                 // is represented internally as
  2106                 //
  2107                 //    E . new <typeargs1>C<typargs2>(args) ( class <empty-name> { ... } )  .
  2108                 //
  2109                 // This expression is then *transformed* as follows:
  2110                 //
  2111                 // (1) add a STATIC flag to the class definition
  2112                 //     if the current environment is static
  2113                 // (2) add an extends or implements clause
  2114                 // (3) add a constructor.
  2115                 //
  2116                 // For instance, if C is a class, and ET is the type of E,
  2117                 // the expression
  2118                 //
  2119                 //    E.new <typeargs1>C<typargs2>(args) { ... }
  2120                 //
  2121                 // is translated to (where X is a fresh name and typarams is the
  2122                 // parameter list of the super constructor):
  2123                 //
  2124                 //   new <typeargs1>X(<*nullchk*>E, args) where
  2125                 //     X extends C<typargs2> {
  2126                 //       <typarams> X(ET e, args) {
  2127                 //         e.<typeargs1>super(args)
  2128                 //       }
  2129                 //       ...
  2130                 //     }
  2131                 if (Resolve.isStatic(env)) cdef.mods.flags |= STATIC;
  2133                 if (clazztype.tsym.isInterface()) {
  2134                     cdef.implementing = List.of(clazz);
  2135                 } else {
  2136                     cdef.extending = clazz;
  2139                 if (resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK &&
  2140                     isSerializable(clazztype)) {
  2141                     localEnv.info.isSerializable = true;
  2144                 attribStat(cdef, localEnv);
  2146                 checkLambdaCandidate(tree, cdef.sym, clazztype);
  2148                 // If an outer instance is given,
  2149                 // prefix it to the constructor arguments
  2150                 // and delete it from the new expression
  2151                 if (tree.encl != null && !clazztype.tsym.isInterface()) {
  2152                     tree.args = tree.args.prepend(makeNullCheck(tree.encl));
  2153                     argtypes = argtypes.prepend(tree.encl.type);
  2154                     tree.encl = null;
  2157                 // Reassign clazztype and recompute constructor.
  2158                 clazztype = cdef.sym.type;
  2159                 Symbol sym = tree.constructor = rs.resolveConstructor(
  2160                     tree.pos(), localEnv, clazztype, argtypes, typeargtypes);
  2161                 Assert.check(sym.kind < AMBIGUOUS);
  2162                 tree.constructor = sym;
  2163                 tree.constructorType = checkId(noCheckTree,
  2164                     clazztype,
  2165                     tree.constructor,
  2166                     localEnv,
  2167                     new ResultInfo(pkind, newMethodTemplate(syms.voidType, argtypes, typeargtypes)));
  2170             if (tree.constructor != null && tree.constructor.kind == MTH)
  2171                 owntype = clazztype;
  2173         result = check(tree, owntype, VAL, resultInfo);
  2174         InferenceContext inferenceContext = resultInfo.checkContext.inferenceContext();
  2175         if (tree.constructorType != null && inferenceContext.free(tree.constructorType)) {
  2176             //we need to wait for inference to finish and then replace inference vars in the constructor type
  2177             inferenceContext.addFreeTypeListener(List.of(tree.constructorType),
  2178                     new FreeTypeListener() {
  2179                         @Override
  2180                         public void typesInferred(InferenceContext instantiatedContext) {
  2181                             tree.constructorType = instantiatedContext.asInstType(tree.constructorType);
  2183                     });
  2185         chk.validate(tree.typeargs, localEnv);
  2187     //where
  2188         void findDiamond(Env<AttrContext> env, JCNewClass tree, Type clazztype) {
  2189             JCTypeApply ta = (JCTypeApply)tree.clazz;
  2190             List<JCExpression> prevTypeargs = ta.arguments;
  2191             try {
  2192                 //create a 'fake' diamond AST node by removing type-argument trees
  2193                 ta.arguments = List.nil();
  2194                 ResultInfo findDiamondResult = new ResultInfo(VAL,
  2195                         resultInfo.checkContext.inferenceContext().free(resultInfo.pt) ? Type.noType : pt());
  2196                 Type inferred = deferredAttr.attribSpeculative(tree, env, findDiamondResult).type;
  2197                 Type polyPt = allowPoly ?
  2198                         syms.objectType :
  2199                         clazztype;
  2200                 if (!inferred.isErroneous() &&
  2201                     (allowPoly && pt() == Infer.anyPoly ?
  2202                         types.isSameType(inferred, clazztype) :
  2203                         types.isAssignable(inferred, pt().hasTag(NONE) ? polyPt : pt(), types.noWarnings))) {
  2204                     String key = types.isSameType(clazztype, inferred) ?
  2205                         "diamond.redundant.args" :
  2206                         "diamond.redundant.args.1";
  2207                     log.warning(tree.clazz.pos(), key, clazztype, inferred);
  2209             } finally {
  2210                 ta.arguments = prevTypeargs;
  2214             private void checkLambdaCandidate(JCNewClass tree, ClassSymbol csym, Type clazztype) {
  2215                 if (allowLambda &&
  2216                         identifyLambdaCandidate &&
  2217                         clazztype.hasTag(CLASS) &&
  2218                         !pt().hasTag(NONE) &&
  2219                         types.isFunctionalInterface(clazztype.tsym)) {
  2220                     Symbol descriptor = types.findDescriptorSymbol(clazztype.tsym);
  2221                     int count = 0;
  2222                     boolean found = false;
  2223                     for (Symbol sym : csym.members().getElements()) {
  2224                         if ((sym.flags() & SYNTHETIC) != 0 ||
  2225                                 sym.isConstructor()) continue;
  2226                         count++;
  2227                         if (sym.kind != MTH ||
  2228                                 !sym.name.equals(descriptor.name)) continue;
  2229                         Type mtype = types.memberType(clazztype, sym);
  2230                         if (types.overrideEquivalent(mtype, types.memberType(clazztype, descriptor))) {
  2231                             found = true;
  2234                     if (found && count == 1) {
  2235                         log.note(tree.def, "potential.lambda.found");
  2240     /** Make an attributed null check tree.
  2241      */
  2242     public JCExpression makeNullCheck(JCExpression arg) {
  2243         // optimization: X.this is never null; skip null check
  2244         Name name = TreeInfo.name(arg);
  2245         if (name == names._this || name == names._super) return arg;
  2247         JCTree.Tag optag = NULLCHK;
  2248         JCUnary tree = make.at(arg.pos).Unary(optag, arg);
  2249         tree.operator = syms.nullcheck;
  2250         tree.type = arg.type;
  2251         return tree;
  2254     public void visitNewArray(JCNewArray tree) {
  2255         Type owntype = types.createErrorType(tree.type);
  2256         Env<AttrContext> localEnv = env.dup(tree);
  2257         Type elemtype;
  2258         if (tree.elemtype != null) {
  2259             elemtype = attribType(tree.elemtype, localEnv);
  2260             chk.validate(tree.elemtype, localEnv);
  2261             owntype = elemtype;
  2262             for (List<JCExpression> l = tree.dims; l.nonEmpty(); l = l.tail) {
  2263                 attribExpr(l.head, localEnv, syms.intType);
  2264                 owntype = new ArrayType(owntype, syms.arrayClass);
  2266         } else {
  2267             // we are seeing an untyped aggregate { ... }
  2268             // this is allowed only if the prototype is an array
  2269             if (pt().hasTag(ARRAY)) {
  2270                 elemtype = types.elemtype(pt());
  2271             } else {
  2272                 if (!pt().hasTag(ERROR)) {
  2273                     log.error(tree.pos(), "illegal.initializer.for.type",
  2274                               pt());
  2276                 elemtype = types.createErrorType(pt());
  2279         if (tree.elems != null) {
  2280             attribExprs(tree.elems, localEnv, elemtype);
  2281             owntype = new ArrayType(elemtype, syms.arrayClass);
  2283         if (!types.isReifiable(elemtype))
  2284             log.error(tree.pos(), "generic.array.creation");
  2285         result = check(tree, owntype, VAL, resultInfo);
  2288     /*
  2289      * A lambda expression can only be attributed when a target-type is available.
  2290      * In addition, if the target-type is that of a functional interface whose
  2291      * descriptor contains inference variables in argument position the lambda expression
  2292      * is 'stuck' (see DeferredAttr).
  2293      */
  2294     @Override
  2295     public void visitLambda(final JCLambda that) {
  2296         if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) {
  2297             if (pt().hasTag(NONE)) {
  2298                 //lambda only allowed in assignment or method invocation/cast context
  2299                 log.error(that.pos(), "unexpected.lambda");
  2301             result = that.type = types.createErrorType(pt());
  2302             return;
  2304         //create an environment for attribution of the lambda expression
  2305         final Env<AttrContext> localEnv = lambdaEnv(that, env);
  2306         boolean needsRecovery =
  2307                 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK;
  2308         try {
  2309             Type currentTarget = pt();
  2310             if (needsRecovery && isSerializable(currentTarget)) {
  2311                 localEnv.info.isSerializable = true;
  2313             List<Type> explicitParamTypes = null;
  2314             if (that.paramKind == JCLambda.ParameterKind.EXPLICIT) {
  2315                 //attribute lambda parameters
  2316                 attribStats(that.params, localEnv);
  2317                 explicitParamTypes = TreeInfo.types(that.params);
  2320             Type lambdaType;
  2321             if (pt() != Type.recoveryType) {
  2322                 /* We need to adjust the target. If the target is an
  2323                  * intersection type, for example: SAM & I1 & I2 ...
  2324                  * the target will be updated to SAM
  2325                  */
  2326                 currentTarget = targetChecker.visit(currentTarget, that);
  2327                 if (explicitParamTypes != null) {
  2328                     currentTarget = infer.instantiateFunctionalInterface(that,
  2329                             currentTarget, explicitParamTypes, resultInfo.checkContext);
  2331                 currentTarget = types.removeWildcards(currentTarget);
  2332                 lambdaType = types.findDescriptorType(currentTarget);
  2333             } else {
  2334                 currentTarget = Type.recoveryType;
  2335                 lambdaType = fallbackDescriptorType(that);
  2338             setFunctionalInfo(localEnv, that, pt(), lambdaType, currentTarget, resultInfo.checkContext);
  2340             if (lambdaType.hasTag(FORALL)) {
  2341                 //lambda expression target desc cannot be a generic method
  2342                 resultInfo.checkContext.report(that, diags.fragment("invalid.generic.lambda.target",
  2343                         lambdaType, kindName(currentTarget.tsym), currentTarget.tsym));
  2344                 result = that.type = types.createErrorType(pt());
  2345                 return;
  2348             if (that.paramKind == JCLambda.ParameterKind.IMPLICIT) {
  2349                 //add param type info in the AST
  2350                 List<Type> actuals = lambdaType.getParameterTypes();
  2351                 List<JCVariableDecl> params = that.params;
  2353                 boolean arityMismatch = false;
  2355                 while (params.nonEmpty()) {
  2356                     if (actuals.isEmpty()) {
  2357                         //not enough actuals to perform lambda parameter inference
  2358                         arityMismatch = true;
  2360                     //reset previously set info
  2361                     Type argType = arityMismatch ?
  2362                             syms.errType :
  2363                             actuals.head;
  2364                     params.head.vartype = make.at(params.head).Type(argType);
  2365                     params.head.sym = null;
  2366                     actuals = actuals.isEmpty() ?
  2367                             actuals :
  2368                             actuals.tail;
  2369                     params = params.tail;
  2372                 //attribute lambda parameters
  2373                 attribStats(that.params, localEnv);
  2375                 if (arityMismatch) {
  2376                     resultInfo.checkContext.report(that, diags.fragment("incompatible.arg.types.in.lambda"));
  2377                         result = that.type = types.createErrorType(currentTarget);
  2378                         return;
  2382             //from this point on, no recovery is needed; if we are in assignment context
  2383             //we will be able to attribute the whole lambda body, regardless of errors;
  2384             //if we are in a 'check' method context, and the lambda is not compatible
  2385             //with the target-type, it will be recovered anyway in Attr.checkId
  2386             needsRecovery = false;
  2388             FunctionalReturnContext funcContext = that.getBodyKind() == JCLambda.BodyKind.EXPRESSION ?
  2389                     new ExpressionLambdaReturnContext((JCExpression)that.getBody(), resultInfo.checkContext) :
  2390                     new FunctionalReturnContext(resultInfo.checkContext);
  2392             ResultInfo bodyResultInfo = lambdaType.getReturnType() == Type.recoveryType ?
  2393                 recoveryInfo :
  2394                 new ResultInfo(VAL, lambdaType.getReturnType(), funcContext);
  2395             localEnv.info.returnResult = bodyResultInfo;
  2397             if (that.getBodyKind() == JCLambda.BodyKind.EXPRESSION) {
  2398                 attribTree(that.getBody(), localEnv, bodyResultInfo);
  2399             } else {
  2400                 JCBlock body = (JCBlock)that.body;
  2401                 attribStats(body.stats, localEnv);
  2404             result = check(that, currentTarget, VAL, resultInfo);
  2406             boolean isSpeculativeRound =
  2407                     resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE;
  2409             preFlow(that);
  2410             flow.analyzeLambda(env, that, make, isSpeculativeRound);
  2412             that.type = currentTarget; //avoids recovery at this stage
  2413             checkLambdaCompatible(that, lambdaType, resultInfo.checkContext);
  2415             if (!isSpeculativeRound) {
  2416                 //add thrown types as bounds to the thrown types free variables if needed:
  2417                 if (resultInfo.checkContext.inferenceContext().free(lambdaType.getThrownTypes())) {
  2418                     List<Type> inferredThrownTypes = flow.analyzeLambdaThrownTypes(env, that, make);
  2419                     List<Type> thrownTypes = resultInfo.checkContext.inferenceContext().asUndetVars(lambdaType.getThrownTypes());
  2421                     chk.unhandled(inferredThrownTypes, thrownTypes);
  2424                 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), lambdaType, currentTarget);
  2426             result = check(that, currentTarget, VAL, resultInfo);
  2427         } catch (Types.FunctionDescriptorLookupError ex) {
  2428             JCDiagnostic cause = ex.getDiagnostic();
  2429             resultInfo.checkContext.report(that, cause);
  2430             result = that.type = types.createErrorType(pt());
  2431             return;
  2432         } finally {
  2433             localEnv.info.scope.leave();
  2434             if (needsRecovery) {
  2435                 attribTree(that, env, recoveryInfo);
  2439     //where
  2440         void preFlow(JCLambda tree) {
  2441             new PostAttrAnalyzer() {
  2442                 @Override
  2443                 public void scan(JCTree tree) {
  2444                     if (tree == null ||
  2445                             (tree.type != null &&
  2446                             tree.type == Type.stuckType)) {
  2447                         //don't touch stuck expressions!
