Mercurial > jdk8-mips64-public > langtools / file revision

 /*

  * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.

  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

  *

  * This code is free software; you can redistribute it and/or modify it

  * under the terms of the GNU General Public License version 2 only, as

  * published by the Free Software Foundation.  Oracle designates this

  * particular file as subject to the "Classpath" exception as provided

  * by Oracle in the LICENSE file that accompanied this code.

  *

  * This code is distributed in the hope that it will be useful, but WITHOUT

  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

  * version 2 for more details (a copy is included in the LICENSE file that

  * accompanied this code).

  *

  * You should have received a copy of the GNU General Public License version

  * 2 along with this work; if not, write to the Free Software Foundation,

  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

  *

  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

  * or visit www.oracle.com if you need additional information or have any

  * questions.

  */

 package com.sun.tools.javac.comp;

 import java.util.HashMap;

 import java.util.HashSet;

 import java.util.LinkedHashMap;

 import java.util.Map;

 import java.util.Set;

 import javax.tools.JavaFileObject;

 import com.sun.tools.javac.code.*;

 import com.sun.tools.javac.jvm.*;

 import com.sun.tools.javac.tree.*;

 import com.sun.tools.javac.util.*;

 import com.sun.tools.javac.code.Type.*;

 import com.sun.tools.javac.code.Symbol.*;

 import com.sun.tools.javac.tree.JCTree.*;

 import static com.sun.tools.javac.code.Flags.*;

 import static com.sun.tools.javac.code.Flags.ANNOTATION;

 import static com.sun.tools.javac.code.Kinds.*;

 import static com.sun.tools.javac.code.TypeTag.CLASS;

 import static com.sun.tools.javac.code.TypeTag.ERROR;

 import static com.sun.tools.javac.code.TypeTag.TYPEVAR;

 import static com.sun.tools.javac.tree.JCTree.Tag.*;

 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticFlag;

 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;

 /** This is the second phase of Enter, in which classes are completed

  *  by entering their members into the class scope using

  *  MemberEnter.complete().  See Enter for an overview.

  *

  *  <p><b>This is NOT part of any supported API.

  *  If you write code that depends on this, you do so at your own risk.

  *  This code and its internal interfaces are subject to change or

  *  deletion without notice.</b>

  */

 public class MemberEnter extends JCTree.Visitor implements Completer {

     protected static final Context.Key<MemberEnter> memberEnterKey =

         new Context.Key<MemberEnter>();

     /** A switch to determine whether we check for package/class conflicts

      */

     final static boolean checkClash = true;

     private final Names names;

     private final Enter enter;

     private final Log log;

     private final Check chk;

     private final Attr attr;

     private final Symtab syms;

     private final TreeMaker make;

     private final ClassReader reader;

     private final Todo todo;

     private final Annotate annotate;

     private final TypeAnnotations typeAnnotations;

     private final Types types;

     private final JCDiagnostic.Factory diags;

     private final Source source;

     private final Target target;

     private final DeferredLintHandler deferredLintHandler;

     private final Lint lint;

     public static MemberEnter instance(Context context) {

         MemberEnter instance = context.get(memberEnterKey);

         if (instance == null)

             instance = new MemberEnter(context);

         return instance;

     }

     protected MemberEnter(Context context) {

         context.put(memberEnterKey, this);

         names = Names.instance(context);

         enter = Enter.instance(context);

         log = Log.instance(context);

         chk = Check.instance(context);

         attr = Attr.instance(context);

         syms = Symtab.instance(context);

         make = TreeMaker.instance(context);

         reader = ClassReader.instance(context);

         todo = Todo.instance(context);

         annotate = Annotate.instance(context);

         typeAnnotations = TypeAnnotations.instance(context);

         types = Types.instance(context);

         diags = JCDiagnostic.Factory.instance(context);

         source = Source.instance(context);

         target = Target.instance(context);

         deferredLintHandler = DeferredLintHandler.instance(context);

         lint = Lint.instance(context);

         allowTypeAnnos = source.allowTypeAnnotations();

         allowRepeatedAnnos = source.allowRepeatedAnnotations();

     }

     /** Switch: support type annotations.

      */

     boolean allowTypeAnnos;

     boolean allowRepeatedAnnos;

     /** A queue for classes whose members still need to be entered into the

      *  symbol table.

      */

     ListBuffer<Env<AttrContext>> halfcompleted = new ListBuffer<Env<AttrContext>>();

     /** Set to true only when the first of a set of classes is

      *  processed from the half completed queue.

      */

     boolean isFirst = true;

     /** A flag to disable completion from time to time during member

      *  enter, as we only need to look up types.  This avoids

      *  unnecessarily deep recursion.

      */

     boolean completionEnabled = true;

     /* ---------- Processing import clauses ----------------

      */

     /** Import all classes of a class or package on demand.

      *  @param pos           Position to be used for error reporting.

      *  @param tsym          The class or package the members of which are imported.

      *  @param env           The env in which the imported classes will be entered.

      */

     private void importAll(int pos,

                            final TypeSymbol tsym,

                            Env<AttrContext> env) {

         // Check that packages imported from exist (JLS ???).

         if (tsym.kind == PCK && tsym.members().elems == null && !tsym.exists()) {

             // If we can't find java.lang, exit immediately.

             if (((PackageSymbol)tsym).fullname.equals(names.java_lang)) {

                 JCDiagnostic msg = diags.fragment("fatal.err.no.java.lang");

                 throw new FatalError(msg);

             } else {

                 log.error(DiagnosticFlag.RESOLVE_ERROR, pos, "doesnt.exist", tsym);

             }

         }

         env.toplevel.starImportScope.importAll(tsym.members());

     }

     /** Import all static members of a class or package on demand.

      *  @param pos           Position to be used for error reporting.

      *  @param tsym          The class or package the members of which are imported.

      *  @param env           The env in which the imported classes will be entered.

      */

     private void importStaticAll(int pos,

                                  final TypeSymbol tsym,

                                  Env<AttrContext> env) {

         final JavaFileObject sourcefile = env.toplevel.sourcefile;

         final Scope toScope = env.toplevel.starImportScope;

         final PackageSymbol packge = env.toplevel.packge;

         final TypeSymbol origin = tsym;

         // enter imported types immediately

         new Object() {

             Set<Symbol> processed = new HashSet<Symbol>();

             void importFrom(TypeSymbol tsym) {

                 if (tsym == null || !processed.add(tsym))

                     return;

                 // also import inherited names

                 importFrom(types.supertype(tsym.type).tsym);

                 for (Type t : types.interfaces(tsym.type))

                     importFrom(t.tsym);

                 final Scope fromScope = tsym.members();

                 for (Scope.Entry e = fromScope.elems; e != null; e = e.sibling) {

                     Symbol sym = e.sym;

                     if (sym.kind == TYP &&

                         (sym.flags() & STATIC) != 0 &&

                         staticImportAccessible(sym, packge) &&

                         sym.isMemberOf(origin, types) &&

                         !toScope.includes(sym))

                         toScope.enter(sym, fromScope, origin.members(), true);

                 }

             }

         }.importFrom(tsym);

         // enter non-types before annotations that might use them

         annotate.earlier(new Annotate.Worker() {

             Set<Symbol> processed = new HashSet<Symbol>();

             public String toString() {

                 return "import static " + tsym + ".*" + " in " + sourcefile;

