diff -r 000000000000 -r 959103a6100f src/share/classes/com/sun/tools/javac/comp/Check.java --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/share/classes/com/sun/tools/javac/comp/Check.java Wed Apr 27 01:34:52 2016 +0800 @@ -0,0 +1,3588 @@ +/* + * Copyright (c) 1999, 2014, 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.*; + +import javax.tools.JavaFileManager; + +import com.sun.tools.javac.code.*; +import com.sun.tools.javac.code.Attribute.Compound; +import com.sun.tools.javac.jvm.*; +import com.sun.tools.javac.tree.*; +import com.sun.tools.javac.util.*; +import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition; +import com.sun.tools.javac.util.List; + +import com.sun.tools.javac.code.Lint; +import com.sun.tools.javac.code.Lint.LintCategory; +import com.sun.tools.javac.code.Type.*; +import com.sun.tools.javac.code.Symbol.*; +import com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext; +import com.sun.tools.javac.comp.Infer.InferenceContext; +import com.sun.tools.javac.comp.Infer.FreeTypeListener; +import com.sun.tools.javac.tree.JCTree.*; +import com.sun.tools.javac.tree.JCTree.JCPolyExpression.*; + +import static com.sun.tools.javac.code.Flags.*; +import static com.sun.tools.javac.code.Flags.ANNOTATION; +import static com.sun.tools.javac.code.Flags.SYNCHRONIZED; +import static com.sun.tools.javac.code.Kinds.*; +import static com.sun.tools.javac.code.TypeTag.*; +import static com.sun.tools.javac.code.TypeTag.WILDCARD; + +import static com.sun.tools.javac.tree.JCTree.Tag.*; + +/** Type checking helper class for the attribution phase. + * + *

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. + */ +public class Check { + protected static final Context.Key checkKey = + new Context.Key(); + + private final Names names; + private final Log log; + private final Resolve rs; + private final Symtab syms; + private final Enter enter; + private final DeferredAttr deferredAttr; + private final Infer infer; + private final Types types; + private final JCDiagnostic.Factory diags; + private boolean warnOnSyntheticConflicts; + private boolean suppressAbortOnBadClassFile; + private boolean enableSunApiLintControl; + private final TreeInfo treeinfo; + private final JavaFileManager fileManager; + private final Profile profile; + private final boolean warnOnAccessToSensitiveMembers; + + // The set of lint options currently in effect. It is initialized + // from the context, and then is set/reset as needed by Attr as it + // visits all the various parts of the trees during attribution. + private Lint lint; + + // The method being analyzed in Attr - it is set/reset as needed by + // Attr as it visits new method declarations. + private MethodSymbol method; + + public static Check instance(Context context) { + Check instance = context.get(checkKey); + if (instance == null) + instance = new Check(context); + return instance; + } + + protected Check(Context context) { + context.put(checkKey, this); + + names = Names.instance(context); + dfltTargetMeta = new Name[] { names.PACKAGE, names.TYPE, + names.FIELD, names.METHOD, names.CONSTRUCTOR, + names.ANNOTATION_TYPE, names.LOCAL_VARIABLE, names.PARAMETER}; + log = Log.instance(context); + rs = Resolve.instance(context); + syms = Symtab.instance(context); + enter = Enter.instance(context); + deferredAttr = DeferredAttr.instance(context); + infer = Infer.instance(context); + types = Types.instance(context); + diags = JCDiagnostic.Factory.instance(context); + Options options = Options.instance(context); + lint = Lint.instance(context); + treeinfo = TreeInfo.instance(context); + fileManager = context.get(JavaFileManager.class); + + Source source = Source.instance(context); + allowGenerics = source.allowGenerics(); + allowVarargs = source.allowVarargs(); + allowAnnotations = source.allowAnnotations(); + allowCovariantReturns = source.allowCovariantReturns(); + allowSimplifiedVarargs = source.allowSimplifiedVarargs(); + allowDefaultMethods = source.allowDefaultMethods(); + allowStrictMethodClashCheck = source.allowStrictMethodClashCheck(); + complexInference = options.isSet("complexinference"); + warnOnSyntheticConflicts = options.isSet("warnOnSyntheticConflicts"); + suppressAbortOnBadClassFile = options.isSet("suppressAbortOnBadClassFile"); + enableSunApiLintControl = options.isSet("enableSunApiLintControl"); + warnOnAccessToSensitiveMembers = options.isSet("warnOnAccessToSensitiveMembers"); + + Target target = Target.instance(context); + syntheticNameChar = target.syntheticNameChar(); + + profile = Profile.instance(context); + + boolean verboseDeprecated = lint.isEnabled(LintCategory.DEPRECATION); + boolean verboseUnchecked = lint.isEnabled(LintCategory.UNCHECKED); + boolean verboseSunApi = lint.isEnabled(LintCategory.SUNAPI); + boolean enforceMandatoryWarnings = source.enforceMandatoryWarnings(); + + deprecationHandler = new MandatoryWarningHandler(log, verboseDeprecated, + enforceMandatoryWarnings, "deprecated", LintCategory.DEPRECATION); + uncheckedHandler = new MandatoryWarningHandler(log, verboseUnchecked, + enforceMandatoryWarnings, "unchecked", LintCategory.UNCHECKED); + sunApiHandler = new MandatoryWarningHandler(log, verboseSunApi, + enforceMandatoryWarnings, "sunapi", null); + + deferredLintHandler = DeferredLintHandler.instance(context); + } + + /** Switch: generics enabled? + */ + boolean allowGenerics; + + /** Switch: varargs enabled? + */ + boolean allowVarargs; + + /** Switch: annotations enabled? + */ + boolean allowAnnotations; + + /** Switch: covariant returns enabled? + */ + boolean allowCovariantReturns; + + /** Switch: simplified varargs enabled? + */ + boolean allowSimplifiedVarargs; + + /** Switch: default methods enabled? + */ + boolean allowDefaultMethods; + + /** Switch: should unrelated return types trigger a method clash? + */ + boolean allowStrictMethodClashCheck; + + /** Switch: -complexinference option set? + */ + boolean complexInference; + + /** Character for synthetic names + */ + char syntheticNameChar; + + /** A table mapping flat names of all compiled classes in this run to their + * symbols; maintained from outside. + */ + public Map compiled = new HashMap(); + + /** A handler for messages about deprecated usage. + */ + private MandatoryWarningHandler deprecationHandler; + + /** A handler for messages about unchecked or unsafe usage. + */ + private MandatoryWarningHandler uncheckedHandler; + + /** A handler for messages about using proprietary API. + */ + private MandatoryWarningHandler sunApiHandler; + + /** A handler for deferred lint warnings. + */ + private DeferredLintHandler deferredLintHandler; + +/* ************************************************************************* + * Errors and Warnings + **************************************************************************/ + + Lint setLint(Lint newLint) { + Lint prev = lint; + lint = newLint; + return prev; + } + + MethodSymbol setMethod(MethodSymbol newMethod) { + MethodSymbol prev = method; + method = newMethod; + return prev; + } + + /** Warn about deprecated symbol. + * @param pos Position to be used for error reporting. + * @param sym The deprecated symbol. + */ + void warnDeprecated(DiagnosticPosition pos, Symbol sym) { + if (!lint.isSuppressed(LintCategory.DEPRECATION)) + deprecationHandler.report(pos, "has.been.deprecated", sym, sym.location()); + } + + /** Warn about unchecked operation. + * @param pos Position to be used for error reporting. + * @param msg A string describing the problem. + */ + public void warnUnchecked(DiagnosticPosition pos, String msg, Object... args) { + if (!lint.isSuppressed(LintCategory.UNCHECKED)) + uncheckedHandler.report(pos, msg, args); + } + + /** Warn about unsafe vararg method decl. + * @param pos Position to be used for error reporting. + */ + void warnUnsafeVararg(DiagnosticPosition pos, String key, Object... args) { + if (lint.isEnabled(LintCategory.VARARGS) && allowSimplifiedVarargs) + log.warning(LintCategory.VARARGS, pos, key, args); + } + + /** Warn about using proprietary API. + * @param pos Position to be used for error reporting. + * @param msg A string describing the problem. + */ + public void warnSunApi(DiagnosticPosition pos, String msg, Object... args) { + if (!lint.isSuppressed(LintCategory.SUNAPI)) + sunApiHandler.report(pos, msg, args); + } + + public void warnStatic(DiagnosticPosition pos, String msg, Object... args) { + if (lint.isEnabled(LintCategory.STATIC)) + log.warning(LintCategory.STATIC, pos, msg, args); + } + + /** + * Report any deferred diagnostics. + */ + public void reportDeferredDiagnostics() { + deprecationHandler.reportDeferredDiagnostic(); + uncheckedHandler.reportDeferredDiagnostic(); + sunApiHandler.reportDeferredDiagnostic(); + } + + + /** Report a failure to complete a class. + * @param pos Position to be used for error reporting. + * @param ex The failure to report. + */ + public Type completionError(DiagnosticPosition pos, CompletionFailure ex) { + log.error(JCDiagnostic.DiagnosticFlag.NON_DEFERRABLE, pos, "cant.access", ex.sym, ex.getDetailValue()); + if (ex instanceof ClassReader.BadClassFile + && !suppressAbortOnBadClassFile) throw new Abort(); + else return syms.errType; + } + + /** Report an error that wrong type tag was found. + * @param pos Position to be used for error reporting. + * @param required An internationalized string describing the type tag + * required. + * @param found The type that was found. + */ + Type typeTagError(DiagnosticPosition pos, Object required, Object found) { + // this error used to be raised by the parser, + // but has been delayed to this point: + if (found instanceof Type && ((Type)found).hasTag(VOID)) { + log.error(pos, "illegal.start.of.type"); + return syms.errType; + } + log.error(pos, "type.found.req", found, required); + return types.createErrorType(found instanceof Type ? (Type)found : syms.errType); + } + + /** Report an error that symbol cannot be referenced before super + * has been called. + * @param pos Position to be used for error reporting. + * @param sym The referenced symbol. + */ + void earlyRefError(DiagnosticPosition pos, Symbol sym) { + log.error(pos, "cant.ref.before.ctor.called", sym); + } + + /** Report duplicate declaration error. + */ + void duplicateError(DiagnosticPosition pos, Symbol sym) { + if (!sym.type.isErroneous()) { + Symbol location = sym.location(); + if (location.kind == MTH && + ((MethodSymbol)location).isStaticOrInstanceInit()) { + log.error(pos, "already.defined.in.clinit", kindName(sym), sym, + kindName(sym.location()), kindName(sym.location().enclClass()), + sym.location().enclClass()); + } else { + log.error(pos, "already.defined", kindName(sym), sym, + kindName(sym.location()), sym.location()); + } + } + } + + /** Report array/varargs duplicate declaration + */ + void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) { + if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) { + log.error(pos, "array.and.varargs", sym1, sym2, sym2.location()); + } + } + +/* ************************************************************************ + * duplicate declaration checking + *************************************************************************/ + + /** Check that variable does not hide variable with same name in + * immediately enclosing local scope. + * @param pos Position for error reporting. + * @param v The symbol. + * @param s The scope. + */ + void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) { + if (s.next != null) { + for (Scope.Entry e = s.next.lookup(v.name); + e.scope != null && e.sym.owner == v.owner; + e = e.next()) { + if (e.sym.kind == VAR && + (e.sym.owner.kind & (VAR | MTH)) != 0 && + v.name != names.error) { + duplicateError(pos, e.sym); + return; + } + } + } + } + + /** Check that a class or interface does not hide a class or + * interface with same name in immediately enclosing local scope. + * @param pos Position for error reporting. + * @param c The symbol. + * @param s The scope. + */ + void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) { + if (s.next != null) { + for (Scope.Entry e = s.next.lookup(c.name); + e.scope != null && e.sym.owner == c.owner; + e = e.next()) { + if (e.sym.kind == TYP && !e.sym.type.hasTag(TYPEVAR) && + (e.sym.owner.kind & (VAR | MTH)) != 0 && + c.name != names.error) { + duplicateError(pos, e.sym); + return; + } + } + } + } + + /** Check that class does not have the same name as one of + * its enclosing classes, or as a class defined in its enclosing scope. + * return true if class is unique in its enclosing scope. + * @param pos Position for error reporting. + * @param name The class name. + * @param s The enclosing scope. + */ + boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) { + for (Scope.Entry e = s.lookup(name); e.scope == s; e = e.next()) { + if (e.sym.kind == TYP && e.sym.name != names.error) { + duplicateError(pos, e.sym); + return false; + } + } + for (Symbol sym = s.owner; sym != null; sym = sym.owner) { + if (sym.kind == TYP && sym.name == name && sym.name != names.error) { + duplicateError(pos, sym); + return true; + } + } + return true; + } + +/* ************************************************************************* + * Class name generation + **************************************************************************/ + + /** Return name of local class. + * This is of the form {@code $ n } + * where + * enclClass is the flat name of the enclosing class, + * classname is the simple name of the local class + */ + Name localClassName(ClassSymbol c) { + for (int i=1; ; i++) { + Name flatname = names. + fromString("" + c.owner.enclClass().flatname + + syntheticNameChar + i + + c.name); + if (compiled.get(flatname) == null) return flatname; + } + } + +/* ************************************************************************* + * Type Checking + **************************************************************************/ + + /** + * A check context is an object that can be used to perform compatibility + * checks - depending on the check context, meaning of 'compatibility' might + * vary significantly. + */ + public interface CheckContext { + /** + * Is type 'found' compatible with type 'req' in given context + */ + boolean compatible(Type found, Type req, Warner warn); + /** + * Report a check error + */ + void report(DiagnosticPosition pos, JCDiagnostic details); + /** + * Obtain a warner for this check context + */ + public Warner checkWarner(DiagnosticPosition pos, Type found, Type req); + + public Infer.InferenceContext inferenceContext(); + + public DeferredAttr.DeferredAttrContext deferredAttrContext(); + } + + /** + * This class represent a check context that is nested within another check + * context - useful to check sub-expressions. The default behavior simply + * redirects all method calls to the enclosing check context leveraging + * the forwarding pattern. + */ + static class NestedCheckContext implements CheckContext { + CheckContext enclosingContext; + + NestedCheckContext(CheckContext enclosingContext) { + this.enclosingContext = enclosingContext; + } + + public boolean compatible(Type found, Type req, Warner warn) { + return enclosingContext.compatible(found, req, warn); + } + + public void report(DiagnosticPosition pos, JCDiagnostic details) { + enclosingContext.report(pos, details); + } + + public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) { + return enclosingContext.checkWarner(pos, found, req); + } + + public Infer.InferenceContext inferenceContext() { + return enclosingContext.inferenceContext(); + } + + public DeferredAttrContext deferredAttrContext() { + return enclosingContext.deferredAttrContext(); + } + } + + /** + * Check context to be used when evaluating assignment/return statements + */ + CheckContext basicHandler = new CheckContext() { + public void report(DiagnosticPosition pos, JCDiagnostic details) { + log.error(pos, "prob.found.req", details); + } + public boolean compatible(Type found, Type req, Warner warn) { + return types.isAssignable(found, req, warn); + } + + public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) { + return convertWarner(pos, found, req); + } + + public InferenceContext inferenceContext() { + return infer.emptyContext; + } + + public DeferredAttrContext deferredAttrContext() { + return deferredAttr.emptyDeferredAttrContext; + } + + @Override + public String toString() { + return "CheckContext: basicHandler"; + } + }; + + /** Check that a given type is assignable to a given proto-type. + * If it is, return the type, otherwise return errType. + * @param pos Position to be used for error reporting. + * @param found The type that was found. + * @param req The type that was required. + */ + Type checkType(DiagnosticPosition pos, Type found, Type req) { + return checkType(pos, found, req, basicHandler); + } + + Type checkType(final DiagnosticPosition pos, final Type found, final Type req, final CheckContext checkContext) { + final Infer.InferenceContext inferenceContext = checkContext.inferenceContext(); + if (inferenceContext.free(req)) { + inferenceContext.addFreeTypeListener(List.of(req), new FreeTypeListener() { + @Override + public void typesInferred(InferenceContext inferenceContext) { + checkType(pos, inferenceContext.asInstType(found), inferenceContext.asInstType(req), checkContext); + } + }); + } + if (req.hasTag(ERROR)) + return req; + if (req.hasTag(NONE)) + return found; + if (checkContext.compatible(found, req, checkContext.checkWarner(pos, found, req))) { + return found; + } else { + if (found.isNumeric() && req.isNumeric()) { + checkContext.report(pos, diags.fragment("possible.loss.of.precision", found, req)); + return types.createErrorType(found); + } + checkContext.report(pos, diags.fragment("inconvertible.types", found, req)); + return types.createErrorType(found); + } + } + + /** Check that a given type can be cast to a given target type. + * Return the result of the cast. + * @param pos Position to be used for error reporting. + * @param found The type that is being cast. + * @param req The target type of the cast. + */ + Type checkCastable(DiagnosticPosition pos, Type found, Type req) { + return checkCastable(pos, found, req, basicHandler); + } + Type checkCastable(DiagnosticPosition pos, Type found, Type req, CheckContext checkContext) { + if (types.isCastable(found, req, castWarner(pos, found, req))) { + return req; + } else { + checkContext.report(pos, diags.fragment("inconvertible.types", found, req)); + return types.createErrorType(found); + } + } + + /** Check for redundant casts (i.e. where source type is a subtype of target type) + * The problem should only be reported for non-292 cast + */ + public void checkRedundantCast(Env env, final JCTypeCast tree) { + if (!tree.type.isErroneous() + && types.isSameType(tree.expr.type, tree.clazz.type) + && !(ignoreAnnotatedCasts && TreeInfo.containsTypeAnnotation(tree.clazz)) + && !is292targetTypeCast(tree)) { + deferredLintHandler.report(new DeferredLintHandler.LintLogger() { + @Override + public void report() { + if (lint.isEnabled(Lint.LintCategory.CAST)) + log.warning(Lint.LintCategory.CAST, + tree.pos(), "redundant.cast", tree.expr.type); + } + }); + } + } + //where + private boolean is292targetTypeCast(JCTypeCast tree) { + boolean is292targetTypeCast = false; + JCExpression expr = TreeInfo.skipParens(tree.expr); + if (expr.hasTag(APPLY)) { + JCMethodInvocation apply = (JCMethodInvocation)expr; + Symbol sym = TreeInfo.symbol(apply.meth); + is292targetTypeCast = sym != null && + sym.kind == MTH && + (sym.flags() & HYPOTHETICAL) != 0; + } + return is292targetTypeCast; + } + + private static final boolean ignoreAnnotatedCasts = true; + + /** Check that a type is within some bounds. + * + * Used in TypeApply to verify that, e.g., X in {@code V} is a valid + * type argument. + * @param a The type that should be bounded by bs. + * @param bound The bound. + */ + private boolean checkExtends(Type a, Type bound) { + if (a.isUnbound()) { + return true; + } else if (!a.hasTag(WILDCARD)) { + a = types.cvarUpperBound(a); + return types.isSubtype(a, bound); + } else if (a.isExtendsBound()) { + return types.isCastable(bound, types.wildUpperBound(a), types.noWarnings); + } else if (a.isSuperBound()) { + return !types.notSoftSubtype(types.wildLowerBound(a), bound); + } + return true; + } + + /** Check that type is different from 'void'. + * @param pos Position to be used for error reporting. + * @param t The type to be checked. + */ + Type checkNonVoid(DiagnosticPosition pos, Type t) { + if (t.hasTag(VOID)) { + log.error(pos, "void.not.allowed.here"); + return types.createErrorType(t); + } else { + return t; + } + } + + Type checkClassOrArrayType(DiagnosticPosition pos, Type t) { + if (!t.hasTag(CLASS) && !t.hasTag(ARRAY) && !t.hasTag(ERROR)) { + return typeTagError(pos, + diags.fragment("type.req.class.array"), + asTypeParam(t)); + } else { + return t; + } + } + + /** Check that type is a class or interface type. + * @param pos Position to be used for error reporting. + * @param t The type to be checked. + */ + Type checkClassType(DiagnosticPosition pos, Type t) { + if (!t.hasTag(CLASS) && !t.hasTag(ERROR)) { + return typeTagError(pos, + diags.fragment("type.req.class"), + asTypeParam(t)); + } else { + return t; + } + } + //where + private Object asTypeParam(Type t) { + return (t.hasTag(TYPEVAR)) + ? diags.fragment("type.parameter", t) + : t; + } + + /** Check that type is a valid qualifier for a constructor reference expression + */ + Type checkConstructorRefType(DiagnosticPosition pos, Type t) { + t = checkClassOrArrayType(pos, t); + if (t.hasTag(CLASS)) { + if ((t.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) { + log.error(pos, "abstract.cant.be.instantiated", t.tsym); + t = types.createErrorType(t); + } else if ((t.tsym.flags() & ENUM) != 0) { + log.error(pos, "enum.cant.be.instantiated"); + t = types.createErrorType(t); + } else { + t = checkClassType(pos, t, true); + } + } else if (t.hasTag(ARRAY)) { + if (!types.isReifiable(((ArrayType)t).elemtype)) { + log.error(pos, "generic.array.creation"); + t = types.createErrorType(t); + } + } + return t; + } + + /** Check that type is a class or interface type. + * @param pos Position to be used for error reporting. + * @param t The type to be checked. + * @param noBounds True if type bounds are illegal here. + */ + Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) { + t = checkClassType(pos, t); + if (noBounds && t.isParameterized()) { + List args = t.getTypeArguments(); + while (args.nonEmpty()) { + if (args.head.hasTag(WILDCARD)) + return typeTagError(pos, + diags.fragment("type.req.exact"), + args.head); + args = args.tail; + } + } + return t; + } + + /** Check that type is a reference type, i.e. a class, interface or array type + * or a type variable. + * @param pos Position to be used for error reporting. + * @param t The type to be checked. + */ + Type checkRefType(DiagnosticPosition pos, Type t) { + if (t.isReference()) + return t; + else + return typeTagError(pos, + diags.fragment("type.req.ref"), + t); + } + + /** Check that each type is a reference type, i.e. a class, interface or array type + * or a type variable. + * @param trees Original trees, used for error reporting. + * @param types The types to be checked. + */ + List checkRefTypes(List trees, List types) { + List tl = trees; + for (List l = types; l.nonEmpty(); l = l.tail) { + l.head = checkRefType(tl.head.pos(), l.head); + tl = tl.tail; + } + return types; + } + + /** Check that type is a null or reference type. + * @param pos Position to be used for error reporting. + * @param t The type to be checked. + */ + Type checkNullOrRefType(DiagnosticPosition pos, Type t) { + if (t.isReference() || t.hasTag(BOT)) + return t; + else + return typeTagError(pos, + diags.fragment("type.req.ref"), + t); + } + + /** Check that flag set does not contain elements of two conflicting sets. s + * Return true if it doesn't. + * @param pos Position to be used for error reporting. + * @param flags The set of flags to be checked. + * @param set1 Conflicting flags set #1. + * @param set2 Conflicting flags set #2. + */ + boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) { + if ((flags & set1) != 0 && (flags & set2) != 0) { + log.error(pos, + "illegal.combination.of.modifiers", + asFlagSet(TreeInfo.firstFlag(flags & set1)), + asFlagSet(TreeInfo.firstFlag(flags & set2))); + return false; + } else + return true; + } + + /** Check that usage of diamond operator is correct (i.e. diamond should not + * be used with non-generic classes or in anonymous class creation expressions) + */ + Type checkDiamond(JCNewClass tree, Type t) { + if (!TreeInfo.isDiamond(tree) || + t.isErroneous()) { + return checkClassType(tree.clazz.pos(), t, true); + } else if (tree.def != null) { + log.error(tree.clazz.pos(), + "cant.apply.diamond.1", + t, diags.fragment("diamond.and.anon.class", t)); + return types.createErrorType(t); + } else if (t.tsym.type.getTypeArguments().isEmpty()) { + log.error(tree.clazz.pos(), + "cant.apply.diamond.1", + t, diags.fragment("diamond.non.generic", t)); + return types.createErrorType(t); + } else if (tree.typeargs != null && + tree.typeargs.nonEmpty()) { + log.error(tree.clazz.pos(), + "cant.apply.diamond.1", + t, diags.fragment("diamond.and.explicit.params", t)); + return types.createErrorType(t); + } else { + return t; + } + } + + void checkVarargsMethodDecl(Env env, JCMethodDecl tree) { + MethodSymbol m = tree.sym; + if (!allowSimplifiedVarargs) return; + boolean hasTrustMeAnno = m.attribute(syms.trustMeType.tsym) != null; + Type varargElemType = null; + if (m.isVarArgs()) { + varargElemType = types.elemtype(tree.params.last().type); + } + if (hasTrustMeAnno && !isTrustMeAllowedOnMethod(m)) { + if (varargElemType != null) { + log.error(tree, + "varargs.invalid.trustme.anno", + syms.trustMeType.tsym, + diags.fragment("varargs.trustme.on.virtual.varargs", m)); + } else { + log.error(tree, + "varargs.invalid.trustme.anno", + syms.trustMeType.tsym, + diags.fragment("varargs.trustme.on.non.varargs.meth", m)); + } + } else if (hasTrustMeAnno && varargElemType != null && + types.isReifiable(varargElemType)) { + warnUnsafeVararg(tree, + "varargs.redundant.trustme.anno", + syms.trustMeType.tsym, + diags.fragment("varargs.trustme.on.reifiable.varargs", varargElemType)); + } + else if (!hasTrustMeAnno && varargElemType != null && + !types.isReifiable(varargElemType)) { + warnUnchecked(tree.params.head.pos(), "unchecked.varargs.non.reifiable.type", varargElemType); + } + } + //where + private boolean isTrustMeAllowedOnMethod(Symbol s) { + return (s.flags() & VARARGS) != 0 && + (s.isConstructor() || + (s.flags() & (STATIC | FINAL)) != 0); + } + + Type checkMethod(final Type mtype, + final Symbol sym, + final Env env, + final List argtrees, + final List argtypes, + final boolean useVarargs, + InferenceContext inferenceContext) { + // System.out.println("call : " + env.tree); + // System.out.println("method : " + owntype); + // System.out.println("actuals: " + argtypes); + if (inferenceContext.free(mtype)) { + inferenceContext.addFreeTypeListener(List.of(mtype), new FreeTypeListener() { + public void typesInferred(InferenceContext inferenceContext) { + checkMethod(inferenceContext.asInstType(mtype), sym, env, argtrees, argtypes, useVarargs, inferenceContext); + } + }); + return