  2448                         return;
  2450                     super.scan(tree);
  2452             }.scan(tree);
  2455         Types.MapVisitor<DiagnosticPosition> targetChecker = new Types.MapVisitor<DiagnosticPosition>() {
  2457             @Override
  2458             public Type visitClassType(ClassType t, DiagnosticPosition pos) {
  2459                 return t.isIntersection() ?
  2460                         visitIntersectionClassType((IntersectionClassType)t, pos) : t;
  2463             public Type visitIntersectionClassType(IntersectionClassType ict, DiagnosticPosition pos) {
  2464                 Symbol desc = types.findDescriptorSymbol(makeNotionalInterface(ict));
  2465                 Type target = null;
  2466                 for (Type bound : ict.getExplicitComponents()) {
  2467                     TypeSymbol boundSym = bound.tsym;
  2468                     if (types.isFunctionalInterface(boundSym) &&
  2469                             types.findDescriptorSymbol(boundSym) == desc) {
  2470                         target = bound;
  2471                     } else if (!boundSym.isInterface() || (boundSym.flags() & ANNOTATION) != 0) {
  2472                         //bound must be an interface
  2473                         reportIntersectionError(pos, "not.an.intf.component", boundSym);
  2476                 return target != null ?
  2477                         target :
  2478                         ict.getExplicitComponents().head; //error recovery
  2481             private TypeSymbol makeNotionalInterface(IntersectionClassType ict) {
  2482                 ListBuffer<Type> targs = new ListBuffer<>();
  2483                 ListBuffer<Type> supertypes = new ListBuffer<>();
  2484                 for (Type i : ict.interfaces_field) {
  2485                     if (i.isParameterized()) {
  2486                         targs.appendList(i.tsym.type.allparams());
  2488                     supertypes.append(i.tsym.type);
  2490                 IntersectionClassType notionalIntf = types.makeIntersectionType(supertypes.toList());
  2491                 notionalIntf.allparams_field = targs.toList();
  2492                 notionalIntf.tsym.flags_field |= INTERFACE;
  2493                 return notionalIntf.tsym;
  2496             private void reportIntersectionError(DiagnosticPosition pos, String key, Object... args) {
  2497                 resultInfo.checkContext.report(pos, diags.fragment("bad.intersection.target.for.functional.expr",
  2498                         diags.fragment(key, args)));
  2500         };
  2502         private Type fallbackDescriptorType(JCExpression tree) {
  2503             switch (tree.getTag()) {
  2504                 case LAMBDA:
  2505                     JCLambda lambda = (JCLambda)tree;
  2506                     List<Type> argtypes = List.nil();
  2507                     for (JCVariableDecl param : lambda.params) {
  2508                         argtypes = param.vartype != null ?
  2509                                 argtypes.append(param.vartype.type) :
  2510                                 argtypes.append(syms.errType);
  2512                     return new MethodType(argtypes, Type.recoveryType,
  2513                             List.of(syms.throwableType), syms.methodClass);
  2514                 case REFERENCE:
  2515                     return new MethodType(List.<Type>nil(), Type.recoveryType,
  2516                             List.of(syms.throwableType), syms.methodClass);
  2517                 default:
  2518                     Assert.error("Cannot get here!");
  2520             return null;
  2523         private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env,
  2524                 final InferenceContext inferenceContext, final Type... ts) {
  2525             checkAccessibleTypes(pos, env, inferenceContext, List.from(ts));
  2528         private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env,
  2529                 final InferenceContext inferenceContext, final List<Type> ts) {
  2530             if (inferenceContext.free(ts)) {
  2531                 inferenceContext.addFreeTypeListener(ts, new FreeTypeListener() {
  2532                     @Override
  2533                     public void typesInferred(InferenceContext inferenceContext) {
  2534                         checkAccessibleTypes(pos, env, inferenceContext, inferenceContext.asInstTypes(ts));
  2536                 });
  2537             } else {
  2538                 for (Type t : ts) {
  2539                     rs.checkAccessibleType(env, t);
  2544         /**
  2545          * Lambda/method reference have a special check context that ensures
  2546          * that i.e. a lambda return type is compatible with the expected
  2547          * type according to both the inherited context and the assignment
  2548          * context.
  2549          */
  2550         class FunctionalReturnContext extends Check.NestedCheckContext {
  2552             FunctionalReturnContext(CheckContext enclosingContext) {
  2553                 super(enclosingContext);
  2556             @Override
  2557             public boolean compatible(Type found, Type req, Warner warn) {
  2558                 //return type must be compatible in both current context and assignment context
  2559                 return chk.basicHandler.compatible(found, inferenceContext().asUndetVar(req), warn);
  2562             @Override
  2563             public void report(DiagnosticPosition pos, JCDiagnostic details) {
  2564                 enclosingContext.report(pos, diags.fragment("incompatible.ret.type.in.lambda", details));
  2568         class ExpressionLambdaReturnContext extends FunctionalReturnContext {
  2570             JCExpression expr;
  2572             ExpressionLambdaReturnContext(JCExpression expr, CheckContext enclosingContext) {
  2573                 super(enclosingContext);
  2574                 this.expr = expr;
  2577             @Override
  2578             public boolean compatible(Type found, Type req, Warner warn) {
  2579                 //a void return is compatible with an expression statement lambda
  2580                 return TreeInfo.isExpressionStatement(expr) && req.hasTag(VOID) ||
  2581                         super.compatible(found, req, warn);
  2585         /**
  2586         * Lambda compatibility. Check that given return types, thrown types, parameter types
  2587         * are compatible with the expected functional interface descriptor. This means that:
  2588         * (i) parameter types must be identical to those of the target descriptor; (ii) return
  2589         * types must be compatible with the return type of the expected descriptor.
  2590         */
  2591         private void checkLambdaCompatible(JCLambda tree, Type descriptor, CheckContext checkContext) {
  2592             Type returnType = checkContext.inferenceContext().asUndetVar(descriptor.getReturnType());
  2594             //return values have already been checked - but if lambda has no return
  2595             //values, we must ensure that void/value compatibility is correct;
  2596             //this amounts at checking that, if a lambda body can complete normally,
  2597             //the descriptor's return type must be void
  2598             if (tree.getBodyKind() == JCLambda.BodyKind.STATEMENT && tree.canCompleteNormally &&
  2599                     !returnType.hasTag(VOID) && returnType != Type.recoveryType) {
  2600                 checkContext.report(tree, diags.fragment("incompatible.ret.type.in.lambda",
  2601                         diags.fragment("missing.ret.val", returnType)));
  2604             List<Type> argTypes = checkContext.inferenceContext().asUndetVars(descriptor.getParameterTypes());
  2605             if (!types.isSameTypes(argTypes, TreeInfo.types(tree.params))) {
  2606                 checkContext.report(tree, diags.fragment("incompatible.arg.types.in.lambda"));
  2610         /* Map to hold 'fake' clinit methods. If a lambda is used to initialize a
  2611          * static field and that lambda has type annotations, these annotations will
  2612          * also be stored at these fake clinit methods.
  2614          * LambdaToMethod also use fake clinit methods so they can be reused.
  2615          * Also as LTM is a phase subsequent to attribution, the methods from
  2616          * clinits can be safely removed by LTM to save memory.
  2617          */
  2618         private Map<ClassSymbol, MethodSymbol> clinits = new HashMap<>();
  2620         public MethodSymbol removeClinit(ClassSymbol sym) {
  2621             return clinits.remove(sym);
  2624         /* This method returns an environment to be used to attribute a lambda
  2625          * expression.
  2627          * The owner of this environment is a method symbol. If the current owner
  2628          * is not a method, for example if the lambda is used to initialize
  2629          * a field, then if the field is:
  2631          * - an instance field, we use the first constructor.
  2632          * - a static field, we create a fake clinit method.
  2633          */
  2634         public Env<AttrContext> lambdaEnv(JCLambda that, Env<AttrContext> env) {
  2635             Env<AttrContext> lambdaEnv;
  2636             Symbol owner = env.info.scope.owner;
  2637             if (owner.kind == VAR && owner.owner.kind == TYP) {
  2638                 //field initializer
  2639                 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dupUnshared()));
  2640                 ClassSymbol enclClass = owner.enclClass();
  2641                 /* if the field isn't static, then we can get the first constructor
  2642                  * and use it as the owner of the environment. This is what
  2643                  * LTM code is doing to look for type annotations so we are fine.
  2644                  */
  2645                 if ((owner.flags() & STATIC) == 0) {
  2646                     for (Symbol s : enclClass.members_field.getElementsByName(names.init)) {
  2647                         lambdaEnv.info.scope.owner = s;
  2648                         break;
  2650                 } else {
  2651                     /* if the field is static then we need to create a fake clinit
  2652                      * method, this method can later be reused by LTM.
  2653                      */
  2654                     MethodSymbol clinit = clinits.get(enclClass);
  2655                     if (clinit == null) {
  2656                         Type clinitType = new MethodType(List.<Type>nil(),
  2657                                 syms.voidType, List.<Type>nil(), syms.methodClass);
  2658                         clinit = new MethodSymbol(STATIC | SYNTHETIC | PRIVATE,
  2659                                 names.clinit, clinitType, enclClass);
  2660                         clinit.params = List.<VarSymbol>nil();
  2661                         clinits.put(enclClass, clinit);
  2663                     lambdaEnv.info.scope.owner = clinit;
  2665             } else {
  2666                 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dup()));
  2668             return lambdaEnv;
  2671     @Override
  2672     public void visitReference(final JCMemberReference that) {
  2673         if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) {
  2674             if (pt().hasTag(NONE)) {
  2675                 //method reference only allowed in assignment or method invocation/cast context
  2676                 log.error(that.pos(), "unexpected.mref");
  2678             result = that.type = types.createErrorType(pt());
  2679             return;
  2681         final Env<AttrContext> localEnv = env.dup(that);
  2682         try {
  2683             //attribute member reference qualifier - if this is a constructor
  2684             //reference, the expected kind must be a type
  2685             Type exprType = attribTree(that.expr, env, memberReferenceQualifierResult(that));
  2687             if (that.getMode() == JCMemberReference.ReferenceMode.NEW) {
  2688                 exprType = chk.checkConstructorRefType(that.expr, exprType);
  2689                 if (!exprType.isErroneous() &&
  2690                     exprType.isRaw() &&
  2691                     that.typeargs != null) {
  2692                     log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()),
  2693                         diags.fragment("mref.infer.and.explicit.params"));
  2694                     exprType = types.createErrorType(exprType);
  2698             if (exprType.isErroneous()) {
  2699                 //if the qualifier expression contains problems,
  2700                 //give up attribution of method reference
  2701                 result = that.type = exprType;
  2702                 return;
  2705             if (TreeInfo.isStaticSelector(that.expr, names)) {
  2706                 //if the qualifier is a type, validate it; raw warning check is
  2707                 //omitted as we don't know at this stage as to whether this is a
  2708                 //raw selector (because of inference)
  2709                 chk.validate(that.expr, env, false);
  2712             //attrib type-arguments
  2713             List<Type> typeargtypes = List.nil();
  2714             if (that.typeargs != null) {
  2715                 typeargtypes = attribTypes(that.typeargs, localEnv);
  2718             Type desc;
  2719             Type currentTarget = pt();
  2720             boolean isTargetSerializable =
  2721                     resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK &&
  2722                     isSerializable(currentTarget);
  2723             if (currentTarget != Type.recoveryType) {
  2724                 currentTarget = types.removeWildcards(targetChecker.visit(currentTarget, that));
  2725                 desc = types.findDescriptorType(currentTarget);
  2726             } else {
  2727                 currentTarget = Type.recoveryType;
  2728                 desc = fallbackDescriptorType(that);
  2731             setFunctionalInfo(localEnv, that, pt(), desc, currentTarget, resultInfo.checkContext);
  2732             List<Type> argtypes = desc.getParameterTypes();
  2733             Resolve.MethodCheck referenceCheck = rs.resolveMethodCheck;
  2735             if (resultInfo.checkContext.inferenceContext().free(argtypes)) {
  2736                 referenceCheck = rs.new MethodReferenceCheck(resultInfo.checkContext.inferenceContext());
  2739             Pair<Symbol, Resolve.ReferenceLookupHelper> refResult = null;
  2740             List<Type> saved_undet = resultInfo.checkContext.inferenceContext().save();
  2741             try {
  2742                 refResult = rs.resolveMemberReference(localEnv, that, that.expr.type,
  2743                         that.name, argtypes, typeargtypes, referenceCheck,
  2744                         resultInfo.checkContext.inferenceContext(),
  2745                         resultInfo.checkContext.deferredAttrContext().mode);
  2746             } finally {
  2747                 resultInfo.checkContext.inferenceContext().rollback(saved_undet);
  2750             Symbol refSym = refResult.fst;
  2751             Resolve.ReferenceLookupHelper lookupHelper = refResult.snd;
  2753             if (refSym.kind != MTH) {
  2754                 boolean targetError;
  2755                 switch (refSym.kind) {
  2756                     case ABSENT_MTH:
  2757                         targetError = false;
  2758                         break;
  2759                     case WRONG_MTH:
  2760                     case WRONG_MTHS:
  2761                     case AMBIGUOUS:
  2762                     case HIDDEN:
  2763                     case STATICERR:
  2764                     case MISSING_ENCL:
  2765                     case WRONG_STATICNESS:
  2766                         targetError = true;
  2767                         break;
  2768                     default:
  2769                         Assert.error("unexpected result kind " + refSym.kind);
  2770                         targetError = false;
  2773                 JCDiagnostic detailsDiag = ((Resolve.ResolveError)refSym.baseSymbol()).getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT,
  2774                                 that, exprType.tsym, exprType, that.name, argtypes, typeargtypes);