             }

             void importFrom(TypeSymbol tsym) {

                 if (tsym == null || !processed.add(tsym))

                     return;

                 // also import inherited names

                 importFrom(types.supertype(tsym.type).tsym);

                 for (Type t : types.interfaces(tsym.type))

                     importFrom(t.tsym);

                 final Scope fromScope = tsym.members();

                 for (Scope.Entry e = fromScope.elems; e != null; e = e.sibling) {

                     Symbol sym = e.sym;

                     if (sym.isStatic() && sym.kind != TYP &&

                         staticImportAccessible(sym, packge) &&

                         !toScope.includes(sym) &&

                         sym.isMemberOf(origin, types)) {

                         toScope.enter(sym, fromScope, origin.members(), true);

                     }

                 }

             }

             public void run() {

                 importFrom(tsym);

             }

         });

     }

     // is the sym accessible everywhere in packge?

     boolean staticImportAccessible(Symbol sym, PackageSymbol packge) {

         int flags = (int)(sym.flags() & AccessFlags);

         switch (flags) {

         default:

         case PUBLIC:

             return true;

         case PRIVATE:

             return false;

         case 0:

         case PROTECTED:

             return sym.packge() == packge;

         }

     }

     /** Import statics types of a given name.  Non-types are handled in Attr.

      *  @param pos           Position to be used for error reporting.

      *  @param tsym          The class from which the name is imported.

      *  @param name          The (simple) name being imported.

      *  @param env           The environment containing the named import

      *                  scope to add to.

      */

     private void importNamedStatic(final DiagnosticPosition pos,

                                    final TypeSymbol tsym,

                                    final Name name,

                                    final Env<AttrContext> env) {

         if (tsym.kind != TYP) {

             log.error(DiagnosticFlag.RECOVERABLE, pos, "static.imp.only.classes.and.interfaces");

             return;

         }

         final Scope toScope = env.toplevel.namedImportScope;

         final PackageSymbol packge = env.toplevel.packge;

         final TypeSymbol origin = tsym;

         // enter imported types immediately

         new Object() {

             Set<Symbol> processed = new HashSet<Symbol>();

             void importFrom(TypeSymbol tsym) {

                 if (tsym == null || !processed.add(tsym))

                     return;

                 // also import inherited names

                 importFrom(types.supertype(tsym.type).tsym);

                 for (Type t : types.interfaces(tsym.type))

                     importFrom(t.tsym);

                 for (Scope.Entry e = tsym.members().lookup(name);

                      e.scope != null;

                      e = e.next()) {

                     Symbol sym = e.sym;

                     if (sym.isStatic() &&

                         sym.kind == TYP &&

                         staticImportAccessible(sym, packge) &&

                         sym.isMemberOf(origin, types) &&

                         chk.checkUniqueStaticImport(pos, sym, toScope))

                         toScope.enter(sym, sym.owner.members(), origin.members(), true);

                 }

             }

         }.importFrom(tsym);

         // enter non-types before annotations that might use them

         annotate.earlier(new Annotate.Worker() {

             Set<Symbol> processed = new HashSet<Symbol>();

             boolean found = false;

             public String toString() {

                 return "import static " + tsym + "." + name;

             }

             void importFrom(TypeSymbol tsym) {

                 if (tsym == null || !processed.add(tsym))

                     return;

                 // also import inherited names

                 importFrom(types.supertype(tsym.type).tsym);

                 for (Type t : types.interfaces(tsym.type))

                     importFrom(t.tsym);

                 for (Scope.Entry e = tsym.members().lookup(name);

                      e.scope != null;

                      e = e.next()) {

                     Symbol sym = e.sym;

                     if (sym.isStatic() &&

                         staticImportAccessible(sym, packge) &&

                         sym.isMemberOf(origin, types)) {

                         found = true;

                         if (sym.kind != TYP) {

                             toScope.enter(sym, sym.owner.members(), origin.members(), true);

                         }

                     }

                 }

             }

             public void run() {

                 JavaFileObject prev = log.useSource(env.toplevel.sourcefile);

                 try {

                     importFrom(tsym);

                     if (!found) {

                         log.error(pos, "cant.resolve.location",

                                   KindName.STATIC,

                                   name, List.<Type>nil(), List.<Type>nil(),

                                   Kinds.typeKindName(tsym.type),

                                   tsym.type);

                     }

                 } finally {

                     log.useSource(prev);

                 }

             }

         });

     }

     /** Import given class.

      *  @param pos           Position to be used for error reporting.

      *  @param tsym          The class to be imported.

      *  @param env           The environment containing the named import

      *                  scope to add to.

      */

     private void importNamed(DiagnosticPosition pos, Symbol tsym, Env<AttrContext> env) {

         if (tsym.kind == TYP &&

             chk.checkUniqueImport(pos, tsym, env.toplevel.namedImportScope))

             env.toplevel.namedImportScope.enter(tsym, tsym.owner.members());

     }

     /** Construct method type from method signature.

      *  @param typarams    The method's type parameters.

      *  @param params      The method's value parameters.

      *  @param res             The method's result type,

      *                 null if it is a constructor.

      *  @param recvparam       The method's receiver parameter,

      *                 null if none given; TODO: or already set here?

      *  @param thrown      The method's thrown exceptions.

      *  @param env             The method's (local) environment.

      */

     Type signature(MethodSymbol msym,

                    List<JCTypeParameter> typarams,

                    List<JCVariableDecl> params,

                    JCTree res,

                    JCVariableDecl recvparam,

                    List<JCExpression> thrown,

                    Env<AttrContext> env) {

         // Enter and attribute type parameters.

         List<Type> tvars = enter.classEnter(typarams, env);

         attr.attribTypeVariables(typarams, env);

         // Enter and attribute value parameters.

         ListBuffer<Type> argbuf = new ListBuffer<Type>();

         for (List<JCVariableDecl> l = params; l.nonEmpty(); l = l.tail) {

             memberEnter(l.head, env);

             argbuf.append(l.head.vartype.type);

         }

         // Attribute result type, if one is given.

         Type restype = res == null ? syms.voidType : attr.attribType(res, env);

         // Attribute receiver type, if one is given.

         Type recvtype;

         if (recvparam!=null) {

             memberEnter(recvparam, env);

             recvtype = recvparam.vartype.type;

         } else {

             recvtype = null;

         }

         // Attribute thrown exceptions.

         ListBuffer<Type> thrownbuf = new ListBuffer<Type>();

         for (List<JCExpression> l = thrown; l.nonEmpty(); l = l.tail) {

             Type exc = attr.attribType(l.head, env);

             if (!exc.hasTag(TYPEVAR)) {

                 exc = chk.checkClassType(l.head.pos(), exc);

             } else if (exc.tsym.owner == msym) {

                 //mark inference variables in 'throws' clause

                 exc.tsym.flags_field |= THROWS;

             }

             thrownbuf.append(exc);

         }

         MethodType mtype = new MethodType(argbuf.toList(),

                                     restype,

                                     thrownbuf.toList(),

                                     syms.methodClass);

         mtype.recvtype = recvtype;

         return tvars.isEmpty() ? mtype : new ForAll(tvars, mtype);

     }

 /* ********************************************************************

  * Visitor methods for member enter

  *********************************************************************/

     /** Visitor argument: the current environment

      */

     protected Env<AttrContext> env;

     /** Enter field and method definitions and process import

      *  clauses, catching any completion failure exceptions.

