/******************************************************************************* * Copyright (c) 2000, 2014 IBM Corporation and others. * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/epl-v10.html * * Contributors: * IBM Corporation - initial API and implementation * Stephan Herrmann - Contributions for * bug 186342 - [compiler][null] Using annotations for null checking * bug 365519 - editorial cleanup after bug 186342 and bug 365387 * bug 388281 - [compiler][null] inheritance of null annotations as an option * bug 388795 - [compiler] detection of name clash depends on order of super interfaces * bug 388739 - [1.8][compiler] consider default methods when detecting whether a class needs to be declared abstract * bug 390883 - [1.8][compiler] Unable to override default method * bug 395002 - Self bound generic class doesn't resolve bounds properly for wildcards for certain parametrisation. * bug 401246 - [1.8][compiler] abstract class method should now trump conflicting default methods * bug 401796 - [1.8][compiler] don't treat default methods as overriding an independent inherited abstract method * bug 403867 - [1.8][compiler] Suspect error about duplicate default methods * bug 391376 - [1.8] check interaction of default methods with bridge methods and generics * bug 395681 - [compiler] Improve simulation of javac6 behavior from bug 317719 after fixing bug 388795 * bug 409473 - [compiler] JDT cannot compile against JRE 1.8 * Bug 420080 - [1.8] Overridden Default method is reported as duplicated * Bug 404690 - [1.8][compiler] revisit bridge generation after VM bug is fixed * Bug 410325 - [1.7][compiler] Generified method override different between javac and eclipse compiler * Bug 429958 - [1.8][null] evaluate new DefaultLocation attribute of @NonNullByDefault * Bug 390889 - [1.8][compiler] Evaluate options to support 1.7- projects against 1.8 JRE. *******************************************************************************/ package org.eclipse.jdt.internal.compiler.lookup; import java.util.Arrays; import org.eclipse.jdt.internal.compiler.ast.ASTNode; import org.eclipse.jdt.internal.compiler.ast.AbstractMethodDeclaration; import org.eclipse.jdt.internal.compiler.ast.Argument; import org.eclipse.jdt.internal.compiler.ast.MethodDeclaration; import org.eclipse.jdt.internal.compiler.ast.TypeParameter; import org.eclipse.jdt.internal.compiler.ast.TypeReference; import org.eclipse.jdt.internal.compiler.classfmt.ClassFileConstants; import org.eclipse.jdt.internal.compiler.impl.CompilerOptions; import org.eclipse.jdt.internal.compiler.problem.ProblemSeverities; import org.eclipse.jdt.internal.compiler.util.HashtableOfObject; import org.eclipse.jdt.internal.compiler.util.SimpleSet; import org.eclipse.jdt.internal.compiler.util.Sorting; class MethodVerifier15 extends MethodVerifier { MethodVerifier15(LookupEnvironment environment) { super(environment); } // Given `overridingMethod' which overrides `inheritedMethod' answer whether some subclass method that // differs in erasure from overridingMethod could override `inheritedMethod' protected boolean canOverridingMethodDifferInErasure(MethodBinding overridingMethod, MethodBinding inheritedMethod) { if (overridingMethod.areParameterErasuresEqual(inheritedMethod)) return false; // no further change in signature is possible due to parameterization. if (overridingMethod.declaringClass.isRawType()) return false; // no parameterization is happening anyways. return true; } boolean canSkipInheritedMethods() { if (this.type.superclass() != null) if (this.type.superclass().isAbstract() || this.type.superclass().isParameterizedType()) return false; return this.type.superInterfaces() == Binding.NO_SUPERINTERFACES; } boolean canSkipInheritedMethods(MethodBinding one, MethodBinding two) { return two == null // already know one is not null || (TypeBinding.equalsEquals(one.declaringClass, two.declaringClass) && !one.declaringClass.isParameterizedType()); } void checkConcreteInheritedMethod(MethodBinding concreteMethod, MethodBinding[] abstractMethods) { super.checkConcreteInheritedMethod(concreteMethod, abstractMethods); boolean analyseNullAnnotations = this.environment.globalOptions.isAnnotationBasedNullAnalysisEnabled; // TODO (stephan): unclear if this srcMethod is actually needed AbstractMethodDeclaration srcMethod = null; if (analyseNullAnnotations && this.type.equals(concreteMethod.declaringClass)) // is currentMethod from the current type? srcMethod = concreteMethod.sourceMethod(); boolean useTypeAnnotations = this.environment.globalOptions.sourceLevel >= ClassFileConstants.JDK1_8; boolean hasNonNullDefault = analyseNullAnnotations && concreteMethod.hasNonNullDefaultFor(Binding.DefaultLocationParameter|Binding.DefaultLocationReturnType, useTypeAnnotations); for (int i = 0, l = abstractMethods.length; i < l; i++) { MethodBinding abstractMethod = abstractMethods[i]; if (concreteMethod.isVarargs() != abstractMethod.isVarargs()) problemReporter().varargsConflict(concreteMethod, abstractMethod, this.type); // so the parameters are equal and the return type is compatible b/w the currentMethod & the substituted inheritedMethod MethodBinding originalInherited = abstractMethod.original(); if (TypeBinding.notEquals(originalInherited.returnType, concreteMethod.returnType)) if (!isAcceptableReturnTypeOverride(concreteMethod, abstractMethod)) problemReporter().unsafeReturnTypeOverride(concreteMethod, originalInherited, this.type); // check whether bridge method is already defined above for interface methods // skip generation of bridge method for current class & method if an equivalent // bridge will be/would have been generated in the context of the super class since // the bridge itself will be inherited. See https://bugs.eclipse.org/bugs/show_bug.cgi?id=298362 if (originalInherited.declaringClass.isInterface()) { if ((TypeBinding.equalsEquals(concreteMethod.declaringClass, this.type.superclass) && this.type.superclass.isParameterizedType() && !areMethodsCompatible(concreteMethod, originalInherited)) || this.type.superclass.erasure().findSuperTypeOriginatingFrom(originalInherited.declaringClass) == null) this.type.addSyntheticBridgeMethod(originalInherited, concreteMethod.original()); } if (analyseNullAnnotations && !concreteMethod.isStatic() && !abstractMethod.isStatic()) { checkNullSpecInheritance(concreteMethod, srcMethod, hasNonNullDefault, true, abstractMethod, this.type.scope, null); } } } void checkForBridgeMethod(MethodBinding currentMethod, MethodBinding inheritedMethod, MethodBinding[] allInheritedMethods) { if (currentMethod.isVarargs() != inheritedMethod.isVarargs()) problemReporter(currentMethod).varargsConflict(currentMethod, inheritedMethod, this.type); // so the parameters are equal and the return type is compatible b/w the currentMethod & the substituted inheritedMethod MethodBinding originalInherited = inheritedMethod.original(); if (TypeBinding.notEquals(originalInherited.returnType, currentMethod.returnType)) if (!isAcceptableReturnTypeOverride(currentMethod, inheritedMethod)) problemReporter(currentMethod).unsafeReturnTypeOverride(currentMethod, originalInherited, this.type); MethodBinding bridge = this.type.addSyntheticBridgeMethod(originalInherited, currentMethod.original()); if (bridge != null) { for (int i = 0, l = allInheritedMethods == null ? 0 : allInheritedMethods.length; i < l; i++) { if (allInheritedMethods[i] != null && detectInheritedNameClash(originalInherited, allInheritedMethods[i].original())) return; } // See if the new bridge clashes with any of the user methods of the class. For this check // we should check for "method descriptor clash" and not just "method signature clash". Really // what we are checking is whether there is a contention for the method dispatch table slot. // See https://bugs.eclipse.org/bugs/show_bug.cgi?id=293615. MethodBinding[] current = (MethodBinding[]) this.currentMethods.get(bridge.selector); for (int i = current.length - 1; i >= 0; --i) { final MethodBinding thisMethod = current[i]; if (thisMethod.areParameterErasuresEqual(bridge) && TypeBinding.equalsEquals(thisMethod.returnType.erasure(), bridge.returnType.erasure())) { // use inherited method for problem reporting. problemReporter(thisMethod).methodNameClash(thisMethod, inheritedMethod.declaringClass.isRawType() ? inheritedMethod : inheritedMethod.original(), ProblemSeverities.Error); return; } } } } void checkForNameClash(MethodBinding currentMethod, MethodBinding inheritedMethod) { // sent from checkMethods() to compare a current method and an inherited method that are not 'equal' // error cases: // abstract class AA<E extends Comparable> { abstract void test(E element); } // class A extends AA<Integer> { public void test(Integer i) {} } // public class B extends A { public void test(Comparable i) {} } // interface I<E extends Comparable> { void test(E element); } // class A implements I<Integer> { public void test(Integer i) {} } // public class B extends A { public void test(Comparable i) {} } // abstract class Y implements EqualityComparable<Integer>, Equivalent<String> { // public boolean equalTo(Integer