  2776                 JCDiagnostic.DiagnosticType diagKind = targetError ?
  2777                         JCDiagnostic.DiagnosticType.FRAGMENT : JCDiagnostic.DiagnosticType.ERROR;
  2779                 JCDiagnostic diag = diags.create(diagKind, log.currentSource(), that,
  2780                         "invalid.mref", Kinds.kindName(that.getMode()), detailsDiag);
  2782                 if (targetError && currentTarget == Type.recoveryType) {
  2783                     //a target error doesn't make sense during recovery stage
  2784                     //as we don't know what actual parameter types are
  2785                     result = that.type = currentTarget;
  2786                     return;
  2787                 } else {
  2788                     if (targetError) {
  2789                         resultInfo.checkContext.report(that, diag);
  2790                     } else {
  2791                         log.report(diag);
  2793                     result = that.type = types.createErrorType(currentTarget);
  2794                     return;
  2798             that.sym = refSym.baseSymbol();
  2799             that.kind = lookupHelper.referenceKind(that.sym);
  2800             that.ownerAccessible = rs.isAccessible(localEnv, that.sym.enclClass());
  2802             if (desc.getReturnType() == Type.recoveryType) {
  2803                 // stop here
  2804                 result = that.type = currentTarget;
  2805                 return;
  2808             if (resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) {
  2810                 if (that.getMode() == ReferenceMode.INVOKE &&
  2811                         TreeInfo.isStaticSelector(that.expr, names) &&
  2812                         that.kind.isUnbound() &&
  2813                         !desc.getParameterTypes().head.isParameterized()) {
  2814                     chk.checkRaw(that.expr, localEnv);
  2817                 if (that.sym.isStatic() && TreeInfo.isStaticSelector(that.expr, names) &&
  2818                         exprType.getTypeArguments().nonEmpty()) {
  2819                     //static ref with class type-args
  2820                     log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()),
  2821                             diags.fragment("static.mref.with.targs"));
  2822                     result = that.type = types.createErrorType(currentTarget);
  2823                     return;
  2826                 if (that.sym.isStatic() && !TreeInfo.isStaticSelector(that.expr, names) &&
  2827                         !that.kind.isUnbound()) {
  2828                     //no static bound mrefs
  2829                     log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()),
  2830                             diags.fragment("static.bound.mref"));
  2831                     result = that.type = types.createErrorType(currentTarget);
  2832                     return;
  2835                 if (!refSym.isStatic() && that.kind == JCMemberReference.ReferenceKind.SUPER) {
  2836                     // Check that super-qualified symbols are not abstract (JLS)
  2837                     rs.checkNonAbstract(that.pos(), that.sym);
  2840                 if (isTargetSerializable) {
  2841                     chk.checkElemAccessFromSerializableLambda(that);
  2845             ResultInfo checkInfo =
  2846                     resultInfo.dup(newMethodTemplate(
  2847                         desc.getReturnType().hasTag(VOID) ? Type.noType : desc.getReturnType(),
  2848                         that.kind.isUnbound() ? argtypes.tail : argtypes, typeargtypes),
  2849                         new FunctionalReturnContext(resultInfo.checkContext));
  2851             Type refType = checkId(noCheckTree, lookupHelper.site, refSym, localEnv, checkInfo);
  2853             if (that.kind.isUnbound() &&
  2854                     resultInfo.checkContext.inferenceContext().free(argtypes.head)) {
  2855                 //re-generate inference constraints for unbound receiver
  2856                 if (!types.isSubtype(resultInfo.checkContext.inferenceContext().asUndetVar(argtypes.head), exprType)) {
  2857                     //cannot happen as this has already been checked - we just need
  2858                     //to regenerate the inference constraints, as that has been lost
  2859                     //as a result of the call to inferenceContext.save()
  2860                     Assert.error("Can't get here");
  2864             if (!refType.isErroneous()) {
  2865                 refType = types.createMethodTypeWithReturn(refType,
  2866                         adjustMethodReturnType(lookupHelper.site, that.name, checkInfo.pt.getParameterTypes(), refType.getReturnType()));
  2869             //go ahead with standard method reference compatibility check - note that param check
  2870             //is a no-op (as this has been taken care during method applicability)
  2871             boolean isSpeculativeRound =
  2872                     resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE;
  2874             that.type = currentTarget; //avoids recovery at this stage
  2875             checkReferenceCompatible(that, desc, refType, resultInfo.checkContext, isSpeculativeRound);
  2876             if (!isSpeculativeRound) {
  2877                 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), desc, currentTarget);
  2879             result = check(that, currentTarget, VAL, resultInfo);
  2880         } catch (Types.FunctionDescriptorLookupError ex) {
  2881             JCDiagnostic cause = ex.getDiagnostic();
  2882             resultInfo.checkContext.report(that, cause);
  2883             result = that.type = types.createErrorType(pt());
  2884             return;
  2887     //where
  2888         ResultInfo memberReferenceQualifierResult(JCMemberReference tree) {
  2889             //if this is a constructor reference, the expected kind must be a type
  2890             return new ResultInfo(tree.getMode() == ReferenceMode.INVOKE ? VAL | TYP : TYP, Type.noType);
  2894     @SuppressWarnings("fallthrough")
  2895     void checkReferenceCompatible(JCMemberReference tree, Type descriptor, Type refType, CheckContext checkContext, boolean speculativeAttr) {
  2896         Type returnType = checkContext.inferenceContext().asUndetVar(descriptor.getReturnType());
  2898         Type resType;
  2899         switch (tree.getMode()) {
  2900             case NEW:
  2901                 if (!tree.expr.type.isRaw()) {
  2902                     resType = tree.expr.type;
  2903                     break;
  2905             default:
  2906                 resType = refType.getReturnType();
  2909         Type incompatibleReturnType = resType;
  2911         if (returnType.hasTag(VOID)) {
  2912             incompatibleReturnType = null;
  2915         if (!returnType.hasTag(VOID) && !resType.hasTag(VOID)) {
  2916             if (resType.isErroneous() ||
  2917                     new FunctionalReturnContext(checkContext).compatible(resType, returnType, types.noWarnings)) {
  2918                 incompatibleReturnType = null;
  2922         if (incompatibleReturnType != null) {
  2923             checkContext.report(tree, diags.fragment("incompatible.ret.type.in.mref",
  2924                     diags.fragment("inconvertible.types", resType, descriptor.getReturnType())));
  2927         if (!speculativeAttr) {
  2928             List<Type> thrownTypes = checkContext.inferenceContext().asUndetVars(descriptor.getThrownTypes());
  2929             if (chk.unhandled(refType.getThrownTypes(), thrownTypes).nonEmpty()) {
  2930                 log.error(tree, "incompatible.thrown.types.in.mref", refType.getThrownTypes());
  2935     /**
  2936      * Set functional type info on the underlying AST. Note: as the target descriptor
  2937      * might contain inference variables, we might need to register an hook in the
  2938      * current inference context.
  2939      */
  2940     private void setFunctionalInfo(final Env<AttrContext> env, final JCFunctionalExpression fExpr,
  2941             final Type pt, final Type descriptorType, final Type primaryTarget, final CheckContext checkContext) {
  2942         if (checkContext.inferenceContext().free(descriptorType)) {
  2943             checkContext.inferenceContext().addFreeTypeListener(List.of(pt, descriptorType), new FreeTypeListener() {
  2944                 public void typesInferred(InferenceContext inferenceContext) {
  2945                     setFunctionalInfo(env, fExpr, pt, inferenceContext.asInstType(descriptorType),
  2946                             inferenceContext.asInstType(primaryTarget), checkContext);
  2948             });
  2949         } else {
  2950             ListBuffer<Type> targets = new ListBuffer<>();
  2951             if (pt.hasTag(CLASS)) {
  2952                 if (pt.isCompound()) {
  2953                     targets.append(types.removeWildcards(primaryTarget)); //this goes first
  2954                     for (Type t : ((IntersectionClassType)pt()).interfaces_field) {
  2955                         if (t != primaryTarget) {
  2956                             targets.append(types.removeWildcards(t));
  2959                 } else {
  2960                     targets.append(types.removeWildcards(primaryTarget));
  2963             fExpr.targets = targets.toList();
  2964             if (checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK &&
  2965                     pt != Type.recoveryType) {
  2966                 //check that functional interface class is well-formed
  2967                 try {
  2968                     /* Types.makeFunctionalInterfaceClass() may throw an exception
  2969                      * when it's executed post-inference. See the listener code
  2970                      * above.
  2971                      */
  2972                     ClassSymbol csym = types.makeFunctionalInterfaceClass(env,
  2973                             names.empty, List.of(fExpr.targets.head), ABSTRACT);
  2974                     if (csym != null) {
  2975                         chk.checkImplementations(env.tree, csym, csym);
  2977                 } catch (Types.FunctionDescriptorLookupError ex) {
  2978                     JCDiagnostic cause = ex.getDiagnostic();
  2979                     resultInfo.checkContext.report(env.tree, cause);
  2985     public void visitParens(JCParens tree) {
  2986         Type owntype = attribTree(tree.expr, env, resultInfo);
  2987         result = check(tree, owntype, pkind(), resultInfo);
  2988         Symbol sym = TreeInfo.symbol(tree);
  2989         if (sym != null && (sym.kind&(TYP|PCK)) != 0)
  2990             log.error(tree.pos(), "illegal.start.of.type");
  2993     public void visitAssign(JCAssign tree) {
  2994         Type owntype = attribTree(tree.lhs, env.dup(tree), varInfo);
  2995         Type capturedType = capture(owntype);
  2996         attribExpr(tree.rhs, env, owntype);
  2997         result = check(tree, capturedType, VAL, resultInfo);
  3000     public void visitAssignop(JCAssignOp tree) {
  3001         // Attribute arguments.
  3002         Type owntype = attribTree(tree.lhs, env, varInfo);
  3003         Type operand = attribExpr(tree.rhs, env);
  3004         // Find operator.
  3005         Symbol operator = tree.operator = rs.resolveBinaryOperator(
  3006             tree.pos(), tree.getTag().noAssignOp(), env,
  3007             owntype, operand);
  3009         if (operator.kind == MTH &&
  3010                 !owntype.isErroneous() &&
  3011                 !operand.isErroneous()) {
  3012             chk.checkOperator(tree.pos(),
  3013                               (OperatorSymbol)operator,
  3014                               tree.getTag().noAssignOp(),
  3015                               owntype,
  3016                               operand);
  3017             chk.checkDivZero(tree.rhs.pos(), operator, operand);
  3018             chk.checkCastable(tree.rhs.pos(),
  3019                               operator.type.getReturnType(),
  3020                               owntype);
  3022         result = check(tree, owntype, VAL, resultInfo);
  3025     public void visitUnary(JCUnary tree) {
  3026         // Attribute arguments.
  3027         Type argtype = (tree.getTag().isIncOrDecUnaryOp())
  3028             ? attribTree(tree.arg, env, varInfo)
  3029             : chk.checkNonVoid(tree.arg.pos(), attribExpr(tree.arg, env));
  3031         // Find operator.
  3032         Symbol operator = tree.operator =
  3033             rs.resolveUnaryOperator(tree.pos(), tree.getTag(), env, argtype);
  3035         Type owntype = types.createErrorType(tree.type);
  3036         if (operator.kind == MTH &&
  3037                 !argtype.isErroneous()) {
  3038             owntype = (tree.getTag().isIncOrDecUnaryOp())
  3039                 ? tree.arg.type
  3040                 : operator.type.getReturnType();
  3041             int opc = ((OperatorSymbol)operator).opcode;
  3043             // If the argument is constant, fold it.
  3044             if (argtype.constValue() != null) {
  3045                 Type ctype = cfolder.fold1(opc, argtype);
  3046                 if (ctype != null) {
  3047                     owntype = cfolder.coerce(ctype, owntype);
  3051         result = check(tree, owntype, VAL, resultInfo);
  3054     public void visitBinary(JCBinary tree) {
  3055         // Attribute arguments.
  3056         Type left = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.lhs, env));
  3057         Type right = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.rhs, env));
  3059         // Find operator.
  3060         Symbol operator = tree.operator =
  3061             rs.resolveBinaryOperator(tree.pos(), tree.getTag(), env, left, right);
  3063         Type owntype = types.createErrorType(tree.type);
  3064         if (operator.kind == MTH &&
  3065                 !left.isErroneous() &&
  3066                 !right.isErroneous()) {
  3067             owntype = operator.type.getReturnType();
  3068             // This will figure out when unboxing can happen and
  3069             // choose the right comparison operator.
  3070             int opc = chk.checkOperator(tree.lhs.pos(),
  3071                                         (OperatorSymbol)operator,
  3072                                         tree.getTag(),
  3073                                         left,
  3074                                         right);
  3076             // If both arguments are constants, fold them.
  3077             if (left.constValue() != null && right.constValue() != null) {
  3078                 Type ctype = cfolder.fold2(opc, left, right);
  3079                 if (ctype != null) {
  3080                     owntype = cfolder.coerce(ctype, owntype);
  3084             // Check that argument types of a reference ==, != are
  3085             // castable to each other, (JLS 15.21).  Note: unboxing
  3086             // comparisons will not have an acmp* opc at this point.
  3087             if ((opc == ByteCodes.if_acmpeq || opc == ByteCodes.if_acmpne)) {
  3088                 if (!types.isEqualityComparable(left, right,
  3089                                                 new Warner(tree.pos()))) {
  3090                     log.error(tree.pos(), "incomparable.types", left, right);
  3094             chk.checkDivZero(tree.rhs.pos(), operator, right);
  3096         result = check(tree, owntype, VAL, resultInfo);
  3099     public void visitTypeCast(final JCTypeCast tree) {
  3100         Type clazztype = attribType(tree.clazz, env);
  3101         chk.validate(tree.clazz, env, false);
  3102         //a fresh environment is required for 292 inference to work properly ---
  3103         //see Infer.instantiatePolymorphicSignatureInstance()
  3104         Env<AttrContext> localEnv = env.dup(tree);
  3105         //should we propagate the target type?