      */

     protected void memberEnter(JCTree tree, Env<AttrContext> env) {

         Env<AttrContext> prevEnv = this.env;

         try {

             this.env = env;

             tree.accept(this);

         }  catch (CompletionFailure ex) {

             chk.completionError(tree.pos(), ex);

         } finally {

             this.env = prevEnv;

         }

     }

     /** Enter members from a list of trees.

      */

     void memberEnter(List<? extends JCTree> trees, Env<AttrContext> env) {

         for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)

             memberEnter(l.head, env);

     }

     /** Enter members for a class.

      */

     void finishClass(JCClassDecl tree, Env<AttrContext> env) {

         if ((tree.mods.flags & Flags.ENUM) != 0 &&

             (types.supertype(tree.sym.type).tsym.flags() & Flags.ENUM) == 0) {

             addEnumMembers(tree, env);

         }

         memberEnter(tree.defs, env);

     }

     /** Add the implicit members for an enum type

      *  to the symbol table.

      */

     private void addEnumMembers(JCClassDecl tree, Env<AttrContext> env) {

         JCExpression valuesType = make.Type(new ArrayType(tree.sym.type, syms.arrayClass));

         // public static T[] values() { return ???; }

         JCMethodDecl values = make.

             MethodDef(make.Modifiers(Flags.PUBLIC|Flags.STATIC),

                       names.values,

                       valuesType,

                       List.<JCTypeParameter>nil(),

                       List.<JCVariableDecl>nil(),

                       List.<JCExpression>nil(), // thrown

                       null, //make.Block(0, Tree.emptyList.prepend(make.Return(make.Ident(names._null)))),

                       null);

         memberEnter(values, env);

         // public static T valueOf(String name) { return ???; }

         JCMethodDecl valueOf = make.

             MethodDef(make.Modifiers(Flags.PUBLIC|Flags.STATIC),

                       names.valueOf,

                       make.Type(tree.sym.type),

                       List.<JCTypeParameter>nil(),

                       List.of(make.VarDef(make.Modifiers(Flags.PARAMETER |

                                                          Flags.MANDATED),

                                             names.fromString("name"),

                                             make.Type(syms.stringType), null)),

                       List.<JCExpression>nil(), // thrown

                       null, //make.Block(0, Tree.emptyList.prepend(make.Return(make.Ident(names._null)))),

                       null);

         memberEnter(valueOf, env);

     }

     public void visitTopLevel(JCCompilationUnit tree) {

         if (tree.starImportScope.elems != null) {

             // we must have already processed this toplevel

             return;

         }

         // check that no class exists with same fully qualified name as

         // toplevel package

         if (checkClash && tree.pid != null) {

             Symbol p = tree.packge;

             while (p.owner != syms.rootPackage) {

                 p.owner.complete(); // enter all class members of p

                 if (syms.classes.get(p.getQualifiedName()) != null) {

                     log.error(tree.pos,

                               "pkg.clashes.with.class.of.same.name",

                               p);

                 }

                 p = p.owner;

             }

         }

         // process package annotations

         annotateLater(tree.packageAnnotations, env, tree.packge, null);

         DiagnosticPosition prevLintPos = deferredLintHandler.immediate();

         Lint prevLint = chk.setLint(lint);

         try {

             // Import-on-demand java.lang.

             importAll(tree.pos, reader.enterPackage(names.java_lang), env);

             // Process all import clauses.

             memberEnter(tree.defs, env);

         } finally {

             chk.setLint(prevLint);

             deferredLintHandler.setPos(prevLintPos);

         }

     }

     // process the non-static imports and the static imports of types.

     public void visitImport(JCImport tree) {

         JCFieldAccess imp = (JCFieldAccess)tree.qualid;

         Name name = TreeInfo.name(imp);

         // Create a local environment pointing to this tree to disable

         // effects of other imports in Resolve.findGlobalType

         Env<AttrContext> localEnv = env.dup(tree);

         TypeSymbol p = attr.attribImportQualifier(tree, localEnv).tsym;

         if (name == names.asterisk) {

             // Import on demand.

             chk.checkCanonical(imp.selected);

             if (tree.staticImport)

                 importStaticAll(tree.pos, p, env);

             else

                 importAll(tree.pos, p, env);

         } else {

             // Named type import.

             if (tree.staticImport) {

                 importNamedStatic(tree.pos(), p, name, localEnv);

                 chk.checkCanonical(imp.selected);

             } else {

                 TypeSymbol c = attribImportType(imp, localEnv).tsym;

                 chk.checkCanonical(imp);

                 importNamed(tree.pos(), c, env);

             }

         }

     }

     public void visitMethodDef(JCMethodDecl tree) {

         Scope enclScope = enter.enterScope(env);

         MethodSymbol m = new MethodSymbol(0, tree.name, null, enclScope.owner);

         m.flags_field = chk.checkFlags(tree.pos(), tree.mods.flags, m, tree);

         tree.sym = m;

         //if this is a default method, add the DEFAULT flag to the enclosing interface

         if ((tree.mods.flags & DEFAULT) != 0) {

             m.enclClass().flags_field |= DEFAULT;

         }

         Env<AttrContext> localEnv = methodEnv(tree, env);

         annotate.enterStart();

         try {

             DiagnosticPosition prevLintPos = deferredLintHandler.setPos(tree.pos());

             try {

                 // Compute the method type

                 m.type = signature(m, tree.typarams, tree.params,

                                    tree.restype, tree.recvparam,

                                    tree.thrown,

                                    localEnv);

             } finally {

                 deferredLintHandler.setPos(prevLintPos);

             }

             if (types.isSignaturePolymorphic(m)) {

                 m.flags_field |= SIGNATURE_POLYMORPHIC;

             }

             // Set m.params

             ListBuffer<VarSymbol> params = new ListBuffer<VarSymbol>();

             JCVariableDecl lastParam = null;

             for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) {

                 JCVariableDecl param = lastParam = l.head;

                 params.append(Assert.checkNonNull(param.sym));

             }

             m.params = params.toList();

             // mark the method varargs, if necessary

             if (lastParam != null && (lastParam.mods.flags & Flags.VARARGS) != 0)

                 m.flags_field |= Flags.VARARGS;

             localEnv.info.scope.leave();

             if (chk.checkUnique(tree.pos(), m, enclScope)) {

             enclScope.enter(m);

             }

             annotateLater(tree.mods.annotations, localEnv, m, tree.pos());

             // Visit the signature of the method. Note that

             // TypeAnnotate doesn't descend into the body.

             typeAnnotate(tree, localEnv, m, tree.pos());

             if (tree.defaultValue != null)

                 annotateDefaultValueLater(tree.defaultValue, localEnv, m);

         } finally {

             annotate.enterDone();

         }

     }

     /** Create a fresh environment for method bodies.

      *  @param tree     The method definition.

      *  @param env      The environment current outside of the method definition.