other) { return true; } // } // interface Equivalent<T> { boolean equalTo(T other); } // interface EqualityComparable<T> { boolean equalTo(T other); } // class Y implements EqualityComparable, Equivalent<String>{ // public boolean equalTo(String other) { return true; } // public boolean equalTo(Object other) { return true; } // } // interface Equivalent<T> { boolean equalTo(T other); } // interface EqualityComparable { boolean equalTo(Object other); } // class A<T extends Number> { void m(T t) {} } // class B<S extends Integer> extends A<S> { void m(S t) {}} // class D extends B<Integer> { void m(Number t) {} void m(Integer t) {} } // inheritedMethods does not include I.test since A has a valid implementation // interface I<E extends Comparable<E>> { void test(E element); } // class A implements I<Integer> { public void test(Integer i) {} } // class B extends A { public void test(Comparable i) {} } if (inheritedMethod.isStatic() || currentMethod.isStatic()) { MethodBinding original = inheritedMethod.original(); // can be the same as inherited if (this.type.scope.compilerOptions().complianceLevel >= ClassFileConstants.JDK1_7 && currentMethod.areParameterErasuresEqual(original)) { problemReporter(currentMethod).methodNameClashHidden(currentMethod, inheritedMethod.declaringClass.isRawType() ? inheritedMethod : original); } return; // no chance of bridge method's clashing } if (!detectNameClash(currentMethod, inheritedMethod, false)) { // check up the hierarchy for skipped inherited methods TypeBinding[] currentParams = currentMethod.parameters; TypeBinding[] inheritedParams = inheritedMethod.parameters; int length = currentParams.length; if (length != inheritedParams.length) return; // no match for (int i = 0; i < length; i++) if (TypeBinding.notEquals(currentParams[i], inheritedParams[i])) if (currentParams[i].isBaseType() != inheritedParams[i].isBaseType() || !inheritedParams[i].isCompatibleWith(currentParams[i])) return; // no chance that another inherited method's bridge method can collide ReferenceBinding[] interfacesToVisit = null; int nextPosition = 0; ReferenceBinding superType = inheritedMethod.declaringClass; ReferenceBinding[] itsInterfaces = superType.superInterfaces(); if (itsInterfaces != Binding.NO_SUPERINTERFACES) { nextPosition = itsInterfaces.length; interfacesToVisit = itsInterfaces; } superType = superType.superclass(); // now start with its superclass while (superType != null && superType.isValidBinding()) { MethodBinding[] methods = superType.getMethods(currentMethod.selector); for (int m = 0, n = methods.length; m < n; m++) { MethodBinding substitute = computeSubstituteMethod(methods[m], currentMethod); if (substitute != null && !isSubstituteParameterSubsignature(currentMethod, substitute) && detectNameClash(currentMethod, substitute, true)) return; } if ((itsInterfaces = superType.superInterfaces()) != Binding.NO_SUPERINTERFACES) { if (interfacesToVisit == null) { interfacesToVisit = itsInterfaces; nextPosition = interfacesToVisit.length; } else { int itsLength = itsInterfaces.length; if (nextPosition + itsLength >= interfacesToVisit.length) System.arraycopy(interfacesToVisit, 0, interfacesToVisit = new ReferenceBinding[nextPosition + itsLength + 5], 0, nextPosition); nextInterface : for (int a = 0; a < itsLength; a++) { ReferenceBinding next = itsInterfaces[a]; for (int b = 0; b < nextPosition; b++) if (TypeBinding.equalsEquals(next, interfacesToVisit[b])) continue nextInterface; interfacesToVisit[nextPosition++] = next; } } } superType = superType.superclass(); } for (int i = 0; i < nextPosition; i++) { superType = interfacesToVisit[i]; if (superType.isValidBinding()) { MethodBinding[] methods = superType.getMethods(currentMethod.selector); for (int m = 0, n = methods.length; m < n; m++){ MethodBinding substitute = computeSubstituteMethod(methods[m], currentMethod); if (substitute != null && !isSubstituteParameterSubsignature(currentMethod, substitute) && detectNameClash(currentMethod, substitute, true)) return; } if ((itsInterfaces = superType.superInterfaces()) != Binding.NO_SUPERINTERFACES) { int itsLength = itsInterfaces.length; if (nextPosition + itsLength >= interfacesToVisit.length) System.arraycopy(interfacesToVisit, 0, interfacesToVisit = new ReferenceBinding[nextPosition + itsLength + 5], 0, nextPosition); nextInterface : for (int a = 0; a < itsLength; a++) { ReferenceBinding next = itsInterfaces[a]; for (int b = 0; b < nextPosition; b++) if (TypeBinding.equalsEquals(next, interfacesToVisit[b])) continue