  3106         final ResultInfo castInfo;
  3107         JCExpression expr = TreeInfo.skipParens(tree.expr);
  3108         boolean isPoly = allowPoly && (expr.hasTag(LAMBDA) || expr.hasTag(REFERENCE));
  3109         if (isPoly) {
  3110             //expression is a poly - we need to propagate target type info
  3111             castInfo = new ResultInfo(VAL, clazztype, new Check.NestedCheckContext(resultInfo.checkContext) {
  3112                 @Override
  3113                 public boolean compatible(Type found, Type req, Warner warn) {
  3114                     return types.isCastable(found, req, warn);
  3116             });
  3117         } else {
  3118             //standalone cast - target-type info is not propagated
  3119             castInfo = unknownExprInfo;
  3121         Type exprtype = attribTree(tree.expr, localEnv, castInfo);
  3122         Type owntype = isPoly ? clazztype : chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
  3123         if (exprtype.constValue() != null)
  3124             owntype = cfolder.coerce(exprtype, owntype);
  3125         result = check(tree, capture(owntype), VAL, resultInfo);
  3126         if (!isPoly)
  3127             chk.checkRedundantCast(localEnv, tree);
  3130     public void visitTypeTest(JCInstanceOf tree) {
  3131         Type exprtype = chk.checkNullOrRefType(
  3132             tree.expr.pos(), attribExpr(tree.expr, env));
  3133         Type clazztype = attribType(tree.clazz, env);
  3134         if (!clazztype.hasTag(TYPEVAR)) {
  3135             clazztype = chk.checkClassOrArrayType(tree.clazz.pos(), clazztype);
  3137         if (!clazztype.isErroneous() && !types.isReifiable(clazztype)) {
  3138             log.error(tree.clazz.pos(), "illegal.generic.type.for.instof");
  3139             clazztype = types.createErrorType(clazztype);
  3141         chk.validate(tree.clazz, env, false);
  3142         chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
  3143         result = check(tree, syms.booleanType, VAL, resultInfo);
  3146     public void visitIndexed(JCArrayAccess tree) {
  3147         Type owntype = types.createErrorType(tree.type);
  3148         Type atype = attribExpr(tree.indexed, env);
  3149         attribExpr(tree.index, env, syms.intType);
  3150         if (types.isArray(atype))
  3151             owntype = types.elemtype(atype);
  3152         else if (!atype.hasTag(ERROR))
  3153             log.error(tree.pos(), "array.req.but.found", atype);
  3154         if ((pkind() & VAR) == 0) owntype = capture(owntype);
  3155         result = check(tree, owntype, VAR, resultInfo);
  3158     public void visitIdent(JCIdent tree) {
  3159         Symbol sym;
  3161         // Find symbol
  3162         if (pt().hasTag(METHOD) || pt().hasTag(FORALL)) {
  3163             // If we are looking for a method, the prototype `pt' will be a
  3164             // method type with the type of the call's arguments as parameters.
  3165             env.info.pendingResolutionPhase = null;
  3166             sym = rs.resolveMethod(tree.pos(), env, tree.name, pt().getParameterTypes(), pt().getTypeArguments());
  3167         } else if (tree.sym != null && tree.sym.kind != VAR) {
  3168             sym = tree.sym;
  3169         } else {
  3170             sym = rs.resolveIdent(tree.pos(), env, tree.name, pkind());
  3172         tree.sym = sym;
  3174         // (1) Also find the environment current for the class where
  3175         //     sym is defined (`symEnv').
  3176         // Only for pre-tiger versions (1.4 and earlier):
  3177         // (2) Also determine whether we access symbol out of an anonymous
  3178         //     class in a this or super call.  This is illegal for instance
  3179         //     members since such classes don't carry a this$n link.
  3180         //     (`noOuterThisPath').
  3181         Env<AttrContext> symEnv = env;
  3182         boolean noOuterThisPath = false;
  3183         if (env.enclClass.sym.owner.kind != PCK && // we are in an inner class
  3184             (sym.kind & (VAR | MTH | TYP)) != 0 &&
  3185             sym.owner.kind == TYP &&
  3186             tree.name != names._this && tree.name != names._super) {
  3188             // Find environment in which identifier is defined.
  3189             while (symEnv.outer != null &&
  3190                    !sym.isMemberOf(symEnv.enclClass.sym, types)) {
  3191                 if ((symEnv.enclClass.sym.flags() & NOOUTERTHIS) != 0)
  3192                     noOuterThisPath = !allowAnonOuterThis;
  3193                 symEnv = symEnv.outer;
  3197         // If symbol is a variable, ...
  3198         if (sym.kind == VAR) {
  3199             VarSymbol v = (VarSymbol)sym;
  3201             // ..., evaluate its initializer, if it has one, and check for
  3202             // illegal forward reference.
  3203             checkInit(tree, env, v, false);
  3205             // If we are expecting a variable (as opposed to a value), check
  3206             // that the variable is assignable in the current environment.
  3207             if (pkind() == VAR)
  3208                 checkAssignable(tree.pos(), v, null, env);
  3211         // In a constructor body,
  3212         // if symbol is a field or instance method, check that it is
  3213         // not accessed before the supertype constructor is called.
  3214         if ((symEnv.info.isSelfCall || noOuterThisPath) &&
  3215             (sym.kind & (VAR | MTH)) != 0 &&
  3216             sym.owner.kind == TYP &&
  3217             (sym.flags() & STATIC) == 0) {
  3218             chk.earlyRefError(tree.pos(), sym.kind == VAR ? sym : thisSym(tree.pos(), env));
  3220         Env<AttrContext> env1 = env;
  3221         if (sym.kind != ERR && sym.kind != TYP && sym.owner != null && sym.owner != env1.enclClass.sym) {
  3222             // If the found symbol is inaccessible, then it is
  3223             // accessed through an enclosing instance.  Locate this
  3224             // enclosing instance:
  3225             while (env1.outer != null && !rs.isAccessible(env, env1.enclClass.sym.type, sym))
  3226                 env1 = env1.outer;
  3229         if (env.info.isSerializable) {
  3230             chk.checkElemAccessFromSerializableLambda(tree);
  3233         result = checkId(tree, env1.enclClass.sym.type, sym, env, resultInfo);
  3236     public void visitSelect(JCFieldAccess tree) {
  3237         // Determine the expected kind of the qualifier expression.
  3238         int skind = 0;
  3239         if (tree.name == names._this || tree.name == names._super ||
  3240             tree.name == names._class)
  3242             skind = TYP;
  3243         } else {
  3244             if ((pkind() & PCK) != 0) skind = skind | PCK;
  3245             if ((pkind() & TYP) != 0) skind = skind | TYP | PCK;
  3246             if ((pkind() & (VAL | MTH)) != 0) skind = skind | VAL | TYP;
  3249         // Attribute the qualifier expression, and determine its symbol (if any).
  3250         Type site = attribTree(tree.selected, env, new ResultInfo(skind, Infer.anyPoly));
  3251         if ((pkind() & (PCK | TYP)) == 0)
  3252             site = capture(site); // Capture field access
  3254         // don't allow T.class T[].class, etc
  3255         if (skind == TYP) {
  3256             Type elt = site;
  3257             while (elt.hasTag(ARRAY))
  3258                 elt = ((ArrayType)elt.unannotatedType()).elemtype;
  3259             if (elt.hasTag(TYPEVAR)) {
  3260                 log.error(tree.pos(), "type.var.cant.be.deref");
  3261                 result = tree.type = types.createErrorType(tree.name, site.tsym, site);
  3262                 tree.sym = tree.type.tsym;
  3263                 return ;
  3267         // If qualifier symbol is a type or `super', assert `selectSuper'
  3268         // for the selection. This is relevant for determining whether
  3269         // protected symbols are accessible.
  3270         Symbol sitesym = TreeInfo.symbol(tree.selected);
  3271         boolean selectSuperPrev = env.info.selectSuper;
  3272         env.info.selectSuper =
  3273             sitesym != null &&
  3274             sitesym.name == names._super;
  3276         // Determine the symbol represented by the selection.
  3277         env.info.pendingResolutionPhase = null;
  3278         Symbol sym = selectSym(tree, sitesym, site, env, resultInfo);
  3279         if (sym.kind == VAR && sym.name != names._super && env.info.defaultSuperCallSite != null) {
  3280             log.error(tree.selected.pos(), "not.encl.class", site.tsym);
  3281             sym = syms.errSymbol;
  3283         if (sym.exists() && !isType(sym) && (pkind() & (PCK | TYP)) != 0) {
  3284             site = capture(site);
  3285             sym = selectSym(tree, sitesym, site, env, resultInfo);
  3287         boolean varArgs = env.info.lastResolveVarargs();
  3288         tree.sym = sym;
  3290         if (site.hasTag(TYPEVAR) && !isType(sym) && sym.kind != ERR) {
  3291             while (site.hasTag(TYPEVAR)) site = site.getUpperBound();
  3292             site = capture(site);
  3295         // If that symbol is a variable, ...
  3296         if (sym.kind == VAR) {
  3297             VarSymbol v = (VarSymbol)sym;
  3299             // ..., evaluate its initializer, if it has one, and check for
  3300             // illegal forward reference.
  3301             checkInit(tree, env, v, true);
  3303             // If we are expecting a variable (as opposed to a value), check
  3304             // that the variable is assignable in the current environment.
  3305             if (pkind() == VAR)
  3306                 checkAssignable(tree.pos(), v, tree.selected, env);
  3309         if (sitesym != null &&
  3310                 sitesym.kind == VAR &&
  3311                 ((VarSymbol)sitesym).isResourceVariable() &&
  3312                 sym.kind == MTH &&
  3313                 sym.name.equals(names.close) &&
  3314                 sym.overrides(syms.autoCloseableClose, sitesym.type.tsym, types, true) &&
  3315                 env.info.lint.isEnabled(LintCategory.TRY)) {
  3316             log.warning(LintCategory.TRY, tree, "try.explicit.close.call");
  3319         // Disallow selecting a type from an expression
  3320         if (isType(sym) && (sitesym==null || (sitesym.kind&(TYP|PCK)) == 0)) {
  3321             tree.type = check(tree.selected, pt(),
  3322                               sitesym == null ? VAL : sitesym.kind, new ResultInfo(TYP|PCK, pt()));
  3325         if (isType(sitesym)) {
  3326             if (sym.name == names._this) {
  3327                 // If `C' is the currently compiled class, check that
  3328                 // C.this' does not appear in a call to a super(...)
  3329                 if (env.info.isSelfCall &&
  3330                     site.tsym == env.enclClass.sym) {
  3331                     chk.earlyRefError(tree.pos(), sym);
  3333             } else {
  3334                 // Check if type-qualified fields or methods are static (JLS)
  3335                 if ((sym.flags() & STATIC) == 0 &&
  3336                     !env.next.tree.hasTag(REFERENCE) &&
  3337                     sym.name != names._super &&
  3338                     (sym.kind == VAR || sym.kind == MTH)) {
  3339                     rs.accessBase(rs.new StaticError(sym),
  3340                               tree.pos(), site, sym.name, true);
  3343             if (!allowStaticInterfaceMethods && sitesym.isInterface() &&
  3344                     sym.isStatic() && sym.kind == MTH) {
  3345                 log.error(tree.pos(), "static.intf.method.invoke.not.supported.in.source", sourceName);
  3347         } else if (sym.kind != ERR && (sym.flags() & STATIC) != 0 && sym.name != names._class) {
  3348             // If the qualified item is not a type and the selected item is static, report
  3349             // a warning. Make allowance for the class of an array type e.g. Object[].class)
  3350             chk.warnStatic(tree, "static.not.qualified.by.type", Kinds.kindName(sym.kind), sym.owner);
  3353         // If we are selecting an instance member via a `super', ...
  3354         if (env.info.selectSuper && (sym.flags() & STATIC) == 0) {
  3356             // Check that super-qualified symbols are not abstract (JLS)
  3357             rs.checkNonAbstract(tree.pos(), sym);
  3359             if (site.isRaw()) {
  3360                 // Determine argument types for site.
  3361                 Type site1 = types.asSuper(env.enclClass.sym.type, site.tsym);
  3362                 if (site1 != null) site = site1;
  3366         if (env.info.isSerializable) {
  3367             chk.checkElemAccessFromSerializableLambda(tree);
  3370         env.info.selectSuper = selectSuperPrev;
  3371         result = checkId(tree, site, sym, env, resultInfo);
  3373     //where
  3374         /** Determine symbol referenced by a Select expression,
  3376          *  @param tree   The select tree.
  3377          *  @param site   The type of the selected expression,
  3378          *  @param env    The current environment.
  3379          *  @param resultInfo The current result.
  3380          */
  3381         private Symbol selectSym(JCFieldAccess tree,
  3382                                  Symbol location,
  3383                                  Type site,
  3384                                  Env<AttrContext> env,
  3385                                  ResultInfo resultInfo) {
  3386             DiagnosticPosition pos = tree.pos();
  3387             Name name = tree.name;
  3388             switch (site.getTag()) {
  3389             case PACKAGE:
  3390                 return rs.accessBase(
  3391                     rs.findIdentInPackage(env, site.tsym, name, resultInfo.pkind),
  3392                     pos, location, site, name, true);
  3393             case ARRAY:
  3394             case CLASS:
  3395                 if (resultInfo.pt.hasTag(METHOD) || resultInfo.pt.hasTag(FORALL)) {
  3396                     return rs.resolveQualifiedMethod(
  3397                         pos, env, location, site, name, resultInfo.pt.getParameterTypes(), resultInfo.pt.getTypeArguments());
  3398                 } else if (name == names._this || name == names._super) {
  3399                     return rs.resolveSelf(pos, env, site.tsym, name);
  3400                 } else if (name == names._class) {
  3401                     // In this case, we have already made sure in
  3402                     // visitSelect that qualifier expression is a type.
  3403                     Type t = syms.classType;
  3404                     List<Type> typeargs = allowGenerics
  3405                         ? List.of(types.erasure(site))
  3406                         : List.<Type>nil();
  3407                     t = new ClassType(t.getEnclosingType(), typeargs, t.tsym);
  3408                     return new VarSymbol(
  3409                         STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
  3410                 } else {
  3411                     // We are seeing a plain identifier as selector.
  3412                     Symbol sym = rs.findIdentInType(env, site, name, resultInfo.pkind);
  3413                     if ((resultInfo.pkind & ERRONEOUS) == 0)
  3414                         sym = rs.accessBase(sym, pos, location, site, name, true);
  3415                     return sym;
  3417             case WILDCARD:
  3418                 throw new AssertionError(tree);
  3419             case TYPEVAR:
  3420                 // Normally, site.getUpperBound() shouldn't be null.
  3421                 // It should only happen during memberEnter/attribBase
  3422                 // when determining the super type which *must* beac
  3423                 // done before attributing the type variables.  In
  3424                 // other words, we are seeing this illegal program:
  3425                 // class B<T> extends A<T.foo> {}
  3426                 Symbol sym = (site.getUpperBound() != null)
  3427                     ? selectSym(tree, location, capture(site.getUpperBound()), env, resultInfo)
  3428                     : null;
  3429                 if (sym == null) {
  3430                     log.error(pos, "type.var.cant.be.deref");
  3431                     return syms.errSymbol;
  3432                 } else {
  3433                     Symbol sym2 = (sym.flags() & Flags.PRIVATE) != 0 ?
  3434                         rs.new AccessError(env, site, sym) :
  3435                                 sym;
  3436                     rs.accessBase(sym2, pos, location, site, name, true);
  3437                     return sym;
  3439             case ERROR:
  3440                 // preserve identifier names through errors
  3441                 return types.createErrorType(name, site.tsym, site).tsym;
  3442             default:
  3443                 // The qualifier expression is of a primitive type -- only
  3444                 // .class is allowed for these.