      */

     Env<AttrContext> methodEnv(JCMethodDecl tree, Env<AttrContext> env) {

         Env<AttrContext> localEnv =

             env.dup(tree, env.info.dup(env.info.scope.dupUnshared()));

         localEnv.enclMethod = tree;

         localEnv.info.scope.owner = tree.sym;

         if (tree.sym.type != null) {

             //when this is called in the enter stage, there's no type to be set

             localEnv.info.returnResult = attr.new ResultInfo(VAL, tree.sym.type.getReturnType());

         }

         if ((tree.mods.flags & STATIC) != 0) localEnv.info.staticLevel++;

         return localEnv;

     }

     public void visitVarDef(JCVariableDecl tree) {

         Env<AttrContext> localEnv = env;

         if ((tree.mods.flags & STATIC) != 0 ||

             (env.info.scope.owner.flags() & INTERFACE) != 0) {

             localEnv = env.dup(tree, env.info.dup());

             localEnv.info.staticLevel++;

         }

         DiagnosticPosition prevLintPos = deferredLintHandler.setPos(tree.pos());

         annotate.enterStart();

         try {

             try {

                 if (TreeInfo.isEnumInit(tree)) {

                     attr.attribIdentAsEnumType(localEnv, (JCIdent)tree.vartype);

                 } else {

                     attr.attribType(tree.vartype, localEnv);

                     if (tree.nameexpr != null) {

                         attr.attribExpr(tree.nameexpr, localEnv);

                         MethodSymbol m = localEnv.enclMethod.sym;

                         if (m.isConstructor()) {

                             Type outertype = m.owner.owner.type;

                             if (outertype.hasTag(TypeTag.CLASS)) {

                                 checkType(tree.vartype, outertype, "incorrect.constructor.receiver.type");

                                 checkType(tree.nameexpr, outertype, "incorrect.constructor.receiver.name");

                             } else {

                                 log.error(tree, "receiver.parameter.not.applicable.constructor.toplevel.class");

                             }

                         } else {

                             checkType(tree.vartype, m.owner.type, "incorrect.receiver.type");

                             checkType(tree.nameexpr, m.owner.type, "incorrect.receiver.name");

                         }

                     }

                 }

             } finally {

                 deferredLintHandler.setPos(prevLintPos);

             }

             if ((tree.mods.flags & VARARGS) != 0) {

                 //if we are entering a varargs parameter, we need to

                 //replace its type (a plain array type) with the more

                 //precise VarargsType --- we need to do it this way

                 //because varargs is represented in the tree as a

                 //modifier on the parameter declaration, and not as a

                 //distinct type of array node.

                 ArrayType atype = (ArrayType)tree.vartype.type.unannotatedType();

                 tree.vartype.type = atype.makeVarargs();

             }

             Scope enclScope = enter.enterScope(env);

             VarSymbol v =

                 new VarSymbol(0, tree.name, tree.vartype.type, enclScope.owner);

             v.flags_field = chk.checkFlags(tree.pos(), tree.mods.flags, v, tree);

             tree.sym = v;

             if (tree.init != null) {

                 v.flags_field |= HASINIT;

                 if ((v.flags_field & FINAL) != 0 &&

                     needsLazyConstValue(tree.init)) {

                     Env<AttrContext> initEnv = getInitEnv(tree, env);

                     initEnv.info.enclVar = v;

                     v.setLazyConstValue(initEnv(tree, initEnv), attr, tree);

                 }

             }

             if (chk.checkUnique(tree.pos(), v, enclScope)) {

                 chk.checkTransparentVar(tree.pos(), v, enclScope);

                 enclScope.enter(v);

             }

             annotateLater(tree.mods.annotations, localEnv, v, tree.pos());

             typeAnnotate(tree.vartype, env, v, tree.pos());

             v.pos = tree.pos;

         } finally {

             annotate.enterDone();

         }

     }

     // where

     void checkType(JCTree tree, Type type, String diag) {

         if (!tree.type.isErroneous() && !types.isSameType(tree.type, type)) {

             log.error(tree, diag, type, tree.type);

         }

     }

     public boolean needsLazyConstValue(JCTree tree) {

         InitTreeVisitor initTreeVisitor = new InitTreeVisitor();

         tree.accept(initTreeVisitor);

         return initTreeVisitor.result;

     }

     /** Visitor class for expressions which might be constant expressions.

      */

     static class InitTreeVisitor extends JCTree.Visitor {

         private boolean result = true;

         @Override

         public void visitTree(JCTree tree) {}

         @Override

         public void visitNewClass(JCNewClass that) {

             result = false;

         }

         @Override

         public void visitNewArray(JCNewArray that) {

             result = false;

         }

         @Override

         public void visitLambda(JCLambda that) {

             result = false;

         }

         @Override

         public void visitReference(JCMemberReference that) {

             result = false;

         }

         @Override

         public void visitApply(JCMethodInvocation that) {

             result = false;

         }

         @Override

         public void visitSelect(JCFieldAccess tree) {

             tree.selected.accept(this);

         }

         @Override

         public void visitConditional(JCConditional tree) {

             tree.cond.accept(this);

             tree.truepart.accept(this);

             tree.falsepart.accept(this);

         }

         @Override

         public void visitParens(JCParens tree) {

             tree.expr.accept(this);

         }

         @Override

         public void visitTypeCast(JCTypeCast tree) {

             tree.expr.accept(this);

         }

     }

     /** Create a fresh environment for a variable's initializer.

      *  If the variable is a field, the owner of the environment's scope

      *  is be the variable itself, otherwise the owner is the method

      *  enclosing the variable definition.

      *

      *  @param tree     The variable definition.

      *  @param env      The environment current outside of the variable definition.

      */

     Env<AttrContext> initEnv(JCVariableDecl tree, Env<AttrContext> env) {

         Env<AttrContext> localEnv = env.dupto(new AttrContextEnv(tree, env.info.dup()));

         if (tree.sym.owner.kind == TYP) {

             localEnv.info.scope = env.info.scope.dupUnshared();

             localEnv.info.scope.owner = tree.sym;

         }

         if ((tree.mods.flags & STATIC) != 0 ||

                 ((env.enclClass.sym.flags() & INTERFACE) != 0 && env.enclMethod == null))

             localEnv.info.staticLevel++;

         return localEnv;

     }

     /** Default member enter visitor method: do nothing

      */

     public void visitTree(JCTree tree) {

     }

     public void visitErroneous(JCErroneous tree) {

         if (tree.errs != null)

             memberEnter(tree.errs, env);

     }

     public Env<AttrContext> getMethodEnv(JCMethodDecl tree, Env<AttrContext> env) {

         Env<AttrContext> mEnv = methodEnv(tree, env);

         mEnv.info.lint = mEnv.info.lint.augment(tree.sym);

         for (List<JCTypeParameter> l = tree.typarams; l.nonEmpty(); l = l.tail)

             mEnv.info.scope.enterIfAbsent(l.head.type.tsym);

         for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail)

             mEnv.info.scope.enterIfAbsent(l.head.sym);

         return mEnv;

     }

     public Env<AttrContext> getInitEnv(JCVariableDecl tree, Env<AttrContext> env) {

         Env<AttrContext> iEnv = initEnv(tree, env);

         return iEnv;

     }

 /* ********************************************************************

  * Type completion

  *********************************************************************/

     Type attribImportType(JCTree tree, Env<AttrContext> env) {

         Assert.check(completionEnabled);

         try {

             // To prevent deep recursion, suppress completion of some

             // types.

             completionEnabled = false;

             return attr.attribType(tree, env);