nextInterface; interfacesToVisit[nextPosition++] = next; } } } } } } void checkInheritedMethods(MethodBinding inheritedMethod, MethodBinding otherInheritedMethod) { // the 2 inherited methods clash because of a parameterized type overrides a raw type // interface I { void foo(A a); } // class Y { void foo(A<String> a) {} } // abstract class X extends Y implements I { } // class A<T> {} // in this case the 2 inherited methods clash because of type variables // interface I { <T, S> void foo(T t); } // class Y { <T> void foo(T t) {} } // abstract class X extends Y implements I {} if (inheritedMethod.isStatic()) return; if (this.environment.globalOptions.complianceLevel < ClassFileConstants.JDK1_7 && inheritedMethod.declaringClass.isInterface()) return; // JDK7 checks for name clashes in interface inheritance, while JDK6 and below don't. See https://bugs.eclipse.org/bugs/show_bug.cgi?id=354229 detectInheritedNameClash(inheritedMethod.original(), otherInheritedMethod.original()); } // 8.4.8.4 void checkInheritedMethods(MethodBinding[] methods, int length, boolean[] isOverridden, boolean[] isInherited) { boolean continueInvestigation = true; MethodBinding concreteMethod = null; MethodBinding abstractSuperClassMethod = null; boolean playingTrump = false; // invariant: playingTrump => (concreteMethod == null) for (int i = 0; i < length; i++) { if (!methods[i].declaringClass.isInterface() && TypeBinding.notEquals(methods[i].declaringClass, this.type) && methods[i].isAbstract()) { abstractSuperClassMethod = methods[i]; break; } } for (int i = 0; i < length; i++) { // methods not inherited as of 8.4.8 cannot create a name clash, // but could still cause errors against return types etc. (below) if (isInherited[i] && !methods[i].isAbstract()) { // 8.4.8.4 defines an exception for default methods if // (a) there exists an abstract method declared in a superclass of C and inherited by C // (b) that is override-equivalent with the two methods. if (methods[i].isDefaultMethod() && abstractSuperClassMethod != null // condition (a) && areParametersEqual(abstractSuperClassMethod, methods[i]) // condition (b)... && concreteMethod == null) { // skip, class method trumps this default method (concreteMethod remains null) playingTrump = true; } else { playingTrump = false; if (concreteMethod != null) { // re-checking compatibility is needed for https://bugs.eclipse.org/346029 if (isOverridden[i] && areMethodsCompatible(concreteMethod, methods[i])) { continue; } // https://bugs.eclipse.org/195802 with https://bugs.eclipse.org/410325 // If a replace method (from findReplacedMethod()) is the rawified version of another // don't count this as duplicates: // (Not asking ParameterizedGenericMethodBinding.isRawMethod(), // because that is true only for methods of a RawTypeBinding, // but here we look for rawness regarding the method's type variables). if (TypeBinding.equalsEquals(concreteMethod.declaringClass, methods[i].declaringClass) && concreteMethod.typeVariables.length != methods[i].typeVariables.length) { if (concreteMethod.typeVariables == Binding.NO_TYPE_VARIABLES && concreteMethod.original() == methods[i]) continue; if (methods[i].typeVariables == Binding.NO_TYPE_VARIABLES && methods[i].original() == concreteMethod) continue; } problemReporter().duplicateInheritedMethods(this.type, concreteMethod, methods[i], this.environment.globalOptions.sourceLevel >= ClassFileConstants.JDK1_8); continueInvestigation = false; } concreteMethod = methods[i]; } } } if (continueInvestigation) { if (playingTrump) { // multiple abstract & default methods are OK on this branch, but then the class must be declared abstract: if (!this.type.isAbstract()) { problemReporter().abstractMethodMustBeImplemented(this.type, abstractSuperClassMethod); return; } } else { if (concreteMethod != null && concreteMethod.isDefaultMethod()) { if (this.environment.globalOptions.complianceLevel >= ClassFileConstants.JDK1_8) { if (!checkInheritedDefaultMethods(methods, length)) return; } } } super.checkInheritedMethods(methods, length, isOverridden, isInherited); } } boolean checkInheritedDefaultMethods(MethodBinding[] methods, int length) { // JLS8 9.4.1 (interface) and 8.4.8.4 (class): // default method clashes with other inherited method which is override-equivalent if (length < 2) return true; boolean ok = true; findDefaultMethod: for (int i=0; i<length; i++) { if (methods[i].isDefaultMethod()) { findEquivalent: for (int j=0; j<length; j++) { if (j == i) continue findEquivalent; if (isMethodSubsignature(methods[i], methods[j])) { if (!doesMethodOverride(methods[i], methods[j]) && !doesMethodOverride(methods[j], methods[i])) { problemReporter().inheritedDefaultMethodConflictsWithOtherInherited(this.type, methods[i], methods[j]); ok = false; } continue findDefaultMethod; } } } } return ok; } boolean checkInheritedReturnTypes(MethodBinding method, MethodBinding otherMethod) { if (areReturnTypesCompatible(method, otherMethod)) return true; /* We used to have some checks here to see if we would have already blamed the super type and if so avoid blaming the current type again. I have gotten rid of them as they in fact short circuit error reporting in cases where they should not. This means that occasionally we would report the error twice - the diagnostics is valid however, albeit arguably redundant. See https://bugs.eclipse.org/bugs/show_bug.cgi?id=334313. For an example of a test where we do this extra reporting see org.eclipse.jdt.core.tests.compiler.regression.MethodVerifyTest.test159() */ // check to see if this is just a warning, if so report it & skip to next method if (isUnsafeReturnTypeOverride(method, otherMethod)) { if (!method.declaringClass.implementsInterface(otherMethod.declaringClass, false)) problemReporter(method).unsafeReturnTypeOverride(method, otherMethod, this.type); return true; } return false; } void checkAgainstInheritedMethods(MethodBinding currentMethod, MethodBinding[] methods, int length, MethodBinding[] allInheritedMethods) { super.checkAgainstInheritedMethods(currentMethod, methods, length, allInheritedMethods); CompilerOptions options = this.environment.globalOptions; if (options.isAnnotationBasedNullAnalysisEnabled && (currentMethod.tagBits & TagBits.IsNullnessKnown) == 0) { // if annotations are inherited these have been checked during STB.resolveTypesFor() (for methods explicit in this.type) AbstractMethodDeclaration srcMethod = null; if (this.type.equals(currentMethod.declaringClass)) // is currentMethod from the current type? srcMethod = currentMethod.sourceMethod(); boolean useTypeAnnotations = options.sourceLevel >= ClassFileConstants.JDK1_8; boolean hasNonNullDefault = currentMethod.hasNonNullDefaultFor(Binding.DefaultLocationParameter|Binding.DefaultLocationReturnType, useTypeAnnotations); for (int i = length; --i >= 0;) if (!currentMethod.isStatic() && !methods[i].isStatic()) checkNullSpecInheritance(currentMethod, srcMethod, hasNonNullDefault, true, methods[i], this.type.scope, null); } } void checkNullSpecInheritance(MethodBinding currentMethod, AbstractMethodDeclaration srcMethod, boolean hasNonNullDefault, boolean complain, MethodBinding inheritedMethod, Scope scope, InheritedNonNullnessInfo[] inheritedNonNullnessInfos) { complain &= !currentMethod.isConstructor(); if (!hasNonNullDefault && !complain && !this.environment.globalOptions.inheritNullAnnotations) { // nothing to be done, take the shortcut currentMethod.tagBits |= TagBits.IsNullnessKnown; return; } // in this context currentMethod can be inherited, too. Recurse if needed. if (TypeBinding.notEquals(currentMethod.declaringClass, this.type) && (currentMethod.tagBits & TagBits.IsNullnessKnown) == 0) { this.buddyImplicitNullAnnotationsVerifier.checkImplicitNullAnnotations(currentMethod, srcMethod, complain, scope); } super.checkNullSpecInheritance(currentMethod, srcMethod, hasNonNullDefault, complain, inheritedMethod, scope, inheritedNonNullnessInfos); } void reportRawReferences() { CompilerOptions compilerOptions = this.type.scope.compilerOptions(); if (compilerOptions.sourceLevel < ClassFileConstants.JDK1_5 // shouldn't whine at all || compilerOptions.reportUnavoidableGenericTypeProblems) { // must have already whined return; } /* Code below is only for a method that does not override/implement a super type method. If it were to, it would have been handled in checkAgainstInheritedMethods. */ Object [] methodArray = this.currentMethods.valueTable; for (int s = methodArray.length; --s >= 0;) { if (methodArray[s] == null) continue; MethodBinding[] current = (MethodBinding[]) methodArray[s]; for (int i = 0, length = current.length; i < length; i++) { MethodBinding currentMethod = current[i]; if ((currentMethod.modifiers & (ExtraCompilerModifiers.AccImplementing | ExtraCompilerModifiers.AccOverriding)) == 0) { AbstractMethodDeclaration methodDecl = currentMethod.sourceMethod(); if (methodDecl == null) return; TypeBinding [] parameterTypes = currentMethod.parameters; Argument[] arguments = methodDecl.arguments; for (int j = 0, size = currentMethod.parameters.length; j < size; j++) { TypeBinding parameterType = parameterTypes[j]; Argument arg = arguments[j]; if (parameterType.leafComponentType().isRawType() && compilerOptions.getSeverity(CompilerOptions.RawTypeReference) != ProblemSeverities.Ignore && (arg.type.bits & ASTNode.IgnoreRawTypeCheck) == 0) { methodDecl.scope.problemReporter().rawTypeReference(arg.type, parameterType); } } if (!methodDecl.isConstructor() && methodDecl instanceof MethodDeclaration) { TypeReference returnType = ((MethodDeclaration) methodDecl).returnType; TypeBinding methodType = currentMethod.returnType; if (returnType != null) { if (methodType.leafComponentType().isRawType() && compilerOptions.getSeverity(CompilerOptions.RawTypeReference) != ProblemSeverities.Ignore && (returnType.bits & ASTNode.IgnoreRawTypeCheck) == 0) { methodDecl.scope.problemReporter().rawTypeReference(returnType, methodType); } } } } } } } public void reportRawReferences(MethodBinding currentMethod, MethodBinding inheritedMethod) { CompilerOptions compilerOptions = this.type.scope.compilerOptions(); if (compilerOptions.sourceLevel < ClassFileConstants.JDK1_5 // shouldn't whine at all || compilerOptions.reportUnavoidableGenericTypeProblems) { // must have already whined return; } AbstractMethodDeclaration methodDecl = currentMethod.sourceMethod(); if (methodDecl == null) return; TypeBinding [] parameterTypes = currentMethod.parameters; TypeBinding [] inheritedParameterTypes = inheritedMethod.parameters; Argument[] arguments = methodDecl.arguments; for (int j = 0, size = currentMethod.parameters.length; j < size; j++) { TypeBinding parameterType = parameterTypes[j]; TypeBinding inheritedParameterType = inheritedParameterTypes[j]; Argument arg = arguments[j]; if (parameterType.leafComponentType().isRawType()) { if (inheritedParameterType.leafComponentType().isRawType()) { arg.binding.tagBits |= TagBits.ForcedToBeRawType; } else { if (compilerOptions.getSeverity(CompilerOptions.RawTypeReference) != ProblemSeverities.Ignore && (arg.type.bits & ASTNode.IgnoreRawTypeCheck) == 0) { methodDecl.scope.problemReporter().rawTypeReference(arg.type, parameterType); } } } } TypeReference returnType = null; if (!methodDecl.isConstructor() && methodDecl instanceof MethodDeclaration && (returnType = ((MethodDeclaration) methodDecl).returnType) != null) { final TypeBinding inheritedMethodType = inheritedMethod.returnType; final TypeBinding methodType = currentMethod.returnType; if (methodType.leafComponentType().isRawType()) { if (inheritedMethodType.leafComponentType().isRawType()) { // } else { if ((returnType.bits & ASTNode.IgnoreRawTypeCheck) == 0 && compilerOptions.getSeverity(CompilerOptions.RawTypeReference) != ProblemSeverities.Ignore) { methodDecl.scope.problemReporter().rawTypeReference(returnType, methodType); } } } } } void checkMethods() { boolean mustImplementAbstractMethods = mustImplementAbstractMethods(); boolean skipInheritedMethods = mustImplementAbstractMethods && canSkipInheritedMethods(); // have a single concrete superclass so only check overridden methods boolean isOrEnclosedByPrivateType = this.type.isOrEnclosedByPrivateType(); char[][] methodSelectors = this.inheritedMethods.keyTable; nextSelector : for (int s = methodSelectors.length; --s >= 0;) { if (methodSelectors[s] == null) continue nextSelector; MethodBinding[] current = (MethodBinding[]) this.currentMethods.get(methodSelectors[s]); MethodBinding[] inherited = (MethodBinding[]) this.inheritedMethods.valueTable[s]; // ensure that if we have a concrete method this shows up at position [0]: inherited = Sorting.concreteFirst(inherited, inherited.length); // https://bugs.eclipse.org/bugs/show_bug.cgi?id=296660, if current type is exposed, // inherited methods of super classes are too. current != null case handled below. if (current == null && !isOrEnclosedByPrivateType) { int length = inherited.length; for (int i = 0; i < length; i++){ inherited[i].original().modifiers |= ExtraCompilerModifiers.AccLocallyUsed; } } if (current == null && this.type.isPublic()) { int length = inherited.length; for (int i = 0; i < length; i++) { MethodBinding inheritedMethod = inherited[i]; if (inheritedMethod.isPublic() && (!inheritedMethod.declaringClass.isInterface() && !inheritedMethod.declaringClass.isPublic())) this.type.addSyntheticBridgeMethod(inheritedMethod.original()); } } if (current == null && skipInheritedMethods) continue nextSelector; if (inherited.length == 1 && current == null) { // handle the common case if (mustImplementAbstractMethods && inherited[0].isAbstract()) checkAbstractMethod(inherited[0]); continue nextSelector; } int index = -1; int inheritedLength = inherited.length; MethodBinding[] matchingInherited = new MethodBinding[inheritedLength]; MethodBinding[] foundMatch = new MethodBinding[inheritedLength]; // null is no match, otherwise value is matching currentMethod // skip tracks inherited methods which can be safely ignored for one of these reasons: // - methods that have matched other inherited methods // either because they match the same currentMethod or match each other // - methods that are overridden by a current method boolean[] skip = new boolean[inheritedLength]; boolean[] isOverridden = new boolean[inheritedLength]; boolean[] isInherited = new boolean[inheritedLength]; Arrays.fill(isInherited, true); if (current != null) { for (int i = 0, length1 = current.length; i < length1; i++) { MethodBinding currentMethod = current[i]; MethodBinding[] nonMatchingInherited = null; for (int j = 0; j < inheritedLength; j++) { MethodBinding inheritedMethod = computeSubstituteMethod(inherited[j], currentMethod); if (inheritedMethod != null) { if (foundMatch[j] == null && isSubstituteParameterSubsignature(currentMethod, inheritedMethod)) { // already checked compatibility, do visibility etc. also indicate overriding? If so ignore inheritedMethod further downstream isOverridden[j] = skip[j] = couldMethodOverride(currentMethod, inheritedMethod); matchingInherited[++index] = inheritedMethod; foundMatch[j] = currentMethod; } else { // best place to check each currentMethod against each non-matching inheritedMethod checkForNameClash(currentMethod, inheritedMethod); if (inheritedLength > 1) { if (nonMatchingInherited == null) nonMatchingInherited = new MethodBinding[inheritedLength]; nonMatchingInherited[j] = inheritedMethod; } } } } if (index >= 0) { // see addtional comments in https://bugs.eclipse.org/bugs/show_bug.cgi?id=122881 // if (index > 0 && currentMethod.declaringClass.isInterface()) // only check when inherited methods are from interfaces // checkInheritedReturnTypes(matchingInherited, index + 1); checkAgainstInheritedMethods(currentMethod, matchingInherited, index + 1, nonMatchingInherited); // pass in the length of matching while (index >= 0) matchingInherited[index--] = null; // clear the contents of the matching methods } } } // first round: collect information into skip and isOverridden by comparing all pairs: // (and perform some side effects : bridge methods & use flags) for (int i = 0; i < inheritedLength; i++) { MethodBinding matchMethod = foundMatch[i]; if (matchMethod == null && current != null && this.type.isPublic()) { // current == null case handled already. MethodBinding inheritedMethod = inherited[i]; if (inheritedMethod.isPublic() && (!inheritedMethod.declaringClass.isInterface() && !inheritedMethod.declaringClass.isPublic())) { this.type.addSyntheticBridgeMethod(inheritedMethod.original()); } } // https://bugs.eclipse.org/bugs/show_bug.cgi?id=296660, if current type is exposed, // inherited methods of super classes are too. current == null case handled already. if (!isOrEnclosedByPrivateType && matchMethod == null && current != null) { inherited[i].original().modifiers |= ExtraCompilerModifiers.AccLocallyUsed; } MethodBinding inheritedMethod = inherited[i]; for (int j = i + 1; j < inheritedLength; j++) { MethodBinding otherInheritedMethod = inherited[j]; if (matchMethod == foundMatch[j] && matchMethod != null) continue; // both inherited methods matched the same currentMethod if (canSkipInheritedMethods(inheritedMethod, otherInheritedMethod)) continue; // Skip the otherInheritedMethod if it is completely replaced by inheritedMethod // This elimination used to happen rather eagerly in computeInheritedMethods step // itself earlier. (https://bugs.eclipse.org/bugs/show_bug.cgi?id=302358) if (TypeBinding.notEquals(inheritedMethod.declaringClass, otherInheritedMethod.declaringClass)) { // these method calls produce their effect as side-effects into skip and isOverridden: if (isSkippableOrOverridden(inheritedMethod, otherInheritedMethod, skip, isOverridden, isInherited, j)) continue; if (isSkippableOrOverridden(otherInheritedMethod, inheritedMethod, skip, isOverridden, isInherited, i)) continue; } } } // second round: collect and check matchingInherited, directly check methods with no replacing etc. for (int i = 0; i < inheritedLength; i++) { MethodBinding matchMethod = foundMatch[i]; if (skip[i]) continue; MethodBinding inheritedMethod = inherited[i]; if (matchMethod == null) matchingInherited[++index] = inheritedMethod; for (int j = i + 1; j < inheritedLength; j++) { if (foundMatch[j] == null) { MethodBinding