  3445                 if (name == names._class) {
  3446                     // In this case, we have already made sure in Select that
  3447                     // qualifier expression is a type.
  3448                     Type t = syms.classType;
  3449                     Type arg = types.boxedClass(site).type;
  3450                     t = new ClassType(t.getEnclosingType(), List.of(arg), t.tsym);
  3451                     return new VarSymbol(
  3452                         STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
  3453                 } else {
  3454                     log.error(pos, "cant.deref", site);
  3455                     return syms.errSymbol;
  3460         /** Determine type of identifier or select expression and check that
  3461          *  (1) the referenced symbol is not deprecated
  3462          *  (2) the symbol's type is safe (@see checkSafe)
  3463          *  (3) if symbol is a variable, check that its type and kind are
  3464          *      compatible with the prototype and protokind.
  3465          *  (4) if symbol is an instance field of a raw type,
  3466          *      which is being assigned to, issue an unchecked warning if its
  3467          *      type changes under erasure.
  3468          *  (5) if symbol is an instance method of a raw type, issue an
  3469          *      unchecked warning if its argument types change under erasure.
  3470          *  If checks succeed:
  3471          *    If symbol is a constant, return its constant type
  3472          *    else if symbol is a method, return its result type
  3473          *    otherwise return its type.
  3474          *  Otherwise return errType.
  3476          *  @param tree       The syntax tree representing the identifier
  3477          *  @param site       If this is a select, the type of the selected
  3478          *                    expression, otherwise the type of the current class.
  3479          *  @param sym        The symbol representing the identifier.
  3480          *  @param env        The current environment.
  3481          *  @param resultInfo    The expected result
  3482          */
  3483         Type checkId(JCTree tree,
  3484                      Type site,
  3485                      Symbol sym,
  3486                      Env<AttrContext> env,
  3487                      ResultInfo resultInfo) {
  3488             return (resultInfo.pt.hasTag(FORALL) || resultInfo.pt.hasTag(METHOD)) ?
  3489                     checkMethodId(tree, site, sym, env, resultInfo) :
  3490                     checkIdInternal(tree, site, sym, resultInfo.pt, env, resultInfo);
  3493         Type checkMethodId(JCTree tree,
  3494                      Type site,
  3495                      Symbol sym,
  3496                      Env<AttrContext> env,
  3497                      ResultInfo resultInfo) {
  3498             boolean isPolymorhicSignature =
  3499                 (sym.baseSymbol().flags() & SIGNATURE_POLYMORPHIC) != 0;
  3500             return isPolymorhicSignature ?
  3501                     checkSigPolyMethodId(tree, site, sym, env, resultInfo) :
  3502                     checkMethodIdInternal(tree, site, sym, env, resultInfo);
  3505         Type checkSigPolyMethodId(JCTree tree,
  3506                      Type site,
  3507                      Symbol sym,
  3508                      Env<AttrContext> env,
  3509                      ResultInfo resultInfo) {
  3510             //recover original symbol for signature polymorphic methods
  3511             checkMethodIdInternal(tree, site, sym.baseSymbol(), env, resultInfo);
  3512             env.info.pendingResolutionPhase = Resolve.MethodResolutionPhase.BASIC;
  3513             return sym.type;
  3516         Type checkMethodIdInternal(JCTree tree,
  3517                      Type site,
  3518                      Symbol sym,
  3519                      Env<AttrContext> env,
  3520                      ResultInfo resultInfo) {
  3521             if ((resultInfo.pkind & POLY) != 0) {
  3522                 Type pt = resultInfo.pt.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.SPECULATIVE, sym, env.info.pendingResolutionPhase));
  3523                 Type owntype = checkIdInternal(tree, site, sym, pt, env, resultInfo);
  3524                 resultInfo.pt.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.CHECK, sym, env.info.pendingResolutionPhase));
  3525                 return owntype;
  3526             } else {
  3527                 return checkIdInternal(tree, site, sym, resultInfo.pt, env, resultInfo);
  3531         Type checkIdInternal(JCTree tree,
  3532                      Type site,
  3533                      Symbol sym,
  3534                      Type pt,
  3535                      Env<AttrContext> env,
  3536                      ResultInfo resultInfo) {
  3537             if (pt.isErroneous()) {
  3538                 return types.createErrorType(site);
  3540             Type owntype; // The computed type of this identifier occurrence.
  3541             switch (sym.kind) {
  3542             case TYP:
  3543                 // For types, the computed type equals the symbol's type,
  3544                 // except for two situations:
  3545                 owntype = sym.type;
  3546                 if (owntype.hasTag(CLASS)) {
  3547                     chk.checkForBadAuxiliaryClassAccess(tree.pos(), env, (ClassSymbol)sym);
  3548                     Type ownOuter = owntype.getEnclosingType();
  3550                     // (a) If the symbol's type is parameterized, erase it
  3551                     // because no type parameters were given.
  3552                     // We recover generic outer type later in visitTypeApply.
  3553                     if (owntype.tsym.type.getTypeArguments().nonEmpty()) {
  3554                         owntype = types.erasure(owntype);
  3557                     // (b) If the symbol's type is an inner class, then
  3558                     // we have to interpret its outer type as a superclass
  3559                     // of the site type. Example:
  3560                     //
  3561                     // class Tree<A> { class Visitor { ... } }
  3562                     // class PointTree extends Tree<Point> { ... }
  3563                     // ...PointTree.Visitor...
  3564                     //
  3565                     // Then the type of the last expression above is
  3566                     // Tree<Point>.Visitor.
  3567                     else if (ownOuter.hasTag(CLASS) && site != ownOuter) {
  3568                         Type normOuter = site;
  3569                         if (normOuter.hasTag(CLASS)) {
  3570                             normOuter = types.asEnclosingSuper(site, ownOuter.tsym);
  3572                         if (normOuter == null) // perhaps from an import
  3573                             normOuter = types.erasure(ownOuter);
  3574                         if (normOuter != ownOuter)
  3575                             owntype = new ClassType(
  3576                                 normOuter, List.<Type>nil(), owntype.tsym);
  3579                 break;
  3580             case VAR:
  3581                 VarSymbol v = (VarSymbol)sym;
  3582                 // Test (4): if symbol is an instance field of a raw type,
  3583                 // which is being assigned to, issue an unchecked warning if
  3584                 // its type changes under erasure.
  3585                 if (allowGenerics &&
  3586                     resultInfo.pkind == VAR &&
  3587                     v.owner.kind == TYP &&
  3588                     (v.flags() & STATIC) == 0 &&
  3589                     (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) {
  3590                     Type s = types.asOuterSuper(site, v.owner);
  3591                     if (s != null &&
  3592                         s.isRaw() &&
  3593                         !types.isSameType(v.type, v.erasure(types))) {
  3594                         chk.warnUnchecked(tree.pos(),
  3595                                           "unchecked.assign.to.var",
  3596                                           v, s);
  3599                 // The computed type of a variable is the type of the
  3600                 // variable symbol, taken as a member of the site type.
  3601                 owntype = (sym.owner.kind == TYP &&
  3602                            sym.name != names._this && sym.name != names._super)
  3603                     ? types.memberType(site, sym)
  3604                     : sym.type;
  3606                 // If the variable is a constant, record constant value in
  3607                 // computed type.
  3608                 if (v.getConstValue() != null && isStaticReference(tree))
  3609                     owntype = owntype.constType(v.getConstValue());
  3611                 if (resultInfo.pkind == VAL) {
  3612                     owntype = capture(owntype); // capture "names as expressions"
  3614                 break;
  3615             case MTH: {
  3616                 owntype = checkMethod(site, sym,
  3617                         new ResultInfo(resultInfo.pkind, resultInfo.pt.getReturnType(), resultInfo.checkContext),
  3618                         env, TreeInfo.args(env.tree), resultInfo.pt.getParameterTypes(),
  3619                         resultInfo.pt.getTypeArguments());
  3620                 break;
  3622             case PCK: case ERR:
  3623                 owntype = sym.type;
  3624                 break;
  3625             default:
  3626                 throw new AssertionError("unexpected kind: " + sym.kind +
  3627                                          " in tree " + tree);
  3630             // Test (1): emit a `deprecation' warning if symbol is deprecated.
  3631             // (for constructors, the error was given when the constructor was
  3632             // resolved)
  3634             if (sym.name != names.init) {
  3635                 chk.checkDeprecated(tree.pos(), env.info.scope.owner, sym);
  3636                 chk.checkSunAPI(tree.pos(), sym);
  3637                 chk.checkProfile(tree.pos(), sym);
  3640             // Test (3): if symbol is a variable, check that its type and
  3641             // kind are compatible with the prototype and protokind.
  3642             return check(tree, owntype, sym.kind, resultInfo);
  3645         /** Check that variable is initialized and evaluate the variable's
  3646          *  initializer, if not yet done. Also check that variable is not
  3647          *  referenced before it is defined.
  3648          *  @param tree    The tree making up the variable reference.
  3649          *  @param env     The current environment.
  3650          *  @param v       The variable's symbol.
  3651          */
  3652         private void checkInit(JCTree tree,
  3653                                Env<AttrContext> env,
  3654                                VarSymbol v,
  3655                                boolean onlyWarning) {
  3656 //          System.err.println(v + " " + ((v.flags() & STATIC) != 0) + " " +
  3657 //                             tree.pos + " " + v.pos + " " +
  3658 //                             Resolve.isStatic(env));//DEBUG
  3660             // A forward reference is diagnosed if the declaration position
  3661             // of the variable is greater than the current tree position
  3662             // and the tree and variable definition occur in the same class
  3663             // definition.  Note that writes don't count as references.
  3664             // This check applies only to class and instance
  3665             // variables.  Local variables follow different scope rules,
  3666             // and are subject to definite assignment checking.
  3667             if ((env.info.enclVar == v || v.pos > tree.pos) &&
  3668                 v.owner.kind == TYP &&
  3669                 enclosingInitEnv(env) != null &&
  3670                 v.owner == env.info.scope.owner.enclClass() &&
  3671                 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env) &&
  3672                 (!env.tree.hasTag(ASSIGN) ||
  3673                  TreeInfo.skipParens(((JCAssign) env.tree).lhs) != tree)) {
  3674                 String suffix = (env.info.enclVar == v) ?
  3675                                 "self.ref" : "forward.ref";
  3676                 if (!onlyWarning || isStaticEnumField(v)) {
  3677                     log.error(tree.pos(), "illegal." + suffix);
  3678                 } else if (useBeforeDeclarationWarning) {
  3679                     log.warning(tree.pos(), suffix, v);
  3683             v.getConstValue(); // ensure initializer is evaluated
  3685             checkEnumInitializer(tree, env, v);
  3688         /**
  3689          * Returns the enclosing init environment associated with this env (if any). An init env
  3690          * can be either a field declaration env or a static/instance initializer env.
  3691          */
  3692         Env<AttrContext> enclosingInitEnv(Env<AttrContext> env) {
  3693             while (true) {
  3694                 switch (env.tree.getTag()) {
  3695                     case VARDEF:
  3696                         JCVariableDecl vdecl = (JCVariableDecl)env.tree;
  3697                         if (vdecl.sym.owner.kind == TYP) {
  3698                             //field
  3699                             return env;
  3701                         break;
  3702                     case BLOCK:
  3703                         if (env.next.tree.hasTag(CLASSDEF)) {
  3704                             //instance/static initializer
  3705                             return env;
  3707                         break;
  3708                     case METHODDEF:
  3709                     case CLASSDEF:
  3710                     case TOPLEVEL:
  3711                         return null;
  3713                 Assert.checkNonNull(env.next);
  3714                 env = env.next;
  3718         /**
  3719          * Check for illegal references to static members of enum.  In
  3720          * an enum type, constructors and initializers may not
  3721          * reference its static members unless they are constant.
  3723          * @param tree    The tree making up the variable reference.
  3724          * @param env     The current environment.
  3725          * @param v       The variable's symbol.
  3726          * @jls  section 8.9 Enums
  3727          */
  3728         private void checkEnumInitializer(JCTree tree, Env<AttrContext> env, VarSymbol v) {
  3729             // JLS:
  3730             //
  3731             // "It is a compile-time error to reference a static field
  3732             // of an enum type that is not a compile-time constant
  3733             // (15.28) from constructors, instance initializer blocks,
  3734             // or instance variable initializer expressions of that
  3735             // type. It is a compile-time error for the constructors,
  3736             // instance initializer blocks, or instance variable
  3737             // initializer expressions of an enum constant e to refer
  3738             // to itself or to an enum constant of the same type that
  3739             // is declared to the right of e."
  3740             if (isStaticEnumField(v)) {
  3741                 ClassSymbol enclClass = env.info.scope.owner.enclClass();
  3743                 if (enclClass == null || enclClass.owner == null)
  3744                     return;
  3746                 // See if the enclosing class is the enum (or a
  3747                 // subclass thereof) declaring v.  If not, this
  3748                 // reference is OK.
  3749                 if (v.owner != enclClass && !types.isSubtype(enclClass.type, v.owner.type))
  3750                     return;
  3752                 // If the reference isn't from an initializer, then
  3753                 // the reference is OK.
  3754                 if (!Resolve.isInitializer(env))
  3755                     return;
  3757                 log.error(tree.pos(), "illegal.enum.static.ref");
  3761         /** Is the given symbol a static, non-constant field of an Enum?
  3762          *  Note: enum literals should not be regarded as such
  3763          */
  3764         private boolean isStaticEnumField(VarSymbol v) {
  3765             return Flags.isEnum(v.owner) &&
  3766                    Flags.isStatic(v) &&
  3767                    !Flags.isConstant(v) &&
  3768                    v.name != names._class;
  3771     Warner noteWarner = new Warner();
  3773     /**
  3774      * Check that method arguments conform to its instantiation.
  3775      **/
  3776     public Type checkMethod(Type site,
  3777                             final Symbol sym,
  3778                             ResultInfo resultInfo,
  3779                             Env<AttrContext> env,
  3780                             final List<JCExpression> argtrees,
  3781                             List<Type> argtypes,
  3782                             List<Type> typeargtypes) {
  3783         // Test (5): if symbol is an instance method of a raw type, issue
  3784         // an unchecked warning if its argument types change under erasure.