         } finally {

             completionEnabled = true;

         }

     }

 /* ********************************************************************

  * Annotation processing

  *********************************************************************/

     /** Queue annotations for later processing. */

     void annotateLater(final List<JCAnnotation> annotations,

                        final Env<AttrContext> localEnv,

                        final Symbol s,

                        final DiagnosticPosition deferPos) {

         if (annotations.isEmpty()) {

             return;

         }

         if (s.kind != PCK) {

             s.resetAnnotations(); // mark Annotations as incomplete for now

         }

         annotate.normal(new Annotate.Worker() {

                 @Override

                 public String toString() {

                     return "annotate " + annotations + " onto " + s + " in " + s.owner;

                 }

                 @Override

                 public void run() {

                     Assert.check(s.kind == PCK || s.annotationsPendingCompletion());

                     JavaFileObject prev = log.useSource(localEnv.toplevel.sourcefile);

                     DiagnosticPosition prevLintPos =

                         deferPos != null

                         ? deferredLintHandler.setPos(deferPos)

                         : deferredLintHandler.immediate();

                     Lint prevLint = deferPos != null ? null : chk.setLint(lint);

                     try {

                         if (s.hasAnnotations() &&

                             annotations.nonEmpty())

                             log.error(annotations.head.pos,

                                       "already.annotated",

                                       kindName(s), s);

                         actualEnterAnnotations(annotations, localEnv, s);

                     } finally {

                         if (prevLint != null)

                             chk.setLint(prevLint);

                         deferredLintHandler.setPos(prevLintPos);

                         log.useSource(prev);

                     }

                 }

             });

         annotate.validate(new Annotate.Worker() { //validate annotations

             @Override

             public void run() {

                 JavaFileObject prev = log.useSource(localEnv.toplevel.sourcefile);

                 try {

                     chk.validateAnnotations(annotations, s);

                 } finally {

                     log.useSource(prev);

                 }

             }

         });

     }

     /**

      * Check if a list of annotations contains a reference to

      * java.lang.Deprecated.

      **/

     private boolean hasDeprecatedAnnotation(List<JCAnnotation> annotations) {

         for (List<JCAnnotation> al = annotations; !al.isEmpty(); al = al.tail) {

             JCAnnotation a = al.head;

             if (a.annotationType.type == syms.deprecatedType && a.args.isEmpty())

                 return true;

         }

         return false;

     }

     /** Enter a set of annotations. */

     private void actualEnterAnnotations(List<JCAnnotation> annotations,

                           Env<AttrContext> env,

                           Symbol s) {

         Map<TypeSymbol, ListBuffer<Attribute.Compound>> annotated =

                 new LinkedHashMap<TypeSymbol, ListBuffer<Attribute.Compound>>();

         Map<Attribute.Compound, DiagnosticPosition> pos =

                 new HashMap<Attribute.Compound, DiagnosticPosition>();

         for (List<JCAnnotation> al = annotations; !al.isEmpty(); al = al.tail) {

             JCAnnotation a = al.head;

             Attribute.Compound c = annotate.enterAnnotation(a,

                                                             syms.annotationType,

                                                             env);

             if (c == null) {

                 continue;

             }

             if (annotated.containsKey(a.type.tsym)) {

                 if (!allowRepeatedAnnos) {

                     log.error(a.pos(), "repeatable.annotations.not.supported.in.source");

                     allowRepeatedAnnos = true;

                 }

                 ListBuffer<Attribute.Compound> l = annotated.get(a.type.tsym);

                 l = l.append(c);

                 annotated.put(a.type.tsym, l);

                 pos.put(c, a.pos());

             } else {

                 annotated.put(a.type.tsym, ListBuffer.of(c));

                 pos.put(c, a.pos());

             }

             // Note: @Deprecated has no effect on local variables and parameters

             if (!c.type.isErroneous()

                 && s.owner.kind != MTH

                 && types.isSameType(c.type, syms.deprecatedType)) {

                 s.flags_field |= Flags.DEPRECATED;

             }

         }

         s.setDeclarationAttributesWithCompletion(

                 annotate.new AnnotateRepeatedContext<Attribute.Compound>(env, annotated, pos, log, false));

     }

     /** Queue processing of an attribute default value. */

     void annotateDefaultValueLater(final JCExpression defaultValue,

                                    final Env<AttrContext> localEnv,

                                    final MethodSymbol m) {

         annotate.normal(new Annotate.Worker() {

                 @Override

                 public String toString() {

                     return "annotate " + m.owner + "." +

                         m + " default " + defaultValue;

                 }

                 @Override

                 public void run() {

                     JavaFileObject prev = log.useSource(localEnv.toplevel.sourcefile);

                     try {

                         enterDefaultValue(defaultValue, localEnv, m);

                     } finally {

                         log.useSource(prev);

                     }

                 }

             });

         annotate.validate(new Annotate.Worker() { //validate annotations

             @Override

             public void run() {

                 JavaFileObject prev = log.useSource(localEnv.toplevel.sourcefile);

                 try {

                     // if default value is an annotation, check it is a well-formed

                     // annotation value (e.g. no duplicate values, no missing values, etc.)

                     chk.validateAnnotationTree(defaultValue);

                 } finally {

                     log.useSource(prev);

                 }

             }

         });

     }

     /** Enter a default value for an attribute method. */

     private void enterDefaultValue(final JCExpression defaultValue,

                                    final Env<AttrContext> localEnv,

                                    final MethodSymbol m) {

         m.defaultValue = annotate.enterAttributeValue(m.type.getReturnType(),

                                                       defaultValue,

                                                       localEnv);

     }

 /* ********************************************************************

  * Source completer

  *********************************************************************/

     /** Complete entering a class.

      *  @param sym         The symbol of the class to be completed.

      */

     public void complete(Symbol sym) throws CompletionFailure {

         // Suppress some (recursive) MemberEnter invocations

         if (!completionEnabled) {

             // Re-install same completer for next time around and return.

             Assert.check((sym.flags() & Flags.COMPOUND) == 0);

             sym.completer = this;

             return;

         }

         ClassSymbol c = (ClassSymbol)sym;

         ClassType ct = (ClassType)c.type;

         Env<AttrContext> env = enter.typeEnvs.get(c);

         JCClassDecl tree = (JCClassDecl)env.tree;

         boolean wasFirst = isFirst;

         isFirst = false;

         JavaFileObject prev = log.useSource(env.toplevel.sourcefile);

         DiagnosticPosition prevLintPos = deferredLintHandler.setPos(tree.pos());

         try {

             // Save class environment for later member enter (2) processing.

             halfcompleted.append(env);

             // Mark class as not yet attributed.

             c.flags_field |= UNATTRIBUTED;

             // If this is a toplevel-class, make sure any preceding import

             // clauses have been seen.

             if (c.owner.kind == PCK) {

                 memberEnter(env.toplevel, env.enclosing(TOPLEVEL));

                 todo.append(env);

             }

             if (c.owner.kind == TYP)

                 c.owner.complete();

             // create an environment for evaluating the base clauses

             Env<AttrContext> baseEnv = baseEnv(tree, env);

             if (tree.extending != null)

                 typeAnnotate(tree.extending, baseEnv, sym, tree.pos());

             for (JCExpression impl : tree.implementing)

                 typeAnnotate(impl, baseEnv, sym, tree.pos());

             annotate.flush();

             // Determine supertype.