mtype; + } + Type owntype = mtype; + List formals = owntype.getParameterTypes(); + List nonInferred = sym.type.getParameterTypes(); + if (nonInferred.length() != formals.length()) nonInferred = formals; + Type last = useVarargs ? formals.last() : null; + if (sym.name == names.init && sym.owner == syms.enumSym) { + formals = formals.tail.tail; + nonInferred = nonInferred.tail.tail; + } + List args = argtrees; + if (args != null) { + //this is null when type-checking a method reference + while (formals.head != last) { + JCTree arg = args.head; + Warner warn = convertWarner(arg.pos(), arg.type, nonInferred.head); + assertConvertible(arg, arg.type, formals.head, warn); + args = args.tail; + formals = formals.tail; + nonInferred = nonInferred.tail; + } + if (useVarargs) { + Type varArg = types.elemtype(last); + while (args.tail != null) { + JCTree arg = args.head; + Warner warn = convertWarner(arg.pos(), arg.type, varArg); + assertConvertible(arg, arg.type, varArg, warn); + args = args.tail; + } + } else if ((sym.flags() & (VARARGS | SIGNATURE_POLYMORPHIC)) == VARARGS && + allowVarargs) { + // non-varargs call to varargs method + Type varParam = owntype.getParameterTypes().last(); + Type lastArg = argtypes.last(); + if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) && + !types.isSameType(types.erasure(varParam), types.erasure(lastArg))) + log.warning(argtrees.last().pos(), "inexact.non-varargs.call", + types.elemtype(varParam), varParam); + } + } + if (useVarargs) { + Type argtype = owntype.getParameterTypes().last(); + if (!types.isReifiable(argtype) && + (!allowSimplifiedVarargs || + sym.attribute(syms.trustMeType.tsym) == null || + !isTrustMeAllowedOnMethod(sym))) { + warnUnchecked(env.tree.pos(), + "unchecked.generic.array.creation", + argtype); + } + if ((sym.baseSymbol().flags() & SIGNATURE_POLYMORPHIC) == 0) { + TreeInfo.setVarargsElement(env.tree, types.elemtype(argtype)); + } + } + PolyKind pkind = (sym.type.hasTag(FORALL) && + sym.type.getReturnType().containsAny(((ForAll)sym.type).tvars)) ? + PolyKind.POLY : PolyKind.STANDALONE; + TreeInfo.setPolyKind(env.tree, pkind); + return owntype; + } + //where + private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) { + if (types.isConvertible(actual, formal, warn)) + return; + + if (formal.isCompound() + && types.isSubtype(actual, types.supertype(formal)) + && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn)) + return; + } + + /** + * Check that type 't' is a valid instantiation of a generic class + * (see JLS 4.5) + * + * @param t class type to be checked + * @return true if 't' is well-formed + */ + public boolean checkValidGenericType(Type t) { + return firstIncompatibleTypeArg(t) == null; + } + //WHERE + private Type firstIncompatibleTypeArg(Type type) { + List formals = type.tsym.type.allparams(); + List actuals = type.allparams(); + List args = type.getTypeArguments(); + List forms = type.tsym.type.getTypeArguments(); + ListBuffer bounds_buf = new ListBuffer(); + + // For matching pairs of actual argument types `a' and + // formal type parameters with declared bound `b' ... + while (args.nonEmpty() && forms.nonEmpty()) { + // exact type arguments needs to know their + // bounds (for upper and lower bound + // calculations). So we create new bounds where + // type-parameters are replaced with actuals argument types. + bounds_buf.append(types.subst(forms.head.getUpperBound(), formals, actuals)); + args = args.tail; + forms = forms.tail; + } + + args = type.getTypeArguments(); + List tvars_cap = types.substBounds(formals, + formals, + types.capture(type).allparams()); + while (args.nonEmpty() && tvars_cap.nonEmpty()) { + // Let the actual arguments know their bound + args.head.withTypeVar((TypeVar)tvars_cap.head); + args = args.tail; + tvars_cap = tvars_cap.tail; + } + + args = type.getTypeArguments(); + List bounds = bounds_buf.toList(); + + while (args.nonEmpty() && bounds.nonEmpty()) { + Type actual = args.head; + if (!isTypeArgErroneous(actual) && + !bounds.head.isErroneous() && + !checkExtends(actual, bounds.head)) { + return args.head; + } + args = args.tail; + bounds = bounds.tail; + } + + args = type.getTypeArguments(); + bounds = bounds_buf.toList(); + + for (Type arg : types.capture(type).getTypeArguments()) { + if (arg.hasTag(TYPEVAR) && + arg.getUpperBound().isErroneous() && + !bounds.head.isErroneous() && + !isTypeArgErroneous(args.head)) { + return args.head; + } + bounds = bounds.tail; + args = args.tail; + } + + return null; + } + //where + boolean isTypeArgErroneous(Type t) { + return isTypeArgErroneous.visit(t); + } + + Types.UnaryVisitor isTypeArgErroneous = new Types.UnaryVisitor() { + public Boolean visitType(Type t, Void s) { + return t.isErroneous(); + } + @Override + public Boolean visitTypeVar(TypeVar t, Void s) { + return visit(t.getUpperBound()); + } + @Override + public Boolean visitCapturedType(CapturedType t, Void s) { + return visit(t.getUpperBound()) || + visit(t.getLowerBound()); + } + @Override + public Boolean visitWildcardType(WildcardType t, Void s) { + return visit(t.type); + } + }; + + /** Check that given modifiers are legal for given symbol and + * return modifiers together with any implicit modifiers for that symbol. + * Warning: we can't use flags() here since this method + * is called during class enter, when flags() would cause a premature + * completion. + * @param pos Position to be used for error reporting. + * @param flags The set of modifiers given in a definition. + * @param sym The defined symbol. + */ + long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) { + long mask; + long implicit = 0; + + switch (sym.kind) { + case VAR: + if (TreeInfo.isReceiverParam(tree)) + mask = ReceiverParamFlags; + else if (sym.owner.kind != TYP) + mask = LocalVarFlags; + else if ((sym.owner.flags_field & INTERFACE) != 0) + mask = implicit = InterfaceVarFlags; + else + mask = VarFlags; + break; + case MTH: + if (sym.name == names.init) { + if ((sym.owner.flags_field & ENUM) != 0) { + // enum constructors cannot be declared public or + // protected and must be implicitly or explicitly + // private + implicit = PRIVATE; + mask = PRIVATE; + } else + mask = ConstructorFlags; + } else if ((sym.owner.flags_field & INTERFACE) != 0) { + if ((sym.owner.flags_field & ANNOTATION) != 0) { + mask = AnnotationTypeElementMask; + implicit = PUBLIC | ABSTRACT; + } else if ((flags & (DEFAULT | STATIC)) != 0) { + mask = InterfaceMethodMask; + implicit = PUBLIC; + if ((flags & DEFAULT) != 0) { + implicit |= ABSTRACT; + } + } else { + mask = implicit = InterfaceMethodFlags; + } + } else { + mask = MethodFlags; + } + // Imply STRICTFP if owner has STRICTFP set. + if (((flags|implicit) & Flags.ABSTRACT) == 0 || + ((flags) & Flags.DEFAULT) != 0) + implicit |= sym.owner.flags_field & STRICTFP; + break; + case TYP: + if (sym.isLocal()) { + mask = LocalClassFlags; + if (sym.name.isEmpty()) { // Anonymous class + // Anonymous classes in static methods are themselves static; + // that's why we admit STATIC here. + mask |= STATIC; + // JLS: Anonymous classes are final. + implicit |= FINAL; + } + if ((sym.owner.flags_field & STATIC) == 0 && + (flags & ENUM) != 0) + log.error(pos, "enums.must.be.static"); + } else if (sym.owner.kind == TYP) { + mask = MemberClassFlags; + if (sym.owner.owner.kind == PCK || + (sym.owner.flags_field & STATIC) != 0) + mask |= STATIC; + else if ((flags & ENUM) != 0) + log.error(pos, "enums.must.be.static"); + // Nested interfaces and enums are always STATIC (Spec ???) + if ((flags & (INTERFACE | ENUM)) != 0 ) implicit = STATIC; + } else { + mask = ClassFlags; + } + // Interfaces are always ABSTRACT + if ((flags & INTERFACE) != 0) implicit |= ABSTRACT; + + if ((flags & ENUM) != 0) { + // enums can't be declared abstract or final + mask &= ~(ABSTRACT | FINAL); + implicit |= implicitEnumFinalFlag(tree); + } + // Imply STRICTFP if owner has STRICTFP set. + implicit |= sym.owner.flags_field & STRICTFP; + break; + default: + throw new AssertionError(); + } + long illegal = flags & ExtendedStandardFlags & ~mask; + if (illegal != 0) { + if ((illegal & INTERFACE) != 0) { + log.error(pos, "intf.not.allowed.here"); + mask |= INTERFACE; + } + else { + log.error(pos, + "mod.not.allowed.here", asFlagSet(illegal)); + } + } + else if ((sym.kind == TYP || + // ISSUE: Disallowing abstract&private is no longer appropriate + // in the presence of inner classes. Should it be deleted here? + checkDisjoint(pos, flags, + ABSTRACT, + PRIVATE | STATIC | DEFAULT)) + && + checkDisjoint(pos, flags, + STATIC, + DEFAULT) + && + checkDisjoint(pos, flags, + ABSTRACT | INTERFACE, + FINAL | NATIVE | SYNCHRONIZED) + && + checkDisjoint(pos, flags, + PUBLIC, + PRIVATE | PROTECTED) + && + checkDisjoint(pos, flags, + PRIVATE, + PUBLIC | PROTECTED) + && + checkDisjoint(pos, flags, + FINAL, + VOLATILE) + && + (sym.kind == TYP || + checkDisjoint(pos, flags, + ABSTRACT | NATIVE, + STRICTFP))) { + // skip + } + return flags & (mask | ~ExtendedStandardFlags) | implicit; + } + + + /** Determine if this enum should be implicitly final. + * + * If the enum has no specialized enum contants, it is final. + * + * If the enum does have specialized enum contants, it is + * not final. + */ + private long implicitEnumFinalFlag(JCTree tree) { + if (!tree.hasTag(CLASSDEF)) return 0; + class SpecialTreeVisitor extends JCTree.Visitor { + boolean specialized; + SpecialTreeVisitor() { + this.specialized = false; + }; + + @Override + public void visitTree(JCTree tree) { /* no-op */ } + + @Override + public void visitVarDef(JCVariableDecl tree) { + if ((tree.mods.flags & ENUM) != 0) { + if (tree.init instanceof JCNewClass && + ((JCNewClass) tree.init).def != null) { + specialized = true; + } + } + } + } + + SpecialTreeVisitor sts = new SpecialTreeVisitor(); + JCClassDecl cdef = (JCClassDecl) tree; + for (JCTree defs: cdef.defs) { + defs.accept(sts); + if (sts.specialized) return 0; + } + return FINAL; + } + +/* ************************************************************************* + * Type Validation + **************************************************************************/ + + /** Validate a type expression. That is, + * check that all type arguments of a parametric type are within + * their bounds. This must be done in a second phase after type attribution + * since a class might have a subclass as type parameter bound. E.g: + * + * 

{@code
+     *  class B { ... }
+     *  class C extends B { ... }
+     *  }
+ * + * and we can't make sure that the bound is already attributed because + * of possible cycles. + * + * Visitor method: Validate a type expression, if it is not null, catching + * and reporting any completion failures. + */ + void validate(JCTree tree, Env env) { + validate(tree, env, true); + } + void validate(JCTree tree, Env env, boolean checkRaw) { + new Validator(env).validateTree(tree, checkRaw, true); + } + + /** Visitor method: Validate a list of type expressions. + */ + void validate(List trees, Env env) { + for (List l = trees; l.nonEmpty(); l = l.tail) + validate(l.head, env); + } + + /** A visitor class for type validation. + */ + class Validator extends JCTree.Visitor { + + boolean checkRaw; + boolean isOuter; + Env env; + + Validator(Env env) { + this.env = env; + } + + @Override + public void visitTypeArray(JCArrayTypeTree tree) { + validateTree(tree.elemtype, checkRaw, isOuter); + } + + @Override + public void visitTypeApply(JCTypeApply tree) { + if (tree.type.hasTag(CLASS)) { + List args = tree.arguments; + List forms = tree.type.tsym.type.getTypeArguments(); + + Type incompatibleArg = firstIncompatibleTypeArg(tree.type); + if (incompatibleArg != null) { + for (JCTree arg : tree.arguments) { + if (arg.type == incompatibleArg) { + log.error(arg, "not.within.bounds", incompatibleArg, forms.head); + } + forms = forms.tail; + } + } + + forms = tree.type.tsym.type.getTypeArguments(); + + boolean is_java_lang_Class = tree.type.tsym.flatName() == names.java_lang_Class; + + // For matching pairs of actual argument types `a' and + // formal type parameters with declared bound `b' ... + while (args.nonEmpty() && forms.nonEmpty()) { + validateTree(args.head, + !