  3785         if (allowGenerics &&
  3786             (sym.flags() & STATIC) == 0 &&
  3787             (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) {
  3788             Type s = types.asOuterSuper(site, sym.owner);
  3789             if (s != null && s.isRaw() &&
  3790                 !types.isSameTypes(sym.type.getParameterTypes(),
  3791                                    sym.erasure(types).getParameterTypes())) {
  3792                 chk.warnUnchecked(env.tree.pos(),
  3793                                   "unchecked.call.mbr.of.raw.type",
  3794                                   sym, s);
  3798         if (env.info.defaultSuperCallSite != null) {
  3799             for (Type sup : types.interfaces(env.enclClass.type).prepend(types.supertype((env.enclClass.type)))) {
  3800                 if (!sup.tsym.isSubClass(sym.enclClass(), types) ||
  3801                         types.isSameType(sup, env.info.defaultSuperCallSite)) continue;
  3802                 List<MethodSymbol> icand_sup =
  3803                         types.interfaceCandidates(sup, (MethodSymbol)sym);
  3804                 if (icand_sup.nonEmpty() &&
  3805                         icand_sup.head != sym &&
  3806                         icand_sup.head.overrides(sym, icand_sup.head.enclClass(), types, true)) {
  3807                     log.error(env.tree.pos(), "illegal.default.super.call", env.info.defaultSuperCallSite,
  3808                         diags.fragment("overridden.default", sym, sup));
  3809                     break;
  3812             env.info.defaultSuperCallSite = null;
  3815         if (sym.isStatic() && site.isInterface() && env.tree.hasTag(APPLY)) {
  3816             JCMethodInvocation app = (JCMethodInvocation)env.tree;
  3817             if (app.meth.hasTag(SELECT) &&
  3818                     !TreeInfo.isStaticSelector(((JCFieldAccess)app.meth).selected, names)) {
  3819                 log.error(env.tree.pos(), "illegal.static.intf.meth.call", site);
  3823         // Compute the identifier's instantiated type.
  3824         // For methods, we need to compute the instance type by
  3825         // Resolve.instantiate from the symbol's type as well as
  3826         // any type arguments and value arguments.
  3827         noteWarner.clear();
  3828         try {
  3829             Type owntype = rs.checkMethod(
  3830                     env,
  3831                     site,
  3832                     sym,
  3833                     resultInfo,
  3834                     argtypes,
  3835                     typeargtypes,
  3836                     noteWarner);
  3838             DeferredAttr.DeferredTypeMap checkDeferredMap =
  3839                 deferredAttr.new DeferredTypeMap(DeferredAttr.AttrMode.CHECK, sym, env.info.pendingResolutionPhase);
  3841             argtypes = Type.map(argtypes, checkDeferredMap);
  3843             if (noteWarner.hasNonSilentLint(LintCategory.UNCHECKED)) {
  3844                 chk.warnUnchecked(env.tree.pos(),
  3845                         "unchecked.meth.invocation.applied",
  3846                         kindName(sym),
  3847                         sym.name,
  3848                         rs.methodArguments(sym.type.getParameterTypes()),
  3849                         rs.methodArguments(Type.map(argtypes, checkDeferredMap)),
  3850                         kindName(sym.location()),
  3851                         sym.location());
  3852                owntype = new MethodType(owntype.getParameterTypes(),
  3853                        types.erasure(owntype.getReturnType()),
  3854                        types.erasure(owntype.getThrownTypes()),
  3855                        syms.methodClass);
  3858             return chk.checkMethod(owntype, sym, env, argtrees, argtypes, env.info.lastResolveVarargs(),
  3859                     resultInfo.checkContext.inferenceContext());
  3860         } catch (Infer.InferenceException ex) {
  3861             //invalid target type - propagate exception outwards or report error
  3862             //depending on the current check context
  3863             resultInfo.checkContext.report(env.tree.pos(), ex.getDiagnostic());
  3864             return types.createErrorType(site);
  3865         } catch (Resolve.InapplicableMethodException ex) {
  3866             final JCDiagnostic diag = ex.getDiagnostic();
  3867             Resolve.InapplicableSymbolError errSym = rs.new InapplicableSymbolError(null) {
  3868                 @Override
  3869                 protected Pair<Symbol, JCDiagnostic> errCandidate() {
  3870                     return new Pair<Symbol, JCDiagnostic>(sym, diag);
  3872             };
  3873             List<Type> argtypes2 = Type.map(argtypes,
  3874                     rs.new ResolveDeferredRecoveryMap(AttrMode.CHECK, sym, env.info.pendingResolutionPhase));
  3875             JCDiagnostic errDiag = errSym.getDiagnostic(JCDiagnostic.DiagnosticType.ERROR,
  3876                     env.tree, sym, site, sym.name, argtypes2, typeargtypes);
  3877             log.report(errDiag);
  3878             return types.createErrorType(site);
  3882     public void visitLiteral(JCLiteral tree) {
  3883         result = check(
  3884             tree, litType(tree.typetag).constType(tree.value), VAL, resultInfo);
  3886     //where
  3887     /** Return the type of a literal with given type tag.
  3888      */
  3889     Type litType(TypeTag tag) {
  3890         return (tag == CLASS) ? syms.stringType : syms.typeOfTag[tag.ordinal()];
  3893     public void visitTypeIdent(JCPrimitiveTypeTree tree) {
  3894         result = check(tree, syms.typeOfTag[tree.typetag.ordinal()], TYP, resultInfo);
  3897     public void visitTypeArray(JCArrayTypeTree tree) {
  3898         Type etype = attribType(tree.elemtype, env);
  3899         Type type = new ArrayType(etype, syms.arrayClass);
  3900         result = check(tree, type, TYP, resultInfo);
  3903     /** Visitor method for parameterized types.
  3904      *  Bound checking is left until later, since types are attributed
  3905      *  before supertype structure is completely known
  3906      */
  3907     public void visitTypeApply(JCTypeApply tree) {
  3908         Type owntype = types.createErrorType(tree.type);
  3910         // Attribute functor part of application and make sure it's a class.
  3911         Type clazztype = chk.checkClassType(tree.clazz.pos(), attribType(tree.clazz, env));
  3913         // Attribute type parameters
  3914         List<Type> actuals = attribTypes(tree.arguments, env);
  3916         if (clazztype.hasTag(CLASS)) {
  3917             List<Type> formals = clazztype.tsym.type.getTypeArguments();
  3918             if (actuals.isEmpty()) //diamond
  3919                 actuals = formals;
  3921             if (actuals.length() == formals.length()) {
  3922                 List<Type> a = actuals;
  3923                 List<Type> f = formals;
  3924                 while (a.nonEmpty()) {
  3925                     a.head = a.head.withTypeVar(f.head);
  3926                     a = a.tail;
  3927                     f = f.tail;
  3929                 // Compute the proper generic outer
  3930                 Type clazzOuter = clazztype.getEnclosingType();
  3931                 if (clazzOuter.hasTag(CLASS)) {
  3932                     Type site;
  3933                     JCExpression clazz = TreeInfo.typeIn(tree.clazz);
  3934                     if (clazz.hasTag(IDENT)) {
  3935                         site = env.enclClass.sym.type;
  3936                     } else if (clazz.hasTag(SELECT)) {
  3937                         site = ((JCFieldAccess) clazz).selected.type;
  3938                     } else throw new AssertionError(""+tree);
  3939                     if (clazzOuter.hasTag(CLASS) && site != clazzOuter) {
  3940                         if (site.hasTag(CLASS))
  3941                             site = types.asOuterSuper(site, clazzOuter.tsym);
  3942                         if (site == null)
  3943                             site = types.erasure(clazzOuter);
  3944                         clazzOuter = site;
  3947                 owntype = new ClassType(clazzOuter, actuals, clazztype.tsym);
  3948             } else {
  3949                 if (formals.length() != 0) {
  3950                     log.error(tree.pos(), "wrong.number.type.args",
  3951                               Integer.toString(formals.length()));
  3952                 } else {
  3953                     log.error(tree.pos(), "type.doesnt.take.params", clazztype.tsym);
  3955                 owntype = types.createErrorType(tree.type);
  3958         result = check(tree, owntype, TYP, resultInfo);
  3961     public void visitTypeUnion(JCTypeUnion tree) {
  3962         ListBuffer<Type> multicatchTypes = new ListBuffer<>();
  3963         ListBuffer<Type> all_multicatchTypes = null; // lazy, only if needed
  3964         for (JCExpression typeTree : tree.alternatives) {
  3965             Type ctype = attribType(typeTree, env);
  3966             ctype = chk.checkType(typeTree.pos(),
  3967                           chk.checkClassType(typeTree.pos(), ctype),
  3968                           syms.throwableType);
  3969             if (!ctype.isErroneous()) {
  3970                 //check that alternatives of a union type are pairwise
  3971                 //unrelated w.r.t. subtyping
  3972                 if (chk.intersects(ctype,  multicatchTypes.toList())) {
  3973                     for (Type t : multicatchTypes) {
  3974                         boolean sub = types.isSubtype(ctype, t);
  3975                         boolean sup = types.isSubtype(t, ctype);
  3976                         if (sub || sup) {
  3977                             //assume 'a' <: 'b'
  3978                             Type a = sub ? ctype : t;
  3979                             Type b = sub ? t : ctype;
  3980                             log.error(typeTree.pos(), "multicatch.types.must.be.disjoint", a, b);
  3984                 multicatchTypes.append(ctype);
  3985                 if (all_multicatchTypes != null)
  3986                     all_multicatchTypes.append(ctype);
  3987             } else {
  3988                 if (all_multicatchTypes == null) {
  3989                     all_multicatchTypes = new ListBuffer<>();
  3990                     all_multicatchTypes.appendList(multicatchTypes);
  3992                 all_multicatchTypes.append(ctype);
  3995         Type t = check(noCheckTree, types.lub(multicatchTypes.toList()), TYP, resultInfo);
  3996         if (t.hasTag(CLASS)) {
  3997             List<Type> alternatives =
  3998                 ((all_multicatchTypes == null) ? multicatchTypes : all_multicatchTypes).toList();
  3999             t = new UnionClassType((ClassType) t, alternatives);
  4001         tree.type = result = t;
  4004     public void visitTypeIntersection(JCTypeIntersection tree) {
  4005         attribTypes(tree.bounds, env);
  4006         tree.type = result = checkIntersection(tree, tree.bounds);
  4009     public void visitTypeParameter(JCTypeParameter tree) {
  4010         TypeVar typeVar = (TypeVar) tree.type;
  4012         if (tree.annotations != null && tree.annotations.nonEmpty()) {
  4013             annotateType(tree, tree.annotations);
  4016         if (!typeVar.bound.isErroneous()) {
  4017             //fixup type-parameter bound computed in 'attribTypeVariables'
  4018             typeVar.bound = checkIntersection(tree, tree.bounds);
  4022     Type checkIntersection(JCTree tree, List<JCExpression> bounds) {
  4023         Set<Type> boundSet = new HashSet<Type>();
  4024         if (bounds.nonEmpty()) {
  4025             // accept class or interface or typevar as first bound.
  4026             bounds.head.type = checkBase(bounds.head.type, bounds.head, env, false, false, false);
  4027             boundSet.add(types.erasure(bounds.head.type));
  4028             if (bounds.head.type.isErroneous()) {
  4029                 return bounds.head.type;
  4031             else if (bounds.head.type.hasTag(TYPEVAR)) {
  4032                 // if first bound was a typevar, do not accept further bounds.
  4033                 if (bounds.tail.nonEmpty()) {
  4034                     log.error(bounds.tail.head.pos(),
  4035                               "type.var.may.not.be.followed.by.other.bounds");
  4036                     return bounds.head.type;
  4038             } else {
  4039                 // if first bound was a class or interface, accept only interfaces
  4040                 // as further bounds.
  4041                 for (JCExpression bound : bounds.tail) {
  4042                     bound.type = checkBase(bound.type, bound, env, false, true, false);
  4043                     if (bound.type.isErroneous()) {
  4044                         bounds = List.of(bound);
  4046                     else if (bound.type.hasTag(CLASS)) {
  4047                         chk.checkNotRepeated(bound.pos(), types.erasure(bound.type), boundSet);
  4053         if (bounds.length() == 0) {
  4054             return syms.objectType;
  4055         } else if (bounds.length() == 1) {
  4056             return bounds.head.type;
  4057         } else {
  4058             Type owntype = types.makeIntersectionType(TreeInfo.types(bounds));
  4059             // ... the variable's bound is a class type flagged COMPOUND
  4060             // (see comment for TypeVar.bound).
  4061             // In this case, generate a class tree that represents the
  4062             // bound class, ...
  4063             JCExpression extending;
  4064             List<JCExpression> implementing;
  4065             if (!bounds.head.type.isInterface()) {
  4066                 extending = bounds.head;
  4067                 implementing = bounds.tail;
  4068             } else {
  4069                 extending = null;
  4070                 implementing = bounds;
  4072             JCClassDecl cd = make.at(tree).ClassDef(
  4073                 make.Modifiers(PUBLIC | ABSTRACT),
  4074                 names.empty, List.<JCTypeParameter>nil(),
  4075                 extending, implementing, List.<JCTree>nil());
  4077             ClassSymbol c = (ClassSymbol)owntype.tsym;
  4078             Assert.check((c.flags() & COMPOUND) != 0);
  4079             cd.sym = c;
  4080             c.sourcefile = env.toplevel.sourcefile;
  4082             // ... and attribute the bound class
  4083             c.flags_field |= UNATTRIBUTED;
  4084             Env<AttrContext> cenv = enter.classEnv(cd, env);
  4085             typeEnvs.put(c, cenv);
  4086             attribClass(c);
  4087             return owntype;
  4091     public void visitWildcard(JCWildcard tree) {
  4092         //- System.err.println("visitWildcard("+tree+");");//DEBUG
  4093         Type type = (tree.kind.kind == BoundKind.UNBOUND)
  4094             ? syms.objectType
  4095             : attribType(tree.inner, env);
  4096         result = check(tree, new WildcardType(chk.checkRefType(tree.pos(), type),
  4097                                               tree.kind.kind,
  4098                                               syms.boundClass),
  4099                        TYP, resultInfo);
  4102     public void visitAnnotation(JCAnnotation tree) {
  4103         Assert.error("should be handled in Annotate");
  4106     public void visitAnnotatedType(JCAnnotatedType tree) {
  4107         Type underlyingType = attribType(tree.getUnderlyingType(), env);
  4108         this.attribAnnotationTypes(tree.annotations, env);
  4109         annotateType(tree, tree.annotations);
  4110         result = tree.type = underlyingType;
  4113     /**
  4114      * Apply the annotations to the particular type.