             Type supertype =

                 (tree.extending != null)

                 ? attr.attribBase(tree.extending, baseEnv, true, false, true)

                 : ((tree.mods.flags & Flags.ENUM) != 0)

                 ? attr.attribBase(enumBase(tree.pos, c), baseEnv,

                                   true, false, false)

                 : (c.fullname == names.java_lang_Object)

                 ? Type.noType

                 : syms.objectType;

             ct.supertype_field = modelMissingTypes(supertype, tree.extending, false);

             // Determine interfaces.

             ListBuffer<Type> interfaces = new ListBuffer<Type>();

             ListBuffer<Type> all_interfaces = null; // lazy init

             Set<Type> interfaceSet = new HashSet<Type>();

             List<JCExpression> interfaceTrees = tree.implementing;

             for (JCExpression iface : interfaceTrees) {

                 Type i = attr.attribBase(iface, baseEnv, false, true, true);

                 if (i.hasTag(CLASS)) {

                     interfaces.append(i);

                     if (all_interfaces != null) all_interfaces.append(i);

                     chk.checkNotRepeated(iface.pos(), types.erasure(i), interfaceSet);

                 } else {

                     if (all_interfaces == null)

                         all_interfaces = new ListBuffer<Type>().appendList(interfaces);

                     all_interfaces.append(modelMissingTypes(i, iface, true));

                 }

             }

             if ((c.flags_field & ANNOTATION) != 0) {

                 ct.interfaces_field = List.of(syms.annotationType);

                 ct.all_interfaces_field = ct.interfaces_field;

             }  else {

                 ct.interfaces_field = interfaces.toList();

                 ct.all_interfaces_field = (all_interfaces == null)

                         ? ct.interfaces_field : all_interfaces.toList();

             }

             if (c.fullname == names.java_lang_Object) {

                 if (tree.extending != null) {

                     chk.checkNonCyclic(tree.extending.pos(),

                                        supertype);

                     ct.supertype_field = Type.noType;

                 }

                 else if (tree.implementing.nonEmpty()) {

                     chk.checkNonCyclic(tree.implementing.head.pos(),

                                        ct.interfaces_field.head);

                     ct.interfaces_field = List.nil();

                 }

             }

             // Annotations.

             // In general, we cannot fully process annotations yet,  but we

             // can attribute the annotation types and then check to see if the

             // @Deprecated annotation is present.

             attr.attribAnnotationTypes(tree.mods.annotations, baseEnv);

             if (hasDeprecatedAnnotation(tree.mods.annotations))

                 c.flags_field |= DEPRECATED;

             annotateLater(tree.mods.annotations, baseEnv, c, tree.pos());

             // class type parameters use baseEnv but everything uses env

             chk.checkNonCyclicDecl(tree);

             attr.attribTypeVariables(tree.typarams, baseEnv);

             // Do this here, where we have the symbol.

             for (JCTypeParameter tp : tree.typarams)

                 typeAnnotate(tp, baseEnv, sym, tree.pos());

             // Add default constructor if needed.

             if ((c.flags() & INTERFACE) == 0 &&

                 !TreeInfo.hasConstructors(tree.defs)) {

                 List<Type> argtypes = List.nil();

                 List<Type> typarams = List.nil();

                 List<Type> thrown = List.nil();

                 long ctorFlags = 0;

                 boolean based = false;

                 boolean addConstructor = true;

                 JCNewClass nc = null;

                 if (c.name.isEmpty()) {

                     nc = (JCNewClass)env.next.tree;

                     if (nc.constructor != null) {

                         addConstructor = nc.constructor.kind != ERR;

                         Type superConstrType = types.memberType(c.type,

                                                                 nc.constructor);

                         argtypes = superConstrType.getParameterTypes();

                         typarams = superConstrType.getTypeArguments();

                         ctorFlags = nc.constructor.flags() & VARARGS;

                         if (nc.encl != null) {

                             argtypes = argtypes.prepend(nc.encl.type);

                             based = true;

                         }

                         thrown = superConstrType.getThrownTypes();

                     }

                 }

                 if (addConstructor) {

                     MethodSymbol basedConstructor = nc != null ?

                             (MethodSymbol)nc.constructor : null;

                     JCTree constrDef = DefaultConstructor(make.at(tree.pos), c,

                                                         basedConstructor,

                                                         typarams, argtypes, thrown,

                                                         ctorFlags, based);

                     tree.defs = tree.defs.prepend(constrDef);

                 }

             }

             // enter symbols for 'this' into current scope.

             VarSymbol thisSym =

                 new VarSymbol(FINAL | HASINIT, names._this, c.type, c);

             thisSym.pos = Position.FIRSTPOS;

             env.info.scope.enter(thisSym);

             // if this is a class, enter symbol for 'super' into current scope.

             if ((c.flags_field & INTERFACE) == 0 &&

                     ct.supertype_field.hasTag(CLASS)) {

                 VarSymbol superSym =

                     new VarSymbol(FINAL | HASINIT, names._super,

                                   ct.supertype_field, c);

                 superSym.pos = Position.FIRSTPOS;

                 env.info.scope.enter(superSym);

             }

             // check that no package exists with same fully qualified name,

             // but admit classes in the unnamed package which have the same

             // name as a top-level package.

             if (checkClash &&

                 c.owner.kind == PCK && c.owner != syms.unnamedPackage &&

                 reader.packageExists(c.fullname)) {

                 log.error(tree.pos, "clash.with.pkg.of.same.name", Kinds.kindName(sym), c);

             }

             if (c.owner.kind == PCK && (c.flags_field & PUBLIC) == 0 &&

                 !env.toplevel.sourcefile.isNameCompatible(c.name.toString(),JavaFileObject.Kind.SOURCE)) {

                 c.flags_field |= AUXILIARY;

             }

         } catch (CompletionFailure ex) {

             chk.completionError(tree.pos(), ex);

         } finally {

             deferredLintHandler.setPos(prevLintPos);

             log.useSource(prev);

         }

         // Enter all member fields and methods of a set of half completed

         // classes in a second phase.

         if (wasFirst) {

             try {

                 while (halfcompleted.nonEmpty()) {

                     Env<AttrContext> toFinish = halfcompleted.next();

                     finish(toFinish);

                     if (allowTypeAnnos) {

                         typeAnnotations.organizeTypeAnnotationsSignatures(toFinish, (JCClassDecl)toFinish.tree);

                         typeAnnotations.validateTypeAnnotationsSignatures(toFinish, (JCClassDecl)toFinish.tree);

                     }

                 }

             } finally {

                 isFirst = true;

             }

         }

     }

     /*

      * If the symbol is non-null, attach the type annotation to it.