(isOuter && is_java_lang_Class), + false); + args = args.tail; + forms = forms.tail; + } + + // Check that this type is either fully parameterized, or + // not parameterized at all. + if (tree.type.getEnclosingType().isRaw()) + log.error(tree.pos(), "improperly.formed.type.inner.raw.param"); + if (tree.clazz.hasTag(SELECT)) + visitSelectInternal((JCFieldAccess)tree.clazz); + } + } + + @Override + public void visitTypeParameter(JCTypeParameter tree) { + validateTrees(tree.bounds, true, isOuter); + checkClassBounds(tree.pos(), tree.type); + } + + @Override + public void visitWildcard(JCWildcard tree) { + if (tree.inner != null) + validateTree(tree.inner, true, isOuter); + } + + @Override + public void visitSelect(JCFieldAccess tree) { + if (tree.type.hasTag(CLASS)) { + visitSelectInternal(tree); + + // Check that this type is either fully parameterized, or + // not parameterized at all. + if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty()) + log.error(tree.pos(), "improperly.formed.type.param.missing"); + } + } + + public void visitSelectInternal(JCFieldAccess tree) { + if (tree.type.tsym.isStatic() && + tree.selected.type.isParameterized()) { + // The enclosing type is not a class, so we are + // looking at a static member type. However, the + // qualifying expression is parameterized. + log.error(tree.pos(), "cant.select.static.class.from.param.type"); + } else { + // otherwise validate the rest of the expression + tree.selected.accept(this); + } + } + + @Override + public void visitAnnotatedType(JCAnnotatedType tree) { + tree.underlyingType.accept(this); + } + + @Override + public void visitTypeIdent(JCPrimitiveTypeTree that) { + if (that.type.hasTag(TypeTag.VOID)) { + log.error(that.pos(), "void.not.allowed.here"); + } + super.visitTypeIdent(that); + } + + /** Default visitor method: do nothing. + */ + @Override + public void visitTree(JCTree tree) { + } + + public void validateTree(JCTree tree, boolean checkRaw, boolean isOuter) { + if (tree != null) { + boolean prevCheckRaw = this.checkRaw; + this.checkRaw = checkRaw; + this.isOuter = isOuter; + + try { + tree.accept(this); + if (checkRaw) + checkRaw(tree, env); + } catch (CompletionFailure ex) { + completionError(tree.pos(), ex); + } finally { + this.checkRaw = prevCheckRaw; + } + } + } + + public void validateTrees(List trees, boolean checkRaw, boolean isOuter) { + for (List l = trees; l.nonEmpty(); l = l.tail) + validateTree(l.head, checkRaw, isOuter); + } + } + + void checkRaw(JCTree tree, Env env) { + if (lint.isEnabled(LintCategory.RAW) && + tree.type.hasTag(CLASS) && + !TreeInfo.isDiamond(tree) && + !withinAnonConstr(env) && + tree.type.isRaw()) { + log.warning(LintCategory.RAW, + tree.pos(), "raw.class.use", tree.type, tree.type.tsym.type); + } + } + //where + private boolean withinAnonConstr(Env env) { + return env.enclClass.name.isEmpty() && + env.enclMethod != null && env.enclMethod.name == names.init; + } + +/* ************************************************************************* + * Exception checking + **************************************************************************/ + + /* The following methods treat classes as sets that contain + * the class itself and all their subclasses + */ + + /** Is given type a subtype of some of the types in given list? + */ + boolean subset(Type t, List ts) { + for (List l = ts; l.nonEmpty(); l = l.tail) + if (types.isSubtype(t, l.head)) return true; + return false; + } + + /** Is given type a subtype or supertype of + * some of the types in given list? + */ + boolean intersects(Type t, List ts) { + for (List l = ts; l.nonEmpty(); l = l.tail) + if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true; + return false; + } + + /** Add type set to given type list, unless it is a subclass of some class + * in the list. + */ + List incl(Type t, List ts) { + return subset(t, ts) ? ts : excl(t, ts).prepend(t); + } + + /** Remove type set from type set list. + */ + List excl(Type t, List ts) { + if (ts.isEmpty()) { + return ts; + } else { + List ts1 = excl(t, ts.tail); + if (types.isSubtype(ts.head, t)) return ts1; + else if (ts1 == ts.tail) return ts; + else return ts1.prepend(ts.head); + } + } + + /** Form the union of two type set lists. + */ + List union(List ts1, List ts2) { + List ts = ts1; + for (List l = ts2; l.nonEmpty(); l = l.tail) + ts = incl(l.head, ts); + return ts; + } + + /** Form the difference of two type lists. + */ + List diff(List ts1, List ts2) { + List ts = ts1; + for (List l = ts2; l.nonEmpty(); l = l.tail) + ts = excl(l.head, ts); + return ts; + } + + /** Form the intersection of two type lists. + */ + public List intersect(List ts1, List ts2) { + List ts = List.nil(); + for (List l = ts1; l.nonEmpty(); l = l.tail) + if (subset(l.head, ts2)) ts = incl(l.head, ts); + for (List l = ts2; l.nonEmpty(); l = l.tail) + if (subset(l.head, ts1)) ts = incl(l.head, ts); + return ts; + } + + /** Is exc an exception symbol that need not be declared? + */ + boolean isUnchecked(ClassSymbol exc) { + return + exc.kind == ERR || + exc.isSubClass(syms.errorType.tsym, types) || + exc.isSubClass(syms.runtimeExceptionType.tsym, types); + } + + /** Is exc an exception type that need not be declared? + */ + boolean isUnchecked(Type exc) { + return + (exc.hasTag(TYPEVAR)) ? isUnchecked(types.supertype(exc)) : + (exc.hasTag(CLASS)) ? isUnchecked((ClassSymbol)exc.tsym) : + exc.hasTag(BOT); + } + + /** Same, but handling completion failures. + */ + boolean isUnchecked(DiagnosticPosition pos, Type exc) { + try { + return isUnchecked(exc); + } catch (CompletionFailure ex) { + completionError(pos, ex); + return true; + } + } + + /** Is exc handled by given exception list? + */ + boolean isHandled(Type exc, List handled) { + return isUnchecked(exc) || subset(exc, handled); + } + + /** Return all exceptions in thrown list that are not in handled list. + * @param thrown The list of thrown exceptions. + * @param handled The list of handled exceptions. + */ + List unhandled(List thrown, List handled) { + List unhandled = List.nil(); + for (List l = thrown; l.nonEmpty(); l = l.tail) + if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head); + return unhandled; + } + +/* ************************************************************************* + * Overriding/Implementation checking + **************************************************************************/ + + /** The level of access protection given by a flag set, + * where PRIVATE is highest and PUBLIC is lowest. + */ + static int protection(long flags) { + switch ((short)(flags & AccessFlags)) { + case PRIVATE: return 3; + case PROTECTED: return 1; + default: + case PUBLIC: return 0; + case 0: return 2; + } + } + + /** A customized "cannot override" error message. + * @param m The overriding method. + * @param other The overridden method. + * @return An internationalized string. + */ + Object cannotOverride(MethodSymbol m, MethodSymbol other) { + String key; + if ((other.owner.flags() & INTERFACE) == 0) + key = "cant.override"; + else if ((m.owner.flags() & INTERFACE) == 0) + key = "cant.implement"; + else + key = "clashes.with"; + return diags.fragment(key, m, m.location(), other, other.location()); + } + + /** A customized "override" warning message. + * @param m The overriding method. + * @param other The overridden method. + * @return An internationalized string. + */ + Object uncheckedOverrides(MethodSymbol m, MethodSymbol other) { + String key; + if ((other.owner.flags() & INTERFACE) == 0) + key = "unchecked.override"; + else if ((m.owner.flags() & INTERFACE) == 0) + key = "unchecked.implement"; + else + key = "unchecked.clash.with"; + return diags.fragment(key, m, m.location(), other, other.location()); + } + + /** A customized "override" warning message. + * @param m The overriding method. + * @param other The overridden method. + * @return An internationalized string. + */ + Object varargsOverrides(MethodSymbol m, MethodSymbol other) { + String key; + if ((other.owner.flags() & INTERFACE) == 0) + key = "varargs.override"; + else if ((m.owner.flags() & INTERFACE) == 0) + key = "varargs.implement"; + else + key = "varargs.clash.with"; + return diags.fragment(key, m, m.location(), other, other.location()); + } + + /** Check that this method conforms with overridden method 'other'. + * where `origin' is the class where checking started. + * Complications: + * (1) Do not check overriding of synthetic methods + * (reason: they might be final). + * todo: check whether this is still necessary. + * (2) Admit the case where an interface proxy throws fewer exceptions + * than the method it implements. Augment the proxy methods with the + * undeclared exceptions in this case. + * (3) When generics are enabled, admit the case where an interface proxy + * has a result type + * extended by the result type of the method it implements. + * Change the proxies result type to the smaller type in this case. + * + * @param tree The tree from which positions + * are extracted for errors. + * @param m The overriding method. + * @param other The overridden method. + * @param origin The class of which the overriding method + * is a member. + */ + void checkOverride(JCTree tree, + MethodSymbol m, + MethodSymbol other, + ClassSymbol origin) { + // Don't check overriding of synthetic methods or by bridge methods. + if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) { + return; + } + + // Error if static method overrides instance method (JLS 8.4.6.2). + if ((m.flags() & STATIC) != 0 && + (other.flags() & STATIC) == 0) { + log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.static", + cannotOverride(m, other)); + m.flags_field |= BAD_OVERRIDE; + return; + } + + // Error if instance method overrides static or final + // method (JLS 8.4.6.1). + if ((other.flags() & FINAL) != 0 || + (m.flags() & STATIC) == 0 && + (other.flags() & STATIC) != 0) { + log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.meth", + cannotOverride(m, other), + asFlagSet(other.flags() & (FINAL | STATIC))); + m.flags_field |= BAD_OVERRIDE; + return; + } + + if ((m.owner.flags() & ANNOTATION) != 0) { + // handled in validateAnnotationMethod + return; + } + + // Error if overriding method has weaker access (JLS 8.4.6.3). + if ((origin.flags() & INTERFACE) == 0 && + protection(m.flags()) > protection(other.flags())) { + log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.weaker.access", + cannotOverride(m, other), + other.flags() == 0 ? + "package" : + asFlagSet(other.flags() & AccessFlags)); + m.flags_field |= BAD_OVERRIDE; + return; + } + + Type mt = types.memberType(origin.type, m); + Type ot = types.memberType(origin.type, other); + // Error if overriding result type is different + // (or, in the case of generics mode, not a subtype) of + // overridden result type. We have to rename any type parameters + // before comparing types. + List mtvars = mt.getTypeArguments(); + List otvars = ot.getTypeArguments(); + Type mtres = mt.getReturnType(); + Type otres = types.subst(ot.getReturnType(), otvars, mtvars); + + overrideWarner.clear(); + boolean resultTypesOK = + types.returnTypeSubstitutable(mt, ot, otres, overrideWarner); + if (!resultTypesOK) { + if (!allowCovariantReturns && + m.owner != origin && + m.owner.isSubClass(other.owner, types)) { + // allow limited interoperability with covariant returns + } else { + log.error(TreeInfo.diagnosticPositionFor(m, tree), + "override.incompatible.ret", + cannotOverride(m, other), + mtres, otres); + m.flags_field |= BAD_OVERRIDE; + return; + } + } else if (overrideWarner.hasNonSilentLint(LintCategory.UNCHECKED)) { + warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree), + "override.unchecked.ret", + uncheckedOverrides(m, other), + mtres, otres); + } + + // Error if overriding method throws an exception not reported + // by overridden method. + List otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars); + List unhandledErased = unhandled(mt.getThrownTypes(), types.erasure(otthrown)); + List unhandledUnerased = unhandled(mt.getThrownTypes(), otthrown); + if (unhandledErased.nonEmpty()) { + log.error(TreeInfo.diagnosticPositionFor(m, tree), + "override.meth.doesnt.throw", + cannotOverride(m, other), + unhandledUnerased.head); + m.flags_field |= BAD_OVERRIDE; + return; + } + else if (unhandledUnerased.nonEmpty()) { + warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree), + "override.unchecked.thrown", + cannotOverride(m, other), + unhandledUnerased.head); + return; + } + + // Optional warning if varargs don't agree + if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0) + && lint.isEnabled(LintCategory.OVERRIDES)) { + log.warning(TreeInfo.diagnosticPositionFor(m, tree), + ((m.flags() & Flags.VARARGS) != 0) + ? "override.varargs.missing" + : "override.varargs.extra", + varargsOverrides(m, other)); + } + + // Warn if instance method overrides bridge method (compiler spec ??) + if ((other.flags() & BRIDGE) != 0) { + log.warning(TreeInfo.diagnosticPositionFor(m, tree), "override.bridge", + uncheckedOverrides(m, other)); + } + + // Warn if a deprecated method overridden by a non-deprecated one. + if (!isDeprecatedOverrideIgnorable(other, origin)) { + checkDeprecated(TreeInfo.diagnosticPositionFor(m, tree), m, other); + } + } + // where + private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) { + // If the method, m, is defined in an interface, then ignore the issue if the method + // is only inherited via a supertype and also implemented in the supertype, + // because in that case, we will rediscover the issue when examining the method + // in the supertype. + // If the method, m, is not defined in an interface, then the only time we need to + // address the issue is when the method is the supertype implemementation: any other + // case, we will have dealt with when examining the supertype classes + ClassSymbol mc = m.enclClass(); + Type st = types.supertype(origin.type); + if (!st.hasTag(CLASS)) + return true; + MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false); + + if (mc != null && ((mc.flags() & INTERFACE) != 0)) { + List intfs = types.interfaces(origin.type); + return (intfs.contains(mc.type) ? false : (stimpl != null)); + } + else + return (stimpl != m); + } + + + // used to check if there were any unchecked conversions + Warner overrideWarner = new Warner(); + + /** Check that a class does not inherit two concrete methods + * with the same signature. + * @param pos Position to be used for error reporting. + * @param site The class type to be checked. + */ + public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) { + Type sup = types.supertype(site); + if (!sup.hasTag(CLASS)) return; + + for (Type t1 = sup; + t1.hasTag(CLASS) && t1.tsym.type.isParameterized(); + t1 = types.supertype(t1)) { + for (Scope.Entry e1 = t1.tsym.members().elems; + e1 != null; + e1 = e1.sibling) { + Symbol s1 = e1.sym; + if (s1.kind != MTH || + (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 || + !s1.isInheritedIn(site.tsym, types) || + ((MethodSymbol)s1).implementation(site.tsym, + types, + true) != s1) + continue; + Type