  4115      */
  4116     public void annotateType(final JCTree tree, final List<JCAnnotation> annotations) {
  4117         annotate.typeAnnotation(new Annotate.Worker() {
  4118             @Override
  4119             public String toString() {
  4120                 return "annotate " + annotations + " onto " + tree;
  4122             @Override
  4123             public void run() {
  4124                 List<Attribute.TypeCompound> compounds = fromAnnotations(annotations);
  4125                 if (annotations.size() == compounds.size()) {
  4126                     // All annotations were successfully converted into compounds
  4127                     tree.type = tree.type.unannotatedType().annotatedType(compounds);
  4130         });
  4133     private static List<Attribute.TypeCompound> fromAnnotations(List<JCAnnotation> annotations) {
  4134         if (annotations.isEmpty()) {
  4135             return List.nil();
  4138         ListBuffer<Attribute.TypeCompound> buf = new ListBuffer<>();
  4139         for (JCAnnotation anno : annotations) {
  4140             if (anno.attribute != null) {
  4141                 // TODO: this null-check is only needed for an obscure
  4142                 // ordering issue, where annotate.flush is called when
  4143                 // the attribute is not set yet. For an example failure
  4144                 // try the referenceinfos/NestedTypes.java test.
  4145                 // Any better solutions?
  4146                 buf.append((Attribute.TypeCompound) anno.attribute);
  4148             // Eventually we will want to throw an exception here, but
  4149             // we can't do that just yet, because it gets triggered
  4150             // when attempting to attach an annotation that isn't
  4151             // defined.
  4153         return buf.toList();
  4156     public void visitErroneous(JCErroneous tree) {
  4157         if (tree.errs != null)
  4158             for (JCTree err : tree.errs)
  4159                 attribTree(err, env, new ResultInfo(ERR, pt()));
  4160         result = tree.type = syms.errType;
  4163     /** Default visitor method for all other trees.
  4164      */
  4165     public void visitTree(JCTree tree) {
  4166         throw new AssertionError();
  4169     /**
  4170      * Attribute an env for either a top level tree or class declaration.
  4171      */
  4172     public void attrib(Env<AttrContext> env) {
  4173         if (env.tree.hasTag(TOPLEVEL))
  4174             attribTopLevel(env);
  4175         else
  4176             attribClass(env.tree.pos(), env.enclClass.sym);
  4179     /**
  4180      * Attribute a top level tree. These trees are encountered when the
  4181      * package declaration has annotations.
  4182      */
  4183     public void attribTopLevel(Env<AttrContext> env) {
  4184         JCCompilationUnit toplevel = env.toplevel;
  4185         try {
  4186             annotate.flush();
  4187         } catch (CompletionFailure ex) {
  4188             chk.completionError(toplevel.pos(), ex);
  4192     /** Main method: attribute class definition associated with given class symbol.
  4193      *  reporting completion failures at the given position.
  4194      *  @param pos The source position at which completion errors are to be
  4195      *             reported.
  4196      *  @param c   The class symbol whose definition will be attributed.
  4197      */
  4198     public void attribClass(DiagnosticPosition pos, ClassSymbol c) {
  4199         try {
  4200             annotate.flush();
  4201             attribClass(c);
  4202         } catch (CompletionFailure ex) {
  4203             chk.completionError(pos, ex);
  4207     /** Attribute class definition associated with given class symbol.
  4208      *  @param c   The class symbol whose definition will be attributed.
  4209      */
  4210     void attribClass(ClassSymbol c) throws CompletionFailure {
  4211         if (c.type.hasTag(ERROR)) return;
  4213         // Check for cycles in the inheritance graph, which can arise from
  4214         // ill-formed class files.
  4215         chk.checkNonCyclic(null, c.type);
  4217         Type st = types.supertype(c.type);
  4218         if ((c.flags_field & Flags.COMPOUND) == 0) {
  4219             // First, attribute superclass.
  4220             if (st.hasTag(CLASS))
  4221                 attribClass((ClassSymbol)st.tsym);
  4223             // Next attribute owner, if it is a class.
  4224             if (c.owner.kind == TYP && c.owner.type.hasTag(CLASS))
  4225                 attribClass((ClassSymbol)c.owner);
  4228         // The previous operations might have attributed the current class
  4229         // if there was a cycle. So we test first whether the class is still
  4230         // UNATTRIBUTED.
  4231         if ((c.flags_field & UNATTRIBUTED) != 0) {
  4232             c.flags_field &= ~UNATTRIBUTED;
  4234             // Get environment current at the point of class definition.
  4235             Env<AttrContext> env = typeEnvs.get(c);
  4237             // The info.lint field in the envs stored in typeEnvs is deliberately uninitialized,
  4238             // because the annotations were not available at the time the env was created. Therefore,
  4239             // we look up the environment chain for the first enclosing environment for which the
  4240             // lint value is set. Typically, this is the parent env, but might be further if there
  4241             // are any envs created as a result of TypeParameter nodes.
  4242             Env<AttrContext> lintEnv = env;
  4243             while (lintEnv.info.lint == null)
  4244                 lintEnv = lintEnv.next;
  4246             // Having found the enclosing lint value, we can initialize the lint value for this class
  4247             env.info.lint = lintEnv.info.lint.augment(c);
  4249             Lint prevLint = chk.setLint(env.info.lint);
  4250             JavaFileObject prev = log.useSource(c.sourcefile);
  4251             ResultInfo prevReturnRes = env.info.returnResult;
  4253             try {
  4254                 deferredLintHandler.flush(env.tree);
  4255                 env.info.returnResult = null;
  4256                 // java.lang.Enum may not be subclassed by a non-enum
  4257                 if (st.tsym == syms.enumSym &&
  4258                     ((c.flags_field & (Flags.ENUM|Flags.COMPOUND)) == 0))
  4259                     log.error(env.tree.pos(), "enum.no.subclassing");
  4261                 // Enums may not be extended by source-level classes
  4262                 if (st.tsym != null &&
  4263                     ((st.tsym.flags_field & Flags.ENUM) != 0) &&
  4264                     ((c.flags_field & (Flags.ENUM | Flags.COMPOUND)) == 0)) {
  4265                     log.error(env.tree.pos(), "enum.types.not.extensible");
  4268                 if (isSerializable(c.type)) {
  4269                     env.info.isSerializable = true;
  4272                 attribClassBody(env, c);
  4274                 chk.checkDeprecatedAnnotation(env.tree.pos(), c);
  4275                 chk.checkClassOverrideEqualsAndHashIfNeeded(env.tree.pos(), c);
  4276                 chk.checkFunctionalInterface((JCClassDecl) env.tree, c);
  4277             } finally {
  4278                 env.info.returnResult = prevReturnRes;
  4279                 log.useSource(prev);
  4280                 chk.setLint(prevLint);
  4286     public void visitImport(JCImport tree) {
  4287         // nothing to do
  4290     /** Finish the attribution of a class. */
  4291     private void attribClassBody(Env<AttrContext> env, ClassSymbol c) {
  4292         JCClassDecl tree = (JCClassDecl)env.tree;
  4293         Assert.check(c == tree.sym);
  4295         // Validate type parameters, supertype and interfaces.
  4296         attribStats(tree.typarams, env);
  4297         if (!c.isAnonymous()) {
  4298             //already checked if anonymous
  4299             chk.validate(tree.typarams, env);
  4300             chk.validate(tree.extending, env);
  4301             chk.validate(tree.implementing, env);
  4304         c.markAbstractIfNeeded(types);
  4306         // If this is a non-abstract class, check that it has no abstract
  4307         // methods or unimplemented methods of an implemented interface.
  4308         if ((c.flags() & (ABSTRACT | INTERFACE)) == 0) {
  4309             if (!relax)
  4310                 chk.checkAllDefined(tree.pos(), c);
  4313         if ((c.flags() & ANNOTATION) != 0) {
  4314             if (tree.implementing.nonEmpty())
  4315                 log.error(tree.implementing.head.pos(),
  4316                           "cant.extend.intf.annotation");
  4317             if (tree.typarams.nonEmpty())
  4318                 log.error(tree.typarams.head.pos(),
  4319                           "intf.annotation.cant.have.type.params");
  4321             // If this annotation has a @Repeatable, validate
  4322             Attribute.Compound repeatable = c.attribute(syms.repeatableType.tsym);
  4323             if (repeatable != null) {
  4324                 // get diagnostic position for error reporting
  4325                 DiagnosticPosition cbPos = getDiagnosticPosition(tree, repeatable.type);
  4326                 Assert.checkNonNull(cbPos);
  4328                 chk.validateRepeatable(c, repeatable, cbPos);
  4330         } else {
  4331             // Check that all extended classes and interfaces
  4332             // are compatible (i.e. no two define methods with same arguments
  4333             // yet different return types).  (JLS 8.4.6.3)
  4334             chk.checkCompatibleSupertypes(tree.pos(), c.type);
  4335             if (allowDefaultMethods) {
  4336                 chk.checkDefaultMethodClashes(tree.pos(), c.type);
  4340         // Check that class does not import the same parameterized interface
  4341         // with two different argument lists.
  4342         chk.checkClassBounds(tree.pos(), c.type);
  4344         tree.type = c.type;
  4346         for (List<JCTypeParameter> l = tree.typarams;
  4347              l.nonEmpty(); l = l.tail) {
  4348              Assert.checkNonNull(env.info.scope.lookup(l.head.name).scope);
  4351         // Check that a generic class doesn't extend Throwable
  4352         if (!c.type.allparams().isEmpty() && types.isSubtype(c.type, syms.throwableType))
  4353             log.error(tree.extending.pos(), "generic.throwable");
  4355         // Check that all methods which implement some
  4356         // method conform to the method they implement.
  4357         chk.checkImplementations(tree);
  4359         //check that a resource implementing AutoCloseable cannot throw InterruptedException
  4360         checkAutoCloseable(tree.pos(), env, c.type);
  4362         for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
  4363             // Attribute declaration
  4364             attribStat(l.head, env);
  4365             // Check that declarations in inner classes are not static (JLS 8.1.2)
  4366             // Make an exception for static constants.
  4367             if (c.owner.kind != PCK &&
  4368                 ((c.flags() & STATIC) == 0 || c.name == names.empty) &&
  4369                 (TreeInfo.flags(l.head) & (STATIC | INTERFACE)) != 0) {
  4370                 Symbol sym = null;
  4371                 if (l.head.hasTag(VARDEF)) sym = ((JCVariableDecl) l.head).sym;
  4372                 if (sym == null ||
  4373                     sym.kind != VAR ||
  4374                     ((VarSymbol) sym).getConstValue() == null)
  4375                     log.error(l.head.pos(), "icls.cant.have.static.decl", c);
  4379         // Check for cycles among non-initial constructors.
  4380         chk.checkCyclicConstructors(tree);
  4382         // Check for cycles among annotation elements.
  4383         chk.checkNonCyclicElements(tree);
  4385         // Check for proper use of serialVersionUID
  4386         if (env.info.lint.isEnabled(LintCategory.SERIAL) &&
  4387             isSerializable(c.type) &&
  4388             (c.flags() & Flags.ENUM) == 0 &&
  4389             checkForSerial(c)) {
  4390             checkSerialVersionUID(tree, c);
  4392         if (allowTypeAnnos) {
  4393             // Correctly organize the postions of the type annotations
  4394             typeAnnotations.organizeTypeAnnotationsBodies(tree);
  4396             // Check type annotations applicability rules
  4397             validateTypeAnnotations(tree, false);
  4400         // where
  4401         boolean checkForSerial(ClassSymbol c) {
  4402             if ((c.flags() & ABSTRACT) == 0) {
  4403                 return true;
  4404             } else {
  4405                 return c.members().anyMatch(anyNonAbstractOrDefaultMethod);
  4409         public static final Filter<Symbol> anyNonAbstractOrDefaultMethod = new Filter<Symbol>() {
  4410             @Override
  4411             public boolean accepts(Symbol s) {
  4412                 return s.kind == Kinds.MTH &&
  4413                        (s.flags() & (DEFAULT | ABSTRACT)) != ABSTRACT;
  4415         };
  4417         /** get a diagnostic position for an attribute of Type t, or null if attribute missing */
  4418         private DiagnosticPosition getDiagnosticPosition(JCClassDecl tree, Type t) {
  4419             for(List<JCAnnotation> al = tree.mods.annotations; !al.isEmpty(); al = al.tail) {
  4420                 if (types.isSameType(al.head.annotationType.type, t))
  4421                     return al.head.pos();
  4424             return null;
  4427         /** check if a type is a subtype of Serializable, if that is available. */
  4428         boolean isSerializable(Type t) {
  4429             try {
  4430                 syms.serializableType.complete();
  4432             catch (CompletionFailure e) {
  4433                 return false;
  4435             return types.isSubtype(t, syms.serializableType);
  4438         /** Check that an appropriate serialVersionUID member is defined. */
  4439         private void checkSerialVersionUID(JCClassDecl tree, ClassSymbol c) {
  4441             // check for presence of serialVersionUID
  4442             Scope.Entry e = c.members().lookup(names.serialVersionUID);
  4443             while (e.scope != null && e.sym.kind != VAR) e = e.next();
  4444             if (e.scope == null) {
  4445                 log.warning(LintCategory.SERIAL,
  4446                         tree.pos(), "missing.SVUID", c);
  4447                 return;
  4450             // check that it is static final
  4451             VarSymbol svuid = (VarSymbol)e.sym;
  4452             if ((svuid.flags() & (STATIC | FINAL)) !=
  4453                 (STATIC | FINAL))
  4454                 log.warning(LintCategory.SERIAL,
  4455                         TreeInfo.diagnosticPositionFor(svuid, tree), "improper.SVUID", c);
  4457             // check that it is long
  4458             else if (!svuid.type.hasTag(LONG))
  4459                 log.warning(LintCategory.SERIAL,
  4460                         TreeInfo.diagnosticPositionFor(svuid, tree), "long.SVUID", c);
  4462             // check constant
  4463             else if (svuid.getConstValue() == null)
  4464                 log.warning(LintCategory.SERIAL,
  4465                         TreeInfo.diagnosticPositionFor(svuid, tree), "constant.SVUID", c);
  4468     private Type capture(Type type) {
  4469         return types.capture(type);
  4472     public void validateTypeAnnotations(JCTree tree, boolean sigOnly) {
  4473         tree.accept(new TypeAnnotationsValidator(sigOnly));
  4475     //where
  4476     private final class TypeAnnotationsValidator extends TreeScanner {
  4478         private final boolean sigOnly;
  4479         public TypeAnnotationsValidator(boolean sigOnly) {
  4480             this.sigOnly = sigOnly;
  4483         public void visitAnnotation(JCAnnotation tree) {
  4484             chk.validateTypeAnnotation(tree, false);
  4485             super.visitAnnotation(tree);
  4487         public void visitAnnotatedType(JCAnnotatedType tree) {
  4488             if (!tree.underlyingType.type.isErroneous()) {
  4489                 super.visitAnnotatedType(tree);
  4492         public void visitTypeParameter(JCTypeParameter tree) {
  4493             chk.validateTypeAnnotations(tree.annotations, true);
  4494             scan(tree.bounds);
  4495             // Don't call super.