      */

     private void actualEnterTypeAnnotations(final List<JCAnnotation> annotations,

             final Env<AttrContext> env,

             final Symbol s) {

         Map<TypeSymbol, ListBuffer<Attribute.TypeCompound>> annotated =

                 new LinkedHashMap<TypeSymbol, ListBuffer<Attribute.TypeCompound>>();

         Map<Attribute.TypeCompound, DiagnosticPosition> pos =

                 new HashMap<Attribute.TypeCompound, DiagnosticPosition>();

         for (List<JCAnnotation> al = annotations; !al.isEmpty(); al = al.tail) {

             JCAnnotation a = al.head;

             Attribute.TypeCompound tc = annotate.enterTypeAnnotation(a,

                     syms.annotationType,

                     env);

             if (tc == null) {

                 continue;

             }

             if (annotated.containsKey(a.type.tsym)) {

                 if (source.allowRepeatedAnnotations()) {

                     ListBuffer<Attribute.TypeCompound> l = annotated.get(a.type.tsym);

                     l = l.append(tc);

                     annotated.put(a.type.tsym, l);

                     pos.put(tc, a.pos());

                 } else {

                     log.error(a.pos(), "repeatable.annotations.not.supported.in.source");

                 }

             } else {

                 annotated.put(a.type.tsym, ListBuffer.of(tc));

                 pos.put(tc, a.pos());

             }

         }

         if (s != null) {

             s.appendTypeAttributesWithCompletion(

                     annotate.new AnnotateRepeatedContext<Attribute.TypeCompound>(env, annotated, pos, log, true));

         }

     }

     public void typeAnnotate(final JCTree tree, final Env<AttrContext> env, final Symbol sym, DiagnosticPosition deferPos) {

         if (allowTypeAnnos) {

             tree.accept(new TypeAnnotate(env, sym, deferPos));

         }

     }

     /**

      * We need to use a TreeScanner, because it is not enough to visit the top-level

      * annotations. We also need to visit type arguments, etc.

      */

     private class TypeAnnotate extends TreeScanner {

         private Env<AttrContext> env;

         private Symbol sym;

         private DiagnosticPosition deferPos;

         public TypeAnnotate(final Env<AttrContext> env, final Symbol sym, DiagnosticPosition deferPos) {

             this.env = env;

             this.sym = sym;

             this.deferPos = deferPos;

         }

         void annotateTypeLater(final List<JCAnnotation> annotations) {

             if (annotations.isEmpty()) {

                 return;

             }

             final DiagnosticPosition deferPos = this.deferPos;

             annotate.normal(new Annotate.Worker() {

                 @Override

                 public String toString() {

                     return "type annotate " + annotations + " onto " + sym + " in " + sym.owner;

                 }

                 @Override

                 public void run() {

                     JavaFileObject prev = log.useSource(env.toplevel.sourcefile);

                     DiagnosticPosition prevLintPos = null;

                     if (deferPos != null) {

                         prevLintPos = deferredLintHandler.setPos(deferPos);

                     }

                     try {

                         actualEnterTypeAnnotations(annotations, env, sym);

                     } finally {

                         if (prevLintPos != null)

                             deferredLintHandler.setPos(prevLintPos);

                         log.useSource(prev);

                     }

                 }

             });

         }

         @Override

         public void visitAnnotatedType(final JCAnnotatedType tree) {

             annotateTypeLater(tree.annotations);

             super.visitAnnotatedType(tree);

         }

         @Override

         public void visitTypeParameter(final JCTypeParameter tree) {

             annotateTypeLater(tree.annotations);

             super.visitTypeParameter(tree);

         }

         @Override

         public void visitNewArray(final JCNewArray tree) {

             annotateTypeLater(tree.annotations);

             for (List<JCAnnotation> dimAnnos : tree.dimAnnotations)

                 annotateTypeLater(dimAnnos);

             super.visitNewArray(tree);

         }

         @Override

         public void visitMethodDef(final JCMethodDecl tree) {

             scan(tree.mods);

             scan(tree.restype);

             scan(tree.typarams);

             scan(tree.recvparam);

             scan(tree.params);

             scan(tree.thrown);

             scan(tree.defaultValue);

             // Do not annotate the body, just the signature.

             // scan(tree.body);

         }

         @Override

         public void visitVarDef(final JCVariableDecl tree) {

             DiagnosticPosition prevPos = deferPos;

             deferPos = tree.pos();

             try {

                 if (sym != null && sym.kind == Kinds.VAR) {

                     // Don't visit a parameter once when the sym is the method

                     // and once when the sym is the parameter.

                     scan(tree.mods);

                     scan(tree.vartype);

                 }

                 scan(tree.init);

             } finally {

                 deferPos = prevPos;

             }

         }

         @Override

         public void visitClassDef(JCClassDecl tree) {

             // We can only hit a classdef if it is declared within

             // a method. Ignore it - the class will be visited

             // separately later.

         }

         @Override

         public void visitNewClass(JCNewClass tree) {

             if (tree.def == null) {

                 // For an anonymous class instantiation the class

                 // will be visited separately.

                 super.visitNewClass(tree);

             }

         }

     }

     private Env<AttrContext> baseEnv(JCClassDecl tree, Env<AttrContext> env) {

         Scope baseScope = new Scope(tree.sym);

         //import already entered local classes into base scope

         for (Scope.Entry e = env.outer.info.scope.elems ; e != null ; e = e.sibling) {

             if (e.sym.isLocal()) {

                 baseScope.enter(e.sym);

             }

         }

         //import current type-parameters into base scope

         if (tree.typarams != null)

             for (List<JCTypeParameter> typarams = tree.typarams;

                  typarams.nonEmpty();

                  typarams = typarams.tail)

                 baseScope.enter(typarams.head.type.tsym);

         Env<AttrContext> outer = env.outer; // the base clause can't see members of this class

         Env<AttrContext> localEnv = outer.dup(tree, outer.info.dup(baseScope));

         localEnv.baseClause = true;

         localEnv.outer = outer;

         localEnv.info.isSelfCall = false;

         return localEnv;

     }

     /** Enter member fields and methods of a class

      *  @param env        the environment current for the class block.

      */

     private void finish(Env<AttrContext> env) {

         JavaFileObject prev = log.useSource(env.toplevel.sourcefile);

         try {

             JCClassDecl tree = (JCClassDecl)env.tree;

             finishClass(tree, env);

         } finally {

             log.useSource(prev);

         }

     }

     /** Generate a base clause for an enum type.

      *  @param pos              The position for trees and diagnostics, if any

      *  @param c                The class symbol of the enum

      */

     private JCExpression enumBase(int pos, ClassSymbol c) {

         JCExpression result = make.at(pos).

             TypeApply(make.QualIdent(syms.enumSym),

                       List.<JCExpression>of(make.Type(c.type)));

         return result;

     }

     Type modelMissingTypes(Type t, final JCExpression tree, final boolean interfaceExpected) {

         if (!t.hasTag(ERROR))

             return t;

         return new ErrorType(t.getOriginalType(), t.tsym) {

             private Type modelType;

             @Override

             public Type getModelType() {

                 if (modelType == null)

                     modelType = new Synthesizer(getOriginalType(), interfaceExpected).visit(tree);

                 return modelType;

             }

         };

     }

     // where

     private class Synthesizer extends JCTree.Visitor {

         Type originalType;

         boolean interfaceExpected;

         List<ClassSymbol> synthesizedSymbols = List.nil();

         Type result;

         Synthesizer(Type originalType, boolean interfaceExpected) {

             this.originalType = originalType;

             this.interfaceExpected = interfaceExpected;

         }

         Type visit(JCTree tree) {

             tree.accept(this);

             return result;

         }

         List<Type> visit(List<? extends JCTree> trees) {

             ListBuffer<Type> lb = new ListBuffer<Type>();

             for (JCTree t: trees)

                 lb.append(visit(t));

             return lb.toList();