st1 = types.memberType(t1, s1); + int s1ArgsLength = st1.getParameterTypes().length(); + if (st1 == s1.type) continue; + + for (Type t2 = sup; + t2.hasTag(CLASS); + t2 = types.supertype(t2)) { + for (Scope.Entry e2 = t2.tsym.members().lookup(s1.name); + e2.scope != null; + e2 = e2.next()) { + Symbol s2 = e2.sym; + if (s2 == s1 || + s2.kind != MTH || + (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 || + s2.type.getParameterTypes().length() != s1ArgsLength || + !s2.isInheritedIn(site.tsym, types) || + ((MethodSymbol)s2).implementation(site.tsym, + types, + true) != s2) + continue; + Type st2 = types.memberType(t2, s2); + if (types.overrideEquivalent(st1, st2)) + log.error(pos, "concrete.inheritance.conflict", + s1, t1, s2, t2, sup); + } + } + } + } + } + + /** Check that classes (or interfaces) do not each define an abstract + * method with same name and arguments but incompatible return types. + * @param pos Position to be used for error reporting. + * @param t1 The first argument type. + * @param t2 The second argument type. + */ + public boolean checkCompatibleAbstracts(DiagnosticPosition pos, + Type t1, + Type t2) { + return checkCompatibleAbstracts(pos, t1, t2, + types.makeCompoundType(t1, t2)); + } + + public boolean checkCompatibleAbstracts(DiagnosticPosition pos, + Type t1, + Type t2, + Type site) { + if ((site.tsym.flags() & COMPOUND) != 0) { + // special case for intersections: need to eliminate wildcards in supertypes + t1 = types.capture(t1); + t2 = types.capture(t2); + } + return firstIncompatibility(pos, t1, t2, site) == null; + } + + /** Return the first method which is defined with same args + * but different return types in two given interfaces, or null if none + * exists. + * @param t1 The first type. + * @param t2 The second type. + * @param site The most derived type. + * @returns symbol from t2 that conflicts with one in t1. + */ + private Symbol firstIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) { + Map interfaces1 = new HashMap(); + closure(t1, interfaces1); + Map interfaces2; + if (t1 == t2) + interfaces2 = interfaces1; + else + closure(t2, interfaces1, interfaces2 = new HashMap()); + + for (Type t3 : interfaces1.values()) { + for (Type t4 : interfaces2.values()) { + Symbol s = firstDirectIncompatibility(pos, t3, t4, site); + if (s != null) return s; + } + } + return null; + } + + /** Compute all the supertypes of t, indexed by type symbol. */ + private void closure(Type t, Map typeMap) { + if (!t.hasTag(CLASS)) return; + if (typeMap.put(t.tsym, t) == null) { + closure(types.supertype(t), typeMap); + for (Type i : types.interfaces(t)) + closure(i, typeMap); + } + } + + /** Compute all the supertypes of t, indexed by type symbol (except thise in typesSkip). */ + private void closure(Type t, Map typesSkip, Map typeMap) { + if (!t.hasTag(CLASS)) return; + if (typesSkip.get(t.tsym) != null) return; + if (typeMap.put(t.tsym, t) == null) { + closure(types.supertype(t), typesSkip, typeMap); + for (Type i : types.interfaces(t)) + closure(i, typesSkip, typeMap); + } + } + + /** Return the first method in t2 that conflicts with a method from t1. */ + private Symbol firstDirectIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) { + for (Scope.Entry e1 = t1.tsym.members().elems; e1 != null; e1 = e1.sibling) { + Symbol s1 = e1.sym; + Type st1 = null; + if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types) || + (s1.flags() & SYNTHETIC) != 0) continue; + Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false); + if (impl != null && (impl.flags() & ABSTRACT) == 0) continue; + for (Scope.Entry e2 = t2.tsym.members().lookup(s1.name); e2.scope != null; e2 = e2.next()) { + Symbol s2 = e2.sym; + if (s1 == s2) continue; + if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types) || + (s2.flags() & SYNTHETIC) != 0) continue; + if (st1 == null) st1 = types.memberType(t1, s1); + Type st2 = types.memberType(t2, s2); + if (types.overrideEquivalent(st1, st2)) { + List tvars1 = st1.getTypeArguments(); + List tvars2 = st2.getTypeArguments(); + Type rt1 = st1.getReturnType(); + Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1); + boolean compat = + types.isSameType(rt1, rt2) || + !rt1.isPrimitiveOrVoid() && + !rt2.isPrimitiveOrVoid() && + (types.covariantReturnType(rt1, rt2, types.noWarnings) || + types.covariantReturnType(rt2, rt1, types.noWarnings)) || + checkCommonOverriderIn(s1,s2,site); + if (!compat) { + log.error(pos, "types.incompatible.diff.ret", + t1, t2, s2.name + + "(" + types.memberType(t2, s2).getParameterTypes() + ")"); + return s2; + } + } else if (checkNameClash((ClassSymbol)site.tsym, s1, s2) && + !checkCommonOverriderIn(s1, s2, site)) { + log.error(pos, + "name.clash.same.erasure.no.override", + s1, s1.location(), + s2, s2.location()); + return s2; + } + } + } + return null; + } + //WHERE + boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) { + Map supertypes = new HashMap(); + Type st1 = types.memberType(site, s1); + Type st2 = types.memberType(site, s2); + closure(site, supertypes); + for (Type t : supertypes.values()) { + for (Scope.Entry e = t.tsym.members().lookup(s1.name); e.scope != null; e = e.next()) { + Symbol s3 = e.sym; + if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue; + Type st3 = types.memberType(site,s3); + if (types.overrideEquivalent(st3, st1) && + types.overrideEquivalent(st3, st2) && + types.returnTypeSubstitutable(st3, st1) && + types.returnTypeSubstitutable(st3, st2)) { + return true; + } + } + } + return false; + } + + /** Check that a given method conforms with any method it overrides. + * @param tree The tree from which positions are extracted + * for errors. + * @param m The overriding method. + */ + void checkOverride(JCMethodDecl tree, MethodSymbol m) { + ClassSymbol origin = (ClassSymbol)m.owner; + if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name)) + if (m.overrides(syms.enumFinalFinalize, origin, types, false)) { + log.error(tree.pos(), "enum.no.finalize"); + return; + } + for (Type t = origin.type; t.hasTag(CLASS); + t = types.supertype(t)) { + if (t != origin.type) { + checkOverride(tree, t, origin, m); + } + for (Type t2 : types.interfaces(t)) { + checkOverride(tree, t2, origin, m); + } + } + + if (m.attribute(syms.overrideType.tsym) != null && !isOverrider(m)) { + DiagnosticPosition pos = tree.pos(); + for (JCAnnotation a : tree.getModifiers().annotations) { + if (a.annotationType.type.tsym == syms.overrideType.tsym) { + pos = a.pos(); + break; + } + } + log.error(pos, "method.does.not.override.superclass"); + } + } + + void checkOverride(JCTree tree, Type site, ClassSymbol origin, MethodSymbol m) { + TypeSymbol c = site.tsym; + Scope.Entry e = c.members().lookup(m.name); + while (e.scope != null) { + if (m.overrides(e.sym, origin, types, false)) { + if ((e.sym.flags() & ABSTRACT) == 0) { + checkOverride(tree, m, (MethodSymbol)e.sym, origin); + } + } + e = e.next(); + } + } + + private Filter equalsHasCodeFilter = new Filter() { + public boolean accepts(Symbol s) { + return MethodSymbol.implementation_filter.accepts(s) && + (s.flags() & BAD_OVERRIDE) == 0; + + } + }; + + public void checkClassOverrideEqualsAndHashIfNeeded(DiagnosticPosition pos, + ClassSymbol someClass) { + /* At present, annotations cannot possibly have a method that is override + * equivalent with Object.equals(Object) but in any case the condition is + * fine for completeness. + */ + if (someClass == (ClassSymbol)syms.objectType.tsym || + someClass.isInterface() || someClass.isEnum() || + (someClass.flags() & ANNOTATION) != 0 || + (someClass.flags() & ABSTRACT) != 0) return; + //anonymous inner classes implementing interfaces need especial treatment + if (someClass.isAnonymous()) { + List interfaces = types.interfaces(someClass.type); + if (interfaces != null && !interfaces.isEmpty() && + interfaces.head.tsym == syms.comparatorType.tsym) return; + } + checkClassOverrideEqualsAndHash(pos, someClass); + } + + private void checkClassOverrideEqualsAndHash(DiagnosticPosition pos, + ClassSymbol someClass) { + if (lint.isEnabled(LintCategory.OVERRIDES)) { + MethodSymbol equalsAtObject = (MethodSymbol)syms.objectType + .tsym.members().lookup(names.equals).sym; + MethodSymbol hashCodeAtObject = (MethodSymbol)syms.objectType + .tsym.members().lookup(names.hashCode).sym; + boolean overridesEquals = types.implementation(equalsAtObject, + someClass, false, equalsHasCodeFilter).owner == someClass; + boolean overridesHashCode = types.implementation(hashCodeAtObject, + someClass, false, equalsHasCodeFilter) != hashCodeAtObject; + + if (overridesEquals && !overridesHashCode) { + log.warning(LintCategory.OVERRIDES, pos, + "override.equals.but.not.hashcode", someClass); + } + } + } + + private boolean checkNameClash(ClassSymbol origin, Symbol s1, Symbol s2) { + ClashFilter cf = new ClashFilter(origin.type); + return (cf.accepts(s1) && + cf.accepts(s2) && + types.hasSameArgs(s1.erasure(types), s2.erasure(types))); + } + + + /** Check that all abstract members of given class have definitions. + * @param pos Position to be used for error reporting. + * @param c The class. + */ + void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) { + try { + MethodSymbol undef = firstUndef(c, c); + if (undef != null) { + if ((c.flags() & ENUM) != 0 && + types.supertype(c.type).tsym == syms.enumSym && + (c.flags() & FINAL) == 0) { + // add the ABSTRACT flag to an enum + c.flags_field |= ABSTRACT; + } else { + MethodSymbol undef1 = + new MethodSymbol(undef.flags(), undef.name, + types.memberType(c.type, undef), undef.owner); + log.error(pos, "does.not.override.abstract", + c, undef1, undef1.location()); + } + } + } catch (CompletionFailure ex) { + completionError(pos, ex); + } + } +//where + /** Return first abstract member of class `c' that is not defined + * in `impl', null if there is none. + */ + private MethodSymbol firstUndef(ClassSymbol impl, ClassSymbol c) { + MethodSymbol undef = null; + // Do not bother to search in classes that are not abstract, + // since they cannot have abstract members. + if (c == impl || (c.flags() & (ABSTRACT | INTERFACE)) != 0) { + Scope s = c.members(); + for (Scope.Entry e = s.elems; + undef == null && e != null; + e = e.sibling) { + if (e.sym.kind == MTH && + (e.sym.flags() & (ABSTRACT|IPROXY|DEFAULT)) == ABSTRACT) { + MethodSymbol absmeth = (MethodSymbol)e.sym; + MethodSymbol implmeth = absmeth.implementation(impl, types, true); + if (implmeth == null || implmeth == absmeth) { + //look for default implementations + if (allowDefaultMethods) { + MethodSymbol prov = types.interfaceCandidates(impl.type, absmeth).head; + if (prov != null && prov.overrides(absmeth, impl, types, true)) { + implmeth = prov; + } + } + } + if (implmeth == null || implmeth == absmeth) { + undef = absmeth; + } + } + } + if (undef == null) { + Type st = types.supertype(c.type); + if (st.hasTag(CLASS)) + undef = firstUndef(impl, (ClassSymbol)st.tsym); + } + for (List l = types.interfaces(c.type); + undef == null && l.nonEmpty(); + l = l.tail) { + undef = firstUndef(impl, (ClassSymbol)l.head.tsym); + } + } + return undef; + } + + void checkNonCyclicDecl(JCClassDecl tree) { + CycleChecker cc = new CycleChecker(); + cc.scan(tree); + if (!cc.errorFound && !cc.partialCheck) { + tree.sym.flags_field |= ACYCLIC; + } + } + + class CycleChecker extends TreeScanner { + + List seenClasses = List.nil(); + boolean errorFound = false; + boolean partialCheck = false; + + private void checkSymbol(DiagnosticPosition pos, Symbol sym) { + if (sym != null && sym.kind == TYP) { + Env classEnv = enter.getEnv((TypeSymbol)sym); + if (classEnv != null) { + DiagnosticSource prevSource = log.currentSource(); + try { + log.useSource(classEnv.toplevel.sourcefile); + scan(classEnv.tree); + } + finally { + log.useSource(prevSource.getFile()); + } + } else if (sym.kind == TYP) { + checkClass(pos, sym, List.nil()); + } + } else { + //not completed yet + partialCheck = true; + } + } + + @Override + public void visitSelect(JCFieldAccess tree) { + super.visitSelect(tree); + checkSymbol(tree.pos(), tree.sym); + } + + @Override + public void visitIdent(JCIdent tree) { + checkSymbol(tree.pos(), tree.sym); + } + + @Override + public void visitTypeApply(JCTypeApply tree) { + scan(tree.clazz); + } + + @Override + public void visitTypeArray(JCArrayTypeTree tree) { + scan(tree.elemtype); + } + + @Override + public void visitClassDef(JCClassDecl tree) { + List supertypes = List.nil(); + if (tree.getExtendsClause() != null) { + supertypes = supertypes.prepend(tree.getExtendsClause()); + } + if (tree.getImplementsClause() != null) { + for (JCTree intf : tree.getImplementsClause()) { + supertypes = supertypes.prepend(intf); + } + } + checkClass(tree.pos(), tree.sym, supertypes); + } + + void checkClass(DiagnosticPosition pos, Symbol c, List supertypes) { + if ((c.flags_field & ACYCLIC) != 0) + return; + if (seenClasses.contains(c)) { + errorFound = true; + noteCyclic(pos, (ClassSymbol)c); + } else if (!c.type.isErroneous()) { + try { + seenClasses = seenClasses.prepend(c); + if (c.type.hasTag(CLASS)) { + if (supertypes.nonEmpty()) { + scan(supertypes); + } + else { + ClassType ct = (ClassType)c.type; + if (ct.supertype_field == null || + ct.interfaces_field == null) { + //not completed yet + partialCheck = true; + return; + } + checkSymbol(pos, ct.supertype_field.tsym); + for (Type intf : ct.interfaces_field) { + checkSymbol(pos, intf.tsym); + } + } + if (c.owner.kind == TYP) { + checkSymbol(pos, c.owner); + } + } + } finally { + seenClasses = seenClasses.tail; + } + } + } + } + + /** Check for cyclic