  4496             // This is needed because above we call validateTypeAnnotation with
  4497             // false, which would forbid annotations on type parameters.
  4498             // super.visitTypeParameter(tree);
  4500         public void visitMethodDef(JCMethodDecl tree) {
  4501             if (tree.recvparam != null &&
  4502                     !tree.recvparam.vartype.type.isErroneous()) {
  4503                 checkForDeclarationAnnotations(tree.recvparam.mods.annotations,
  4504                         tree.recvparam.vartype.type.tsym);
  4506             if (tree.restype != null && tree.restype.type != null) {
  4507                 validateAnnotatedType(tree.restype, tree.restype.type);
  4509             if (sigOnly) {
  4510                 scan(tree.mods);
  4511                 scan(tree.restype);
  4512                 scan(tree.typarams);
  4513                 scan(tree.recvparam);
  4514                 scan(tree.params);
  4515                 scan(tree.thrown);
  4516             } else {
  4517                 scan(tree.defaultValue);
  4518                 scan(tree.body);
  4521         public void visitVarDef(final JCVariableDecl tree) {
  4522             if (tree.sym != null && tree.sym.type != null)
  4523                 validateAnnotatedType(tree.vartype, tree.sym.type);
  4524             scan(tree.mods);
  4525             scan(tree.vartype);
  4526             if (!sigOnly) {
  4527                 scan(tree.init);
  4530         public void visitTypeCast(JCTypeCast tree) {
  4531             if (tree.clazz != null && tree.clazz.type != null)
  4532                 validateAnnotatedType(tree.clazz, tree.clazz.type);
  4533             super.visitTypeCast(tree);
  4535         public void visitTypeTest(JCInstanceOf tree) {
  4536             if (tree.clazz != null && tree.clazz.type != null)
  4537                 validateAnnotatedType(tree.clazz, tree.clazz.type);
  4538             super.visitTypeTest(tree);
  4540         public void visitNewClass(JCNewClass tree) {
  4541             if (tree.clazz != null && tree.clazz.type != null) {
  4542                 if (tree.clazz.hasTag(ANNOTATED_TYPE)) {
  4543                     checkForDeclarationAnnotations(((JCAnnotatedType) tree.clazz).annotations,
  4544                             tree.clazz.type.tsym);
  4546                 if (tree.def != null) {
  4547                     checkForDeclarationAnnotations(tree.def.mods.annotations, tree.clazz.type.tsym);
  4550                 validateAnnotatedType(tree.clazz, tree.clazz.type);
  4552             super.visitNewClass(tree);
  4554         public void visitNewArray(JCNewArray tree) {
  4555             if (tree.elemtype != null && tree.elemtype.type != null) {
  4556                 if (tree.elemtype.hasTag(ANNOTATED_TYPE)) {
  4557                     checkForDeclarationAnnotations(((JCAnnotatedType) tree.elemtype).annotations,
  4558                             tree.elemtype.type.tsym);
  4560                 validateAnnotatedType(tree.elemtype, tree.elemtype.type);
  4562             super.visitNewArray(tree);
  4564         public void visitClassDef(JCClassDecl tree) {
  4565             if (sigOnly) {
  4566                 scan(tree.mods);
  4567                 scan(tree.typarams);
  4568                 scan(tree.extending);
  4569                 scan(tree.implementing);
  4571             for (JCTree member : tree.defs) {
  4572                 if (member.hasTag(Tag.CLASSDEF)) {
  4573                     continue;
  4575                 scan(member);
  4578         public void visitBlock(JCBlock tree) {
  4579             if (!sigOnly) {
  4580                 scan(tree.stats);
  4584         /* I would want to model this after
  4585          * com.sun.tools.javac.comp.Check.Validator.visitSelectInternal(JCFieldAccess)
  4586          * and override visitSelect and visitTypeApply.
  4587          * However, we only set the annotated type in the top-level type
  4588          * of the symbol.
  4589          * Therefore, we need to override each individual location where a type
  4590          * can occur.
  4591          */
  4592         private void validateAnnotatedType(final JCTree errtree, final Type type) {
  4593             // System.out.println("Attr.validateAnnotatedType: " + errtree + " type: " + type);
  4595             if (type.isPrimitiveOrVoid()) {
  4596                 return;
  4599             JCTree enclTr = errtree;
  4600             Type enclTy = type;
  4602             boolean repeat = true;
  4603             while (repeat) {
  4604                 if (enclTr.hasTag(TYPEAPPLY)) {
  4605                     List<Type> tyargs = enclTy.getTypeArguments();
  4606                     List<JCExpression> trargs = ((JCTypeApply)enclTr).getTypeArguments();
  4607                     if (trargs.length() > 0) {
  4608                         // Nothing to do for diamonds
  4609                         if (tyargs.length() == trargs.length()) {
  4610                             for (int i = 0; i < tyargs.length(); ++i) {
  4611                                 validateAnnotatedType(trargs.get(i), tyargs.get(i));
  4614                         // If the lengths don't match, it's either a diamond
  4615                         // or some nested type that redundantly provides
  4616                         // type arguments in the tree.
  4619                     // Look at the clazz part of a generic type
  4620                     enclTr = ((JCTree.JCTypeApply)enclTr).clazz;
  4623                 if (enclTr.hasTag(SELECT)) {
  4624                     enclTr = ((JCTree.JCFieldAccess)enclTr).getExpression();
  4625                     if (enclTy != null &&
  4626                             !enclTy.hasTag(NONE)) {
  4627                         enclTy = enclTy.getEnclosingType();
  4629                 } else if (enclTr.hasTag(ANNOTATED_TYPE)) {
  4630                     JCAnnotatedType at = (JCTree.JCAnnotatedType) enclTr;
  4631                     if (enclTy == null ||
  4632                             enclTy.hasTag(NONE)) {
  4633                         if (at.getAnnotations().size() == 1) {
  4634                             log.error(at.underlyingType.pos(), "cant.type.annotate.scoping.1", at.getAnnotations().head.attribute);
  4635                         } else {
  4636                             ListBuffer<Attribute.Compound> comps = new ListBuffer<Attribute.Compound>();
  4637                             for (JCAnnotation an : at.getAnnotations()) {
  4638                                 comps.add(an.attribute);
  4640                             log.error(at.underlyingType.pos(), "cant.type.annotate.scoping", comps.toList());
  4642                         repeat = false;
  4644                     enclTr = at.underlyingType;
  4645                     // enclTy doesn't need to be changed
  4646                 } else if (enclTr.hasTag(IDENT)) {
  4647                     repeat = false;
  4648                 } else if (enclTr.hasTag(JCTree.Tag.WILDCARD)) {
  4649                     JCWildcard wc = (JCWildcard) enclTr;
  4650                     if (wc.getKind() == JCTree.Kind.EXTENDS_WILDCARD) {
  4651                         validateAnnotatedType(wc.getBound(), ((WildcardType)enclTy.unannotatedType()).getExtendsBound());
  4652                     } else if (wc.getKind() == JCTree.Kind.SUPER_WILDCARD) {
  4653                         validateAnnotatedType(wc.getBound(), ((WildcardType)enclTy.unannotatedType()).getSuperBound());
  4654                     } else {
  4655                         // Nothing to do for UNBOUND
  4657                     repeat = false;
  4658                 } else if (enclTr.hasTag(TYPEARRAY)) {
  4659                     JCArrayTypeTree art = (JCArrayTypeTree) enclTr;
  4660                     validateAnnotatedType(art.getType(), ((ArrayType)enclTy.unannotatedType()).getComponentType());
  4661                     repeat = false;
  4662                 } else if (enclTr.hasTag(TYPEUNION)) {
  4663                     JCTypeUnion ut = (JCTypeUnion) enclTr;
  4664                     for (JCTree t : ut.getTypeAlternatives()) {
  4665                         validateAnnotatedType(t, t.type);
  4667                     repeat = false;
  4668                 } else if (enclTr.hasTag(TYPEINTERSECTION)) {
  4669                     JCTypeIntersection it = (JCTypeIntersection) enclTr;
  4670                     for (JCTree t : it.getBounds()) {
  4671                         validateAnnotatedType(t, t.type);
  4673                     repeat = false;
  4674                 } else if (enclTr.getKind() == JCTree.Kind.PRIMITIVE_TYPE ||
  4675                            enclTr.getKind() == JCTree.Kind.ERRONEOUS) {
  4676                     repeat = false;
  4677                 } else {
  4678                     Assert.error("Unexpected tree: " + enclTr + " with kind: " + enclTr.getKind() +
  4679                             " within: "+ errtree + " with kind: " + errtree.getKind());
  4684         private void checkForDeclarationAnnotations(List<? extends JCAnnotation> annotations,
  4685                 Symbol sym) {
  4686             // Ensure that no declaration annotations are present.
  4687             // Note that a tree type might be an AnnotatedType with
  4688             // empty annotations, if only declaration annotations were given.
  4689             // This method will raise an error for such a type.
  4690             for (JCAnnotation ai : annotations) {
  4691                 if (!ai.type.isErroneous() &&
  4692                         typeAnnotations.annotationType(ai.attribute, sym) == TypeAnnotations.AnnotationType.DECLARATION) {
  4693                     log.error(ai.pos(), "annotation.type.not.applicable");
  4697     };
  4699     // <editor-fold desc="post-attribution visitor">
  4701     /**
  4702      * Handle missing types/symbols in an AST. This routine is useful when
  4703      * the compiler has encountered some errors (which might have ended up
  4704      * terminating attribution abruptly); if the compiler is used in fail-over
  4705      * mode (e.g. by an IDE) and the AST contains semantic errors, this routine
  4706      * prevents NPE to be progagated during subsequent compilation steps.
  4707      */
  4708     public void postAttr(JCTree tree) {
  4709         new PostAttrAnalyzer().scan(tree);
  4712     class PostAttrAnalyzer extends TreeScanner {
  4714         private void initTypeIfNeeded(JCTree that) {
  4715             if (that.type == null) {
  4716                 if (that.hasTag(METHODDEF)) {
  4717                     that.type = dummyMethodType((JCMethodDecl)that);
  4718                 } else {
  4719                     that.type = syms.unknownType;
  4724         /* Construct a dummy method type. If we have a method declaration,
  4725          * and the declared return type is void, then use that return type
  4726          * instead of UNKNOWN to avoid spurious error messages in lambda
  4727          * bodies (see:JDK-8041704).
  4728          */
  4729         private Type dummyMethodType(JCMethodDecl md) {
  4730             Type restype = syms.unknownType;
  4731             if (md != null && md.restype.hasTag(TYPEIDENT)) {
  4732                 JCPrimitiveTypeTree prim = (JCPrimitiveTypeTree)md.restype;
  4733                 if (prim.typetag == VOID)
  4734                     restype = syms.voidType;
  4736             return new MethodType(List.<Type>nil(), restype,
  4737                                   List.<Type>nil(), syms.methodClass);
  4739         private Type dummyMethodType() {
  4740             return dummyMethodType(null);
  4743         @Override
  4744         public void scan(JCTree tree) {
  4745             if (tree == null) return;
  4746             if (tree instanceof JCExpression) {
  4747                 initTypeIfNeeded(tree);
  4749             super.scan(tree);
  4752         @Override
  4753         public void visitIdent(JCIdent that) {
  4754             if (that.sym == null) {
  4755                 that.sym = syms.unknownSymbol;
  4759         @Override
  4760         public void visitSelect(JCFieldAccess that) {
  4761             if (that.sym == null) {
  4762                 that.sym = syms.unknownSymbol;
  4764             super.visitSelect(that);
  4767         @Override
  4768         public void visitClassDef(JCClassDecl that) {
  4769             initTypeIfNeeded(that);
  4770             if (that.sym == null) {
  4771                 that.sym = new ClassSymbol(0, that.name, that.type, syms.noSymbol);
  4773             super.visitClassDef(that);
  4776         @Override
  4777         public void visitMethodDef(JCMethodDecl that) {
  4778             initTypeIfNeeded(that);
  4779             if (that.sym == null) {
  4780                 that.sym = new MethodSymbol(0, that.name, that.type, syms.noSymbol);
  4782             super.visitMethodDef(that);
  4785         @Override
  4786         public void visitVarDef(JCVariableDecl that) {
  4787             initTypeIfNeeded(that);
  4788             if (that.sym == null) {
  4789                 that.sym = new VarSymbol(0, that.name, that.type, syms.noSymbol);
  4790                 that.sym.adr = 0;
  4792             super.visitVarDef(that);
  4795         @Override
  4796         public void visitNewClass(JCNewClass that) {
  4797             if (that.constructor == null) {
  4798                 that.constructor = new MethodSymbol(0, names.init,
  4799                         dummyMethodType(), syms.noSymbol);
  4801             if (that.constructorType == null) {
  4802                 that.constructorType = syms.unknownType;
  4804             super.visitNewClass(that);
  4807         @Override
  4808         public void visitAssignop(JCAssignOp that) {
  4809             if (that.operator == null) {
  4810                 that.operator = new OperatorSymbol(names.empty, dummyMethodType(),
  4811                         -1, syms.noSymbol);
  4813             super.visitAssignop(that);
  4816         @Override
  4817         public void visitBinary(JCBinary that) {
  4818             if (that.operator == null) {
  4819                 that.operator = new OperatorSymbol(names.empty, dummyMethodType(),
  4820                         -1, syms.noSymbol);
  4822             super.visitBinary(that);
  4825         @Override
  4826         public void visitUnary(JCUnary that) {
  4827             if (that.operator == null) {
  4828                 that.operator = new OperatorSymbol(names.empty, dummyMethodType(),
  4829                         -1, syms.noSymbol);
  4831             super.visitUnary(that);
  4834         @Override
  4835         public void visitLambda(JCLambda that) {
  4836             super.visitLambda(that);
  4837             if (that.targets == null) {
  4838                 that.targets = List.nil();
  4842         @Override
  4843         public void visitReference(JCMemberReference that) {
  4844             super.visitReference(that);
  4845             if (that.sym == null) {
  4846                 that.sym = new MethodSymbol(0, names.empty, dummyMethodType(),
  4847                         syms.noSymbol);
  4849             if (that.targets == null) {
  4850                 that.targets = List.nil();
  4854     // </editor-fold>

mercurial