         }

         @Override

         public void visitTree(JCTree tree) {

             result = syms.errType;

         }

         @Override

         public void visitIdent(JCIdent tree) {

             if (!tree.type.hasTag(ERROR)) {

                 result = tree.type;

             } else {

                 result = synthesizeClass(tree.name, syms.unnamedPackage).type;

             }

         }

         @Override

         public void visitSelect(JCFieldAccess tree) {

             if (!tree.type.hasTag(ERROR)) {

                 result = tree.type;

             } else {

                 Type selectedType;

                 boolean prev = interfaceExpected;

                 try {

                     interfaceExpected = false;

                     selectedType = visit(tree.selected);

                 } finally {

                     interfaceExpected = prev;

                 }

                 ClassSymbol c = synthesizeClass(tree.name, selectedType.tsym);

                 result = c.type;

             }

         }

         @Override

         public void visitTypeApply(JCTypeApply tree) {

             if (!tree.type.hasTag(ERROR)) {

                 result = tree.type;

             } else {

                 ClassType clazzType = (ClassType) visit(tree.clazz);

                 if (synthesizedSymbols.contains(clazzType.tsym))

                     synthesizeTyparams((ClassSymbol) clazzType.tsym, tree.arguments.size());

                 final List<Type> actuals = visit(tree.arguments);

                 result = new ErrorType(tree.type, clazzType.tsym) {

                     @Override

                     public List<Type> getTypeArguments() {

                         return actuals;

                     }

                 };

             }

         }

         ClassSymbol synthesizeClass(Name name, Symbol owner) {

             int flags = interfaceExpected ? INTERFACE : 0;

             ClassSymbol c = new ClassSymbol(flags, name, owner);

             c.members_field = new Scope.ErrorScope(c);

             c.type = new ErrorType(originalType, c) {

                 @Override

                 public List<Type> getTypeArguments() {

                     return typarams_field;

                 }

             };

             synthesizedSymbols = synthesizedSymbols.prepend(c);

             return c;

         }

         void synthesizeTyparams(ClassSymbol sym, int n) {

             ClassType ct = (ClassType) sym.type;

             Assert.check(ct.typarams_field.isEmpty());

             if (n == 1) {

                 TypeVar v = new TypeVar(names.fromString("T"), sym, syms.botType);

                 ct.typarams_field = ct.typarams_field.prepend(v);

             } else {

                 for (int i = n; i > 0; i--) {

                     TypeVar v = new TypeVar(names.fromString("T" + i), sym, syms.botType);

                     ct.typarams_field = ct.typarams_field.prepend(v);

                 }

             }

         }

     }

 /* ***************************************************************************

  * tree building

  ****************************************************************************/

     /** Generate default constructor for given class. For classes different

      *  from java.lang.Object, this is:

      *

      *    c(argtype_0 x_0, ..., argtype_n x_n) throws thrown {

      *      super(x_0, ..., x_n)

      *    }

      *

      *  or, if based == true:

      *

      *    c(argtype_0 x_0, ..., argtype_n x_n) throws thrown {

      *      x_0.super(x_1, ..., x_n)

      *    }

      *

      *  @param make     The tree factory.

      *  @param c        The class owning the default constructor.

      *  @param argtypes The parameter types of the constructor.

      *  @param thrown   The thrown exceptions of the constructor.

      *  @param based    Is first parameter a this$n?

      */

     JCTree DefaultConstructor(TreeMaker make,

                             ClassSymbol c,

                             MethodSymbol baseInit,

                             List<Type> typarams,

                             List<Type> argtypes,

                             List<Type> thrown,

                             long flags,

                             boolean based) {

         JCTree result;

         if ((c.flags() & ENUM) != 0 &&

             (types.supertype(c.type).tsym == syms.enumSym)) {

             // constructors of true enums are private

             flags = (flags & ~AccessFlags) | PRIVATE | GENERATEDCONSTR;

         } else

             flags |= (c.flags() & AccessFlags) | GENERATEDCONSTR;

         if (c.name.isEmpty()) {

             flags |= ANONCONSTR;

         }

         Type mType = new MethodType(argtypes, null, thrown, c);

         Type initType = typarams.nonEmpty() ?

                 new ForAll(typarams, mType) :

                 mType;

         MethodSymbol init = new MethodSymbol(flags, names.init,

                 initType, c);

         init.params = createDefaultConstructorParams(make, baseInit, init,

                 argtypes, based);

         List<JCVariableDecl> params = make.Params(argtypes, init);

         List<JCStatement> stats = List.nil();

         if (c.type != syms.objectType) {

             stats = stats.prepend(SuperCall(make, typarams, params, based));

         }

         result = make.MethodDef(init, make.Block(0, stats));

         return result;

     }

     private List<VarSymbol> createDefaultConstructorParams(

             TreeMaker make,

             MethodSymbol baseInit,

             MethodSymbol init,

             List<Type> argtypes,

             boolean based) {

         List<VarSymbol> initParams = null;

         List<Type> argTypesList = argtypes;

         if (based) {

             /*  In this case argtypes will have an extra type, compared to baseInit,

              *  corresponding to the type of the enclosing instance i.e.:

              *

              *  Inner i = outer.new Inner(1){}

              *

              *  in the above example argtypes will be (Outer, int) and baseInit

              *  will have parameter's types (int). So in this case we have to add

              *  first the extra type in argtypes and then get the names of the

              *  parameters from baseInit.

              */

             initParams = List.nil();

             VarSymbol param = new VarSymbol(PARAMETER, make.paramName(0), argtypes.head, init);

             initParams = initParams.append(param);

             argTypesList = argTypesList.tail;

         }

         if (baseInit != null && baseInit.params != null &&

             baseInit.params.nonEmpty() && argTypesList.nonEmpty()) {

             initParams = (initParams == null) ? List.<VarSymbol>nil() : initParams;

             List<VarSymbol> baseInitParams = baseInit.params;

             while (baseInitParams.nonEmpty() && argTypesList.nonEmpty()) {

                 VarSymbol param = new VarSymbol(baseInitParams.head.flags() | PARAMETER,

                         baseInitParams.head.name, argTypesList.head, init);

                 initParams = initParams.append(param);

                 baseInitParams = baseInitParams.tail;

                 argTypesList = argTypesList.tail;

             }

         }

         return initParams;

     }

     /** Generate call to superclass constructor. This is:

      *

      *    super(id_0, ..., id_n)

      *

      * or, if based == true

      *

      *    id_0.super(id_1,...,id_n)

      *

      *  where id_0, ..., id_n are the names of the given parameters.

      *

      *  @param make    The tree factory

      *  @param params  The parameters that need to be passed to super

      *  @param typarams  The type parameters that need to be passed to super

      *  @param based   Is first parameter a this$n?

      */

     JCExpressionStatement SuperCall(TreeMaker make,

                    List<Type> typarams,

                    List<JCVariableDecl> params,

                    boolean based) {

         JCExpression meth;

         if (based) {

             meth = make.Select(make.Ident(params.head), names._super);

             params = params.tail;

         } else {

             meth = make.Ident(names._super);

         }

         List<JCExpression> typeargs = typarams.nonEmpty() ? make.Types(typarams) : null;

         return make.Exec(make.Apply(typeargs, meth, make.Idents(params)));

     }

 }