references. Issue an error if the + * symbol of the type referred to has a LOCKED flag set. + * + * @param pos Position to be used for error reporting. + * @param t The type referred to. + */ + void checkNonCyclic(DiagnosticPosition pos, Type t) { + checkNonCyclicInternal(pos, t); + } + + + void checkNonCyclic(DiagnosticPosition pos, TypeVar t) { + checkNonCyclic1(pos, t, List.nil()); + } + + private void checkNonCyclic1(DiagnosticPosition pos, Type t, List seen) { + final TypeVar tv; + if (t.hasTag(TYPEVAR) && (t.tsym.flags() & UNATTRIBUTED) != 0) + return; + if (seen.contains(t)) { + tv = (TypeVar)t.unannotatedType(); + tv.bound = types.createErrorType(t); + log.error(pos, "cyclic.inheritance", t); + } else if (t.hasTag(TYPEVAR)) { + tv = (TypeVar)t.unannotatedType(); + seen = seen.prepend(tv); + for (Type b : types.getBounds(tv)) + checkNonCyclic1(pos, b, seen); + } + } + + /** Check for cyclic references. Issue an error if the + * symbol of the type referred to has a LOCKED flag set. + * + * @param pos Position to be used for error reporting. + * @param t The type referred to. + * @returns True if the check completed on all attributed classes + */ + private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) { + boolean complete = true; // was the check complete? + //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG + Symbol c = t.tsym; + if ((c.flags_field & ACYCLIC) != 0) return true; + + if ((c.flags_field & LOCKED) != 0) { + noteCyclic(pos, (ClassSymbol)c); + } else if (!c.type.isErroneous()) { + try { + c.flags_field |= LOCKED; + if (c.type.hasTag(CLASS)) { + ClassType clazz = (ClassType)c.type; + if (clazz.interfaces_field != null) + for (List l=clazz.interfaces_field; l.nonEmpty(); l=l.tail) + complete &= checkNonCyclicInternal(pos, l.head); + if (clazz.supertype_field != null) { + Type st = clazz.supertype_field; + if (st != null && st.hasTag(CLASS)) + complete &= checkNonCyclicInternal(pos, st); + } + if (c.owner.kind == TYP) + complete &= checkNonCyclicInternal(pos, c.owner.type); + } + } finally { + c.flags_field &= ~LOCKED; + } + } + if (complete) + complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.completer == null; + if (complete) c.flags_field |= ACYCLIC; + return complete; + } + + /** Note that we found an inheritance cycle. */ + private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) { + log.error(pos, "cyclic.inheritance", c); + for (List l=types.interfaces(c.type); l.nonEmpty(); l=l.tail) + l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType); + Type st = types.supertype(c.type); + if (st.hasTag(CLASS)) + ((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType); + c.type = types.createErrorType(c, c.type); + c.flags_field |= ACYCLIC; + } + + /** Check that all methods which implement some + * method conform to the method they implement. + * @param tree The class definition whose members are checked. + */ + void checkImplementations(JCClassDecl tree) { + checkImplementations(tree, tree.sym, tree.sym); + } + //where + /** Check that all methods which implement some + * method in `ic' conform to the method they implement. + */ + void checkImplementations(JCTree tree, ClassSymbol origin, ClassSymbol ic) { + for (List l = types.closure(ic.type); l.nonEmpty(); l = l.tail) { + ClassSymbol lc = (ClassSymbol)l.head.tsym; + if ((allowGenerics || origin != lc) && (lc.flags() & ABSTRACT) != 0) { + for (Scope.Entry e=lc.members().elems; e != null; e=e.sibling) { + if (e.sym.kind == MTH && + (e.sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) { + MethodSymbol absmeth = (MethodSymbol)e.sym; + MethodSymbol implmeth = absmeth.implementation(origin, types, false); + if (implmeth != null && implmeth != absmeth && + (implmeth.owner.flags() & INTERFACE) == + (origin.flags() & INTERFACE)) { + // don't check if implmeth is in a class, yet + // origin is an interface. This case arises only + // if implmeth is declared in Object. The reason is + // that interfaces really don't inherit from + // Object it's just that the compiler represents + // things that way. + checkOverride(tree, implmeth, absmeth, origin); + } + } + } + } + } + } + + /** Check that all abstract methods implemented by a class are + * mutually compatible. + * @param pos Position to be used for error reporting. + * @param c The class whose interfaces are checked. + */ + void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) { + List supertypes = types.interfaces(c); + Type supertype = types.supertype(c); + if (supertype.hasTag(CLASS) && + (supertype.tsym.flags() & ABSTRACT) != 0) + supertypes = supertypes.prepend(supertype); + for (List l = supertypes; l.nonEmpty(); l = l.tail) { + if (allowGenerics && !l.head.getTypeArguments().isEmpty() && + !checkCompatibleAbstracts(pos, l.head, l.head, c)) + return; + for (List m = supertypes; m != l; m = m.tail) + if (!checkCompatibleAbstracts(pos, l.head, m.head, c)) + return; + } + checkCompatibleConcretes(pos, c); + } + + void checkConflicts(DiagnosticPosition pos, Symbol sym, TypeSymbol c) { + for (Type ct = c.type; ct != Type.noType ; ct = types.supertype(ct)) { + for (Scope.Entry e = ct.tsym.members().lookup(sym.name); e.scope == ct.tsym.members(); e = e.next()) { + // VM allows methods and variables with differing types + if (sym.kind == e.sym.kind && + types.isSameType(types.erasure(sym.type), types.erasure(e.sym.type)) && + sym != e.sym && + (sym.flags() & Flags.SYNTHETIC) != (e.sym.flags() & Flags.SYNTHETIC) && + (sym.flags() & IPROXY) == 0 && (e.sym.flags() & IPROXY) == 0 && + (sym.flags() & BRIDGE) == 0 && (e.sym.flags() & BRIDGE) == 0) { + syntheticError(pos, (e.sym.flags() & SYNTHETIC) == 0 ? e.sym : sym); + return; + } + } + } + } + + /** Check that all non-override equivalent methods accessible from 'site' + * are mutually compatible (JLS 8.4.8/9.4.1). + * + * @param pos Position to be used for error reporting. + * @param site The class whose methods are checked. + * @param sym The method symbol to be checked. + */ + void checkOverrideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) { + ClashFilter cf = new ClashFilter(site); + //for each method m1 that is overridden (directly or indirectly) + //by method 'sym' in 'site'... + + List potentiallyAmbiguousList = List.nil(); + boolean overridesAny = false; + for (Symbol m1 : types.membersClosure(site, false).getElementsByName(sym.name, cf)) { + if (!sym.overrides(m1, site.tsym, types, false)) { + if (m1 == sym) { + continue; + } + + if (!overridesAny) { + potentiallyAmbiguousList = potentiallyAmbiguousList.prepend((MethodSymbol)m1); + } + continue; + } + + if (m1 != sym) { + overridesAny = true; + potentiallyAmbiguousList = List.nil(); + } + + //...check each method m2 that is a member of 'site' + for (Symbol m2 : types.membersClosure(site, false).getElementsByName(sym.name, cf)) { + if (m2 == m1) continue; + //if (i) the signature of 'sym' is not a subsignature of m1 (seen as + //a member of 'site') and (ii) m1 has the same erasure as m2, issue an error + if (!types.isSubSignature(sym.type, types.memberType(site, m2), allowStrictMethodClashCheck) && + types.hasSameArgs(m2.erasure(types), m1.erasure(types))) { + sym.flags_field |= CLASH; + String key = m1 == sym ? + "name.clash.same.erasure.no.override" : + "name.clash.same.erasure.no.override.1"; + log.error(pos, + key, + sym, sym.location(), + m2, m2.location(), + m1, m1.location()); + return; + } + } + } + + if (!overridesAny) { + for (MethodSymbol m: potentiallyAmbiguousList) { + checkPotentiallyAmbiguousOverloads(pos, site, sym, m); + } + } + } + + /** Check that all static methods accessible from 'site' are + * mutually compatible (JLS 8.4.8). + * + * @param pos Position to be used for error reporting. + * @param site The class whose methods are checked. + * @param sym The method symbol to be checked. + */ + void checkHideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) { + ClashFilter cf = new ClashFilter(site); + //for each method m1 that is a member of 'site'... + for (Symbol s : types.membersClosure(site, true).getElementsByName(sym.name, cf)) { + //if (i) the signature of 'sym' is not a subsignature of m1 (seen as + //a member of 'site') and (ii) 'sym' has the same erasure as m1, issue an error + if (!types.isSubSignature(sym.type, types.memberType(site, s), allowStrictMethodClashCheck)) { + if (types.hasSameArgs(s.erasure(types), sym.erasure(types))) { + log.error(pos, + "name.clash.same.erasure.no.hide", + sym, sym.location(), + s, s.location()); + return; + } else { + checkPotentiallyAmbiguousOverloads(pos, site, sym, (MethodSymbol)s); + } + } + } + } + + //where + private class ClashFilter implements Filter { + + Type site; + + ClashFilter(Type site) { + this.site = site; + } + + boolean shouldSkip(Symbol s) { + return (s.flags() & CLASH) != 0 && + s.owner == site.tsym; + } + + public boolean accepts(Symbol s) { + return s.kind == MTH && + (s.flags() & SYNTHETIC) == 0 && + !shouldSkip(s) && + s.isInheritedIn(site.tsym, types) && + !s.isConstructor(); + } + } + + void checkDefaultMethodClashes(DiagnosticPosition pos, Type site) { + DefaultMethodClashFilter dcf = new DefaultMethodClashFilter(site); + for (Symbol m : types.membersClosure(site, false).getElements(dcf)) { + Assert.check(m.kind == MTH); + List prov = types.interfaceCandidates(site, (MethodSymbol)m); + if (prov.size() > 1) { + ListBuffer abstracts = new ListBuffer<>(); + ListBuffer defaults = new ListBuffer<>(); + for (MethodSymbol provSym : prov) { + if ((provSym.flags() & DEFAULT) != 0) { + defaults = defaults.append(provSym); + } else if ((provSym.flags() & ABSTRACT) != 0) { + abstracts = abstracts.append(provSym); + } + if (defaults.nonEmpty() && defaults.size() + abstracts.size() >= 2) { + //strong semantics - issue an error if two sibling interfaces + //have two override-equivalent defaults - or if one is abstract + //and the other is default + String errKey; + Symbol s1 = defaults.first(); + Symbol s2; + if (defaults.size() > 1) { + errKey = "types.incompatible.unrelated.defaults"; + s2 = defaults.toList().tail.head; + } else { + errKey = "types.incompatible.abstract.default"; + s2 = abstracts.first(); + } + log.error(pos, errKey, + Kinds.kindName(site.tsym), site, + m.name, types.memberType(site, m).getParameterTypes(), + s1.location(), s2.location()); + break; + } + } + } + } + } + + //where + private class DefaultMethodClashFilter implements Filter { + + Type site; + + DefaultMethodClashFilter(Type site) { + this.site = site; + } + + public boolean accepts(Symbol s) { + return s.kind == MTH && + (s.flags() & DEFAULT) != 0 && + s.isInheritedIn(site.tsym, types) && + !s.isConstructor(); + } + } + + /** + * Report warnings for potentially ambiguous method declarations. Two declarations + * are potentially ambiguous if they feature two unrelated functional interface + * in same argument position (in which case, a call site passing an implicit + * lambda would be ambiguous). + */ + void checkPotentiallyAmbiguousOverloads(DiagnosticPosition pos, Type site, + MethodSymbol msym1, MethodSymbol msym2) { + if (msym1 != msym2 && + allowDefaultMethods && + lint.isEnabled(LintCategory.OVERLOADS) && + (msym1.flags() & POTENTIALLY_AMBIGUOUS) == 0 && + (msym2.flags() & POTENTIALLY_AMBIGUOUS) == 0) { + Type mt1 = types.memberType(site, msym1); + Type mt2 = types.memberType(site, msym2); + //if both generic methods, adjust type variables + if (mt1.hasTag(FORALL) && mt2.hasTag(FORALL) && + types.hasSameBounds((ForAll)mt1, (ForAll)mt2)) { + mt2 = types.subst(mt2, ((ForAll)mt2).tvars, ((ForAll)mt1).tvars); + } + //expand varargs methods if needed + int maxLength = Math.max(mt1.getParameterTypes().length(), mt2.getParameterTypes().length()); + List args1 = rs.adjustArgs(mt1.getParameterTypes(), msym1, maxLength, true); + List args2 = rs.adjustArgs(mt2.getParameterTypes(), msym2, maxLength, true); + //if arities don't match, exit + if (args1.length() != args2.length()) return; + boolean potentiallyAmbiguous = false; + while (args1.nonEmpty() && args2.nonEmpty()) { + Type s = args1.head; + Type t = args2.head; + if (!types.isSubtype(t, s) && !types.isSubtype(s, t)) { + if (types.isFunctionalInterface(s) && types.isFunctionalInterface(t) && + types.findDescriptorType(s).getParameterTypes().length() > 0 && + types.findDescriptorType(s).getParameterTypes().length() == + types.findDescriptorType(t).getParameterTypes().length()) { + potentiallyAmbiguous = true; + } else { + break; + } + } + args1 = args1.tail; + args2 = args2.tail; + } + if (potentiallyAmbiguous) { + //we found two incompatible functional interfaces with same arity + //this means a call site passing an implicit lambda would be ambigiuous + msym1.flags_field |= POTENTIALLY_AMBIGUOUS; + msym2.flags_field |= POTENTIALLY_AMBIGUOUS; + log.warning(LintCategory.OVERLOADS, pos, "potentially.ambiguous.overload", + msym1, msym1.location(), + msym2, msym2.location()); + return; + } + } + } + + void checkElemAccessFromSerializableLambda(final JCTree tree) { + if (warnOnAccessToSensitiveMembers) { + Symbol sym = TreeInfo.symbol(tree); + if ((sym.kind & (VAR | MTH)) == 0) { + return; + } + + if (sym.kind == VAR) { + if ((sym.flags() & PARAMETER) != 0 || + sym.isLocal() || + sym.name == names._this || + sym.name == names._super) { + return; + } + } + + if (!types.isSubtype(sym.owner.type, syms.serializableType) && + isEffectivelyNonPublic(sym)) { + log.warning(tree.pos(), + "access.to.sensitive.member.from.serializable.element", sym); + } + } + } + + private boolean isEffectivelyNonPublic(Symbol sym) { + if (sym.packge() == syms.rootPackage) { + return false; + } + + while (sym.kind != Kinds.PCK) { + if ((sym.flags() & PUBLIC) == 0) { + return true; + } + sym = sym.owner; + } + return false; + } + + /** Report a conflict between a user symbol and a synthetic symbol. + */ + private void syntheticError(DiagnosticPosition pos, Symbol sym) { + if (!sym.type.isErroneous()) { + if (warnOnSyntheticConflicts) { + log.warning(pos, "synthetic.name.conflict", sym, sym.location()); + } + else { + log.error(pos, "synthetic.name.conflict", sym, sym.location()); + } + } + } + + /** Check that class c does not implement directly or indirectly + * the same parameterized interface with two different argument lists. + * @param pos Position to be used for error reporting. + * @param type The type whose interfaces are checked. + */ + void checkClassBounds(DiagnosticPosition pos, Type type) { + checkClassBounds(pos, new HashMap(), type); + } +//where + /** Enter all interfaces of type `type' into the hash table `seensofar' + * with their class symbol as key and their type as value. Make + * sure no class is entered with two different types. + */ + void checkClassBounds(DiagnosticPosition pos, + Map seensofar, + Type type) { + if (type.isErroneous()) return; + for (List l = types.interfaces(type); l.nonEmpty(); l = l.tail) { + Type it = l.head; + Type oldit = seensofar.put(it.tsym, it); + if (oldit != null) { + List oldparams = oldit.allparams(); + List newparams = it.allparams(); + if (!types.containsTypeEquivalent(oldparams, newparams)) + log.error(pos, "cant.inherit.diff.arg", + it.tsym, Type.toString(oldparams), + Type.toString(newparams)); + } + checkClassBounds(pos, seensofar, it); + } + Type st = types.supertype(type); + if (st != Type.noType) checkClassBounds(pos, seensofar, st); + } + + /** Enter interface into into set. + * If it existed already, issue a "repeated interface" error. + */ + void checkNotRepeated(DiagnosticPosition pos, Type it, Set its) { + if (its.contains(it)) + log.error(pos, "repeated.interface"); + else { + its.add(it); + } + } + +/* ************************************************************************* + * Check annotations + **************************************************************************/ + + /** + * Recursively validate annotations values + */ + void validateAnnotationTree(JCTree tree) { + class AnnotationValidator extends TreeScanner { + @Override + public void visitAnnotation(JCAnnotation tree) { + if (!tree.type.isErroneous()) { + super.visitAnnotation(tree); + validateAnnotation(tree); + } + } + } + tree.accept(new AnnotationValidator()); + } + + /** + * {@literal + * Annotation types are restricted to primitives, String, an + * enum, an annotation, Class, Class, Class, arrays of the preceding. + * } + */ + void validateAnnotationType(JCTree restype) { + // restype may be null if an error occurred, so don't bother validating it + if (restype != null) { + validateAnnotationType(restype.pos(), restype.type); + } + } + + void validateAnnotationType(DiagnosticPosition pos, Type type) { + if (type.isPrimitive()) return; + if (types.isSameType(type, syms.stringType)) return; + if ((type.tsym.flags() & Flags.ENUM) != 0) return; + if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return; + if (types.cvarLowerBound(type).tsym == syms.classType.tsym) return; + if (types.isArray(type) && !types.isArray(types.elemtype(type))) { + validateAnnotationType(pos, types.elemtype(type)); + return; + } + log.error(pos, "invalid.annotation.member.type"); + } + + /** + * "It is also a compile-time error if any method declared in an + * annotation type has a signature that is override-equivalent to + * that of any public or protected method declared in class Object + * or in the interface annotation.Annotation." + * + * @jls 9.6 Annotation Types + */ + void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) { + for (Type sup = syms.annotationType; sup.hasTag(CLASS); sup = types.supertype(sup)) { + Scope s = sup.tsym.members(); + for (Scope.Entry e = s.lookup(m.name); e.scope != null; e = e.next()) { + if (e.sym.kind == MTH && + (e.sym.flags() & (PUBLIC | PROTECTED)) != 0 && + types.overrideEquivalent(m.type, e.sym.type)) + log.error(pos, "intf.annotation.member.clash", e.sym, sup); + } + } + } + + /** Check the annotations of a symbol. + */ + public void validateAnnotations(List annotations, Symbol s) { + for (JCAnnotation a : annotations) + validateAnnotation(a, s); + } + + /** Check the type annotations. + */ + public void validateTypeAnnotations(List annotations, boolean isTypeParameter) { + for (JCAnnotation a : annotations) + validateTypeAnnotation(a, isTypeParameter); + } + + /** Check an annotation of a symbol. + */ + private void validateAnnotation(JCAnnotation a, Symbol s) { + validateAnnotationTree(a); + + if (!annotationApplicable(a, s)) + log.error(a.pos(), "annotation.type.not.applicable"); + + if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) { + if (s.kind != TYP) { + log.error(a.pos(), "bad.functional.intf.anno"); + } else if (!s.isInterface() || (s.flags() & ANNOTATION) != 0) { + log.error(a.pos(), "bad.functional.intf.anno.1", diags.fragment("not.a.functional.intf", s)); + } + } + } + + public void validateTypeAnnotation(JCAnnotation a, boolean isTypeParameter) { + Assert.checkNonNull(a.type, "annotation tree hasn't been attributed yet: " + a); + validateAnnotationTree(a); + + if (a.hasTag(TYPE_ANNOTATION) && + !a.annotationType.type.isErroneous() && + !isTypeAnnotation(a, isTypeParameter)) { + log.error(a.pos(), "annotation.type.not.applicable"); + } + } + + /** + * Validate the proposed container 'repeatable' on the + * annotation type symbol 's'. Report errors at position + * 'pos'. + * + * @param s The (annotation)type declaration annotated with a @Repeatable + * @param repeatable the @Repeatable on 's' + * @param pos where to report errors + */ + public void validateRepeatable(TypeSymbol s, Attribute.Compound repeatable, DiagnosticPosition pos) { + Assert.check(types.isSameType(repeatable.type, syms.repeatableType)); + + Type t = null; + List> l = repeatable.values; + if (!l.isEmpty()) { + Assert.check(l.head.fst.name == names.value); + t = ((Attribute.Class)l.head.snd).getValue(); + } + + if (t == null) { + // errors should already have been reported during Annotate + return; + } + + validateValue(t.tsym, s, pos); + validateRetention(t.tsym, s, pos); + validateDocumented(t.tsym, s, pos); + validateInherited(t.tsym, s, pos); + validateTarget(t.tsym, s, pos); + validateDefault(t.tsym, pos); + } + + private void validateValue(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) { + Scope.Entry e = container.members().lookup(names.value); + if (e.scope != null && e.sym.kind == MTH) { + MethodSymbol m = (MethodSymbol) e.sym; + Type ret = m.getReturnType(); + if (!(ret.hasTag(ARRAY) && types.isSameType(((ArrayType)ret).elemtype, contained.type))) { + log.error(pos, "invalid.repeatable.annotation.value.return", + container, ret, types.makeArrayType(contained.type)); + } + } else { + log.error(pos, "invalid.repeatable.annotation.no.value", container); + } + } + + private void validateRetention(Symbol container, Symbol contained, DiagnosticPosition pos) { + Attribute.RetentionPolicy containerRetention = types.getRetention(container); + Attribute.RetentionPolicy containedRetention = types.getRetention(contained); + + boolean error = false; + switch (containedRetention) { + case RUNTIME: + if (containerRetention != Attribute.RetentionPolicy.RUNTIME) { + error = true; + } + break; + case CLASS: + if (containerRetention == Attribute.RetentionPolicy.SOURCE) { + error = true; + } + } + if (error ) { + log.error(pos, "invalid.repeatable.annotation.retention", + container, containerRetention, + contained, containedRetention); + } + } + + private void validateDocumented(Symbol container, Symbol contained, DiagnosticPosition pos) { + if (contained.attribute(syms.documentedType.tsym) != null) { + if (container.attribute(syms.documentedType.tsym) == null) { + log.error(pos, "invalid.repeatable.annotation.not.documented", container, contained); + } + } + } + + private void validateInherited(Symbol container, Symbol contained, DiagnosticPosition pos) { + if (contained.attribute(syms.inheritedType.tsym) != null) { + if (container.attribute(syms.inheritedType.tsym) == null) { + log.error(pos, "invalid.repeatable.annotation.not.inherited", container, contained); + } + } + } + + private void validateTarget(Symbol container, Symbol contained, DiagnosticPosition pos) { + // The set of targets the container is applicable to must be a subset + // (with respect to annotation target semantics) of the set of targets + // the contained is applicable to. The target sets may be implicit or + // explicit. + + Set containerTargets; + Attribute.Array containerTarget = getAttributeTargetAttribute(container); + if (containerTarget == null) { + containerTargets = getDefaultTargetSet(); + } else { + containerTargets = new HashSet(); + for (Attribute app : containerTarget.values) { + if (!(app instanceof Attribute.Enum)) { + continue; // recovery + } + Attribute.Enum e = (Attribute.Enum)app; + containerTargets.add(e.value.name); + } + } + + Set containedTargets; + Attribute.Array containedTarget = getAttributeTargetAttribute(contained); + if (containedTarget == null) { + containedTargets = getDefaultTargetSet(); + } else { + containedTargets = new HashSet(); + for (Attribute app : containedTarget.values) { + if (!(app instanceof Attribute.Enum)) { + continue; // recovery + } + Attribute.Enum e = (Attribute.Enum)app; + containedTargets.add(e.value.name); + } + } + + if (!isTargetSubsetOf(containerTargets, containedTargets)) { + log.error(pos, "invalid.repeatable.annotation.incompatible.target", container, contained); + } + } + + /* get a set of names for the default target */ + private Set getDefaultTargetSet() { + if (defaultTargets == null) { + Set targets = new HashSet(); + targets.add(names.ANNOTATION_TYPE); + targets.add(names.CONSTRUCTOR); + targets.add(names.FIELD); + targets.add(names.LOCAL_VARIABLE); + targets.add(names.METHOD); + targets.add(names.PACKAGE); + targets.add(names.PARAMETER); + targets.add(names.TYPE); + + defaultTargets = java.util.Collections.unmodifiableSet(targets); + } + + return defaultTargets; + } + private Set defaultTargets; + + + /** Checks that s is a subset of t, with respect to ElementType + * semantics, specifically {ANNOTATION_TYPE} is a subset of {TYPE}, + * and {TYPE_USE} covers the set {ANNOTATION_TYPE, TYPE, TYPE_USE, + * TYPE_PARAMETER}. + */ + private boolean isTargetSubsetOf(Set s, Set t) { + // Check that all elements in s are present in t + for (Name n2 : s) { + boolean currentElementOk = false; + for (Name n1 : t) { + if (n1 == n2) { + currentElementOk = true; + break; + } else if (n1 == names.TYPE && n2 == names.ANNOTATION_TYPE) { + currentElementOk = true; + break; + } else if (n1 == names.TYPE_USE && + (n2 == names.TYPE || + n2 == names.ANNOTATION_TYPE || + n2 == names.TYPE_PARAMETER)) { + currentElementOk = true; + break; + } + } + if (!currentElementOk) + return false; + } + return true; + } + + private void validateDefault(Symbol container, DiagnosticPosition pos) { + // validate that all other elements of containing type has defaults + Scope scope = container.members(); + for(Symbol elm : scope.getElements()) { + if (elm.name != names.value && + elm.kind == Kinds.MTH && + ((MethodSymbol)elm).defaultValue == null) { + log.error(pos, + "invalid.repeatable.annotation.elem.nondefault", + container, + elm); + } + } + } + + /** Is s a method symbol that overrides a method in a superclass? */ + boolean isOverrider(Symbol s) { + if (s.kind != MTH || s.isStatic()) + return false; + MethodSymbol m = (MethodSymbol)s; + TypeSymbol owner = (TypeSymbol)m.owner; + for (Type sup : types.closure(owner.type)) { + if (sup == owner.type) + continue; // skip "this" + Scope scope = sup.tsym.members(); + for (Scope.Entry e = scope.lookup(m.name); e.scope != null; e = e.next()) { + if (!e.sym.isStatic() && m.overrides(e.sym, owner, types, true)) + return true; + } + } + return false; + } + + /** Is the annotation applicable to types? */ + protected boolean isTypeAnnotation(JCAnnotation a, boolean isTypeParameter) { + Attribute.Compound atTarget = + a.annotationType.type.tsym.attribute(syms.annotationTargetType.tsym); + if (atTarget == null) { + // An annotation without @Target is not a type annotation. + return false; + } + + Attribute atValue = atTarget.member(names.value); + if (!(atValue instanceof Attribute.Array)) { + return false; // error recovery + } + + Attribute.Array arr = (Attribute.Array) atValue; + for (Attribute app : arr.values) { + if (!(app instanceof Attribute.Enum)) { + return false; // recovery + } + Attribute.Enum e = (Attribute.Enum) app; + + if (e.value.name == names.TYPE_USE) + return true; + else if (isTypeParameter && e.value.name == names.TYPE_PARAMETER) + return true; + } + return false; + } + + /** Is the annotation applicable to the symbol? */ + boolean annotationApplicable(JCAnnotation a, Symbol s) { + Attribute.Array arr = getAttributeTargetAttribute(a.annotationType.type.tsym); + Name[] targets; + + if (arr == null) { + targets = defaultTargetMetaInfo(a, s); + } else { + // TODO: can we optimize this? + targets = new Name[arr.values.length]; + for (int i=0; i members = new LinkedHashSet(); + for (Scope.Entry e = a.annotationType.type.tsym.members().elems; + e != null; + e = e.sibling) + if (e.sym.kind == MTH && e.sym.name != names.clinit && + (e.sym.flags() & SYNTHETIC) == 0) + members.add((MethodSymbol) e.sym); + + // remove the ones that are assigned values + for (JCTree arg : a.args) { + if (!arg.hasTag(ASSIGN)) continue; // recovery + JCAssign assign = (JCAssign) arg; + Symbol m = TreeInfo.symbol(assign.lhs); + if (m == null || m.type.isErroneous()) continue; + if (!members.remove(m)) { + isValid = false; + log.error(assign.lhs.pos(), "duplicate.annotation.member.value", + m.name, a.type); + } + } + + // all the remaining ones better have default values + List missingDefaults = List.nil(); + for (MethodSymbol m : members) { + if (m.defaultValue == null && !m.type.isErroneous()) { + missingDefaults = missingDefaults.append(m.name); + } + } + missingDefaults = missingDefaults.reverse(); + if (missingDefaults.nonEmpty()) { + isValid = false; + String key = (missingDefaults.size() > 1) + ? "annotation.missing.default.value.1" + : "annotation.missing.default.value"; + log.error(a.pos(), key, a.type, missingDefaults); + } + + // special case: java.lang.annotation.Target must not have + // repeated values in its value member + if (a.annotationType.type.tsym != syms.annotationTargetType.tsym || + a.args.tail == null) + return isValid; + + if (!a.args.head.hasTag(ASSIGN)) return false; // error recovery + JCAssign assign = (JCAssign) a.args.head; + Symbol m = TreeInfo.symbol(assign.lhs); + if (m.name != names.value) return false; + JCTree rhs = assign.rhs; + if (!rhs.hasTag(NEWARRAY)) return false; + JCNewArray na = (JCNewArray) rhs; + Set targets = new HashSet(); + for (JCTree elem : na.elems) { + if (!targets.add(TreeInfo.symbol(elem))) { + isValid = false; + log.error(elem.pos(), "repeated.annotation.target"); + } + } + return isValid; + } + + void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) { + if (allowAnnotations && + lint.isEnabled(LintCategory.DEP_ANN) && + (s.flags() & DEPRECATED) != 0 && + !syms.deprecatedType.isErroneous() && + s.attribute(syms.deprecatedType.tsym) == null) { + log.warning(LintCategory.DEP_ANN, + pos, "missing.deprecated.annotation"); + } + } + + void checkDeprecated(final DiagnosticPosition pos, final Symbol other, final Symbol s) { + if ((s.flags() & DEPRECATED) != 0 && + (other.flags() & DEPRECATED) == 0 && + s.outermostClass() != other.outermostClass()) { + deferredLintHandler.report(new DeferredLintHandler.LintLogger() { + @Override + public void report() { + warnDeprecated(pos, s); + } + }); + } + } + + void checkSunAPI(final DiagnosticPosition pos, final Symbol s) { + if ((s.flags() & PROPRIETARY) != 0) { + deferredLintHandler.report(new DeferredLintHandler.LintLogger() { + public void report() { + if (enableSunApiLintControl) + warnSunApi(pos, "sun.proprietary", s); + else + log.mandatoryWarning(pos, "sun.proprietary", s); + } + }); + } + } + + void checkProfile(final DiagnosticPosition pos, final Symbol s) { + if (profile != Profile.DEFAULT && (s.flags() & NOT_IN_PROFILE) != 0) { + log.error(pos, "not.in.profile", s, profile); + } + } + +/* ************************************************************************* + * Check for recursive annotation elements. + **************************************************************************/ + + /** Check for cycles in the graph of annotation elements. + */ + void checkNonCyclicElements(JCClassDecl tree) { + if ((tree.sym.flags_field & ANNOTATION) == 0) return; + Assert.check((tree.sym.flags_field & LOCKED) == 0); + try { + tree.sym.flags_field |= LOCKED; + for (JCTree def : tree.defs) { + if (!def.hasTag(METHODDEF)) continue; + JCMethodDecl meth = (JCMethodDecl)def; + checkAnnotationResType(meth.pos(), meth.restype.type); + } + } finally { + tree.sym.flags_field &= ~LOCKED; + tree.sym.flags_field |= ACYCLIC_ANN; + } + } + + void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) { + if ((tsym.flags_field & ACYCLIC_ANN) != 0) + return; + if ((tsym.flags_field & LOCKED) != 0) { + log.error(pos, "cyclic.annotation.element"); + return; + } + try { + tsym.flags_field |= LOCKED; + for (Scope.Entry e = tsym.members().elems; e != null; e = e.sibling) { + Symbol s = e.sym; + if (s.kind != Kinds.MTH) + continue; + checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType()); + } + } finally { + tsym.flags_field &= ~LOCKED; + tsym.flags_field |= ACYCLIC_ANN; + } + } + + void checkAnnotationResType(DiagnosticPosition pos, Type type) { + switch (type.getTag()) { + case CLASS: + if ((type.tsym.flags() & ANNOTATION) != 0) + checkNonCyclicElementsInternal(pos, type.tsym); + break; + case ARRAY: + checkAnnotationResType(pos, types.elemtype(type)); + break; + default: + break; // int etc + } + } + +/* ************************************************************************* + * Check for cycles in the constructor call graph. + **************************************************************************/ + + /** Check for cycles in the graph of constructors calling other + * constructors. + */ + void checkCyclicConstructors(JCClassDecl tree) { + Map callMap = new HashMap(); + + // enter each constructor this-call into the map + for (List l = tree.defs; l.nonEmpty(); l = l.tail) { + JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head); + if (app == null) continue; + JCMethodDecl meth = (JCMethodDecl) l.head; + if (TreeInfo.name(app.meth) == names._this) { + callMap.put(meth.sym, TreeInfo.symbol(app.meth)); + } else { + meth.sym.flags_field |= ACYCLIC; + } + } + + // Check for cycles in the map + Symbol[] ctors = new Symbol[0]; + ctors = callMap.keySet().toArray(ctors); + for (Symbol caller : ctors) { + checkCyclicConstructor(tree, caller, callMap); + } + } + + /** Look in the map to see if the given constructor is part of a + * call cycle. + */ + private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor, + Map callMap) { + if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) { + if ((ctor.flags_field & LOCKED) != 0) { + log.error(TreeInfo.diagnosticPositionFor(ctor, tree), + "recursive.ctor.invocation"); + } else { + ctor.flags_field |= LOCKED; + checkCyclicConstructor(tree, callMap.remove(ctor), callMap); + ctor.flags_field &= ~LOCKED; + } + ctor.flags_field |= ACYCLIC; + } + } + +/* ************************************************************************* + * Miscellaneous + **************************************************************************/ + + /** + * Return the opcode of the operator but emit an error if it is an + * error. + * @param pos position for error reporting. + * @param operator an operator + * @param tag a tree tag + * @param left type of left hand side + * @param right type of right hand side + */ + int checkOperator(DiagnosticPosition pos, + OperatorSymbol operator, + JCTree.Tag tag, + Type left, + Type right) { + if (operator.opcode == ByteCodes.error) { + log.error(pos, + "operator.cant.be.applied.1", + treeinfo.operatorName(tag), + left, right); + } + return operator.opcode; + } + + + /** + * Check for division by integer constant zero + * @param pos Position for error reporting. + * @param operator The operator for the expression + * @param operand The right hand operand for the expression + */ + void checkDivZero(DiagnosticPosition pos, Symbol operator, Type operand) { + if (operand.constValue() != null + && lint.isEnabled(LintCategory.DIVZERO) + && operand.getTag().isSubRangeOf(LONG) + && ((Number) (operand.constValue())).longValue() == 0) { + int opc = ((OperatorSymbol)operator).opcode; + if (opc == ByteCodes.idiv || opc == ByteCodes.imod + || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) { + log.warning(LintCategory.DIVZERO, pos, "div.zero"); + } + } + } + + /** + * Check for empty statements after if + */ + void checkEmptyIf(JCIf tree) { + if (tree.thenpart.hasTag(SKIP) && tree.elsepart == null && + lint.isEnabled(LintCategory.EMPTY)) + log.warning(LintCategory.EMPTY, tree.thenpart.pos(), "empty.if"); + } + + /** Check that symbol is unique in given scope. + * @param pos Position for error reporting. + * @param sym The symbol. + * @param s The scope. + */ + boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) { + if (sym.type.isErroneous()) + return true; + if (sym.owner.name == names.any) return false; + for (Scope.Entry e = s.lookup(sym.name); e.scope == s; e = e.next()) { + if (sym != e.sym && + (e.sym.flags() & CLASH) == 0 && + sym.kind == e.sym.kind && + sym.name != names.error && + (sym.kind != MTH || + types.hasSameArgs(sym.type, e.sym.type) || + types.hasSameArgs(types.erasure(sym.type), types.erasure(e.sym.type)))) { + if ((sym.flags() & VARARGS) != (e.sym.flags() & VARARGS)) { + varargsDuplicateError(pos, sym, e.sym); + return true; + } else if (sym.kind == MTH && !types.hasSameArgs(sym.type, e.sym.type, false)) { + duplicateErasureError(pos, sym, e.sym); + sym.flags_field |= CLASH; + return true; + } else { + duplicateError(pos, e.sym); + return false; + } + } + } + return true; + } + + /** Report duplicate declaration error. + */ + void duplicateErasureError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) { + if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) { + log.error(pos, "name.clash.same.erasure", sym1, sym2); + } + } + + /** Check that single-type import is not already imported or top-level defined, + * but make an exception for two single-type imports which denote the same type. + * @param pos Position for error reporting. + * @param sym The symbol. + * @param s The scope + */ + boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s) { + return checkUniqueImport(pos, sym, s, false); + } + + /** Check that static single-type import is not already imported or top-level defined, + * but make an exception for two single-type imports which denote the same type. + * @param pos Position for error reporting. + * @param sym The symbol. + * @param s The scope + */ + boolean checkUniqueStaticImport(DiagnosticPosition pos, Symbol sym, Scope s) { + return checkUniqueImport(pos, sym, s, true); + } + + /** Check that single-type import is not already imported or top-level defined, + * but make an exception for two single-type imports which denote the same type. + * @param pos Position for error reporting. + * @param sym The symbol. + * @param s The scope. + * @param staticImport Whether or not this was a static import + */ + private boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s, boolean staticImport) { + for (Scope.Entry e = s.lookup(sym.name); e.scope != null; e = e.next()) { + // is encountered class entered via a class declaration? + boolean isClassDecl = e.scope == s; + if ((isClassDecl || sym != e.sym) && + sym.kind == e.sym.kind && + sym.name != names.error && + (!staticImport || !e.isStaticallyImported())) { + if (!e.sym.type.isErroneous()) { + if (!isClassDecl) { + if (staticImport) + log.error(pos, "already.defined.static.single.import", e.sym); + else + log.error(pos, "already.defined.single.import", e.sym); + } + else if (sym != e.sym) + log.error(pos, "already.defined.this.unit", e.sym); + } + return false; + } + } + return true; + } + + /** Check that a qualified name is in canonical form (for import decls). + */ + public void checkCanonical(JCTree tree) { + if (!isCanonical(tree)) + log.error(tree.pos(), "import.requires.canonical", + TreeInfo.symbol(tree)); + } + // where + private boolean isCanonical(JCTree tree) { + while (tree.hasTag(SELECT)) { + JCFieldAccess s = (JCFieldAccess) tree; + if (s.sym.owner != TreeInfo.symbol(s.selected)) + return false; + tree = s.selected; + } + return true; + } + + /** Check that an auxiliary class is not accessed from any other file than its own. + */ + void checkForBadAuxiliaryClassAccess(DiagnosticPosition pos, Env env, ClassSymbol c) { + if (lint.isEnabled(Lint.LintCategory.AUXILIARYCLASS) && + (c.flags() & AUXILIARY) != 0 && + rs.isAccessible(env, c) && + !fileManager.isSameFile(c.sourcefile, env.toplevel.sourcefile)) + { + log.warning(pos, "auxiliary.class.accessed.from.outside.of.its.source.file", + c, c.sourcefile); + } + } + + private class ConversionWarner extends Warner { + final String uncheckedKey; + final Type found; + final Type expected; + public ConversionWarner(DiagnosticPosition pos, String uncheckedKey, Type found, Type expected) { + super(pos); + this.uncheckedKey = uncheckedKey; + this.found = found; + this.expected = expected; + } + + @Override + public void warn(LintCategory lint) { + boolean warned = this.warned; + super.warn(lint); + if (warned) return; // suppress redundant diagnostics + switch (lint) { + case UNCHECKED: + Check.this.warnUnchecked(pos(), "prob.found.req", diags.fragment(uncheckedKey), found, expected); + break; + case VARARGS: + if (method != null && + method.attribute(syms.trustMeType.tsym) != null && + isTrustMeAllowedOnMethod(method) && + !types.isReifiable(method.type.getParameterTypes().last())) { + Check.this.warnUnsafeVararg(pos(), "varargs.unsafe.use.varargs.param", method.params.last()); + } + break; + default: + throw new AssertionError("Unexpected lint: " + lint); + } + } + } + + public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) { + return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected); + } + + public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) { + return new ConversionWarner(pos, "unchecked.assign", found, expected); + } + + public void checkFunctionalInterface(JCClassDecl tree, ClassSymbol cs) { + Compound functionalType = cs.attribute(syms.functionalInterfaceType.tsym); + + if (functionalType != null) { + try { + types.findDescriptorSymbol((TypeSymbol)cs); + } catch (Types.FunctionDescriptorLookupError ex) { + DiagnosticPosition pos = tree.pos(); + for (JCAnnotation a : tree.getModifiers().annotations) { + if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) { + pos = a.pos(); + break; + } + } + log.error(pos, "bad.functional.intf.anno.1", ex.getDiagnostic()); + } + } + } +}