otherInheritedMethod = inherited[j]; if (matchMethod == foundMatch[j] && matchMethod != null) continue; // both inherited methods matched the same currentMethod if (canSkipInheritedMethods(inheritedMethod, otherInheritedMethod)) continue; MethodBinding replaceMatch; if ((replaceMatch = findReplacedMethod(inheritedMethod, otherInheritedMethod)) != null) { matchingInherited[++index] = replaceMatch; skip[j] = true; } else if ((replaceMatch = findReplacedMethod(otherInheritedMethod, inheritedMethod)) != null) { matchingInherited[++index] = replaceMatch; skip[j] = true; } else if (matchMethod == null) { // none replaced by the other, check these methods against each other now: checkInheritedMethods(inheritedMethod, otherInheritedMethod); } } } if (index == -1) continue; if (index > 0) { int length = index + 1; boolean[] matchingIsOverridden; boolean[] matchingIsInherited; if (length != inheritedLength) { // transfer inherited & overridden status to align with subset of methods. matchingIsOverridden = new boolean[length]; matchingIsInherited = new boolean[length]; for (int j = 0; j < length; j++) { for (int k = 0; k < inheritedLength; k++) { if (matchingInherited[j] == inherited[k]) { matchingIsOverridden[j] = isOverridden[k]; matchingIsInherited[j] = isInherited[k]; break; } } } } else { matchingIsOverridden = isOverridden; matchingIsInherited = isInherited; } checkInheritedMethods(matchingInherited, length, matchingIsOverridden, matchingIsInherited); // pass in the length of matching } else if (mustImplementAbstractMethods && matchingInherited[0].isAbstract() && matchMethod == null) checkAbstractMethod(matchingInherited[0]); while (index >= 0) matchingInherited[index--] = null; // clear the previous contents of the matching methods } } } /* mark as skippable * - any interface method implemented by a class method * - an x method (x in {class, interface}), for which another x method with a subsignature was found * mark as isOverridden * - any skippable method as defined above iff it is actually overridden by the specific method (disregarding visibility etc.) * Note, that 'idx' corresponds to the position of 'general' in the arrays 'skip' and 'isOverridden' * TODO(stephan) currently (as of Bug 410325), the boarder between skip and isOverridden is blurred, * should reassess after more experience with this patch. */ boolean isSkippableOrOverridden(MethodBinding specific, MethodBinding general, boolean[] skip, boolean[] isOverridden, boolean[] isInherited, int idx) { boolean specificIsInterface = specific.declaringClass.isInterface(); boolean generalIsInterface = general.declaringClass.isInterface(); if (!specificIsInterface && generalIsInterface) { if (!specific.isAbstract() && isParameterSubsignature(specific, general)) { // 8.4.8: abstract and default methods are not inherited if a concrete method with a subsignature is defined or inherited in C isInherited[idx] = false; return true; } else if (isInterfaceMethodImplemented(general, specific, general.declaringClass)) { skip[idx] = true; isOverridden[idx] = true; return true; } } else if (specificIsInterface == generalIsInterface) { if (specific.declaringClass.isCompatibleWith(general.declaringClass) && isMethodSubsignature(specific, general)) { skip[idx] = true; isOverridden[idx] = true; return true; } } return false; } /* 'general' is considered as replaced by 'specific' if * - 'specific' is "at least as concrete as" 'general' * - 'specific' has a signature that is a subsignature of the substituted signature of 'general' (as seen from specific's declaring class) * - default methods should also be considered replaced by class methods that meet the signature that is a subsignature criteria. */ MethodBinding findReplacedMethod(MethodBinding specific, MethodBinding general) { MethodBinding generalSubstitute = computeSubstituteMethod(general, specific); if (generalSubstitute != null && (!specific.isAbstract() || general.isAbstract() || (general.isDefaultMethod() && specific.declaringClass.isClass())) // if (abstract(specific) => abstract(general)) check if 'specific' overrides 'general' && isSubstituteParameterSubsignature(specific, generalSubstitute)) { return generalSubstitute; } return null; } void checkTypeVariableMethods(TypeParameter typeParameter) { char[][] methodSelectors = this.inheritedMethods.keyTable; nextSelector : for (int s = methodSelectors.length; --s >= 0;) { if (methodSelectors[s] == null) continue nextSelector; MethodBinding[] inherited = (MethodBinding[]) this.inheritedMethods.valueTable[s]; if (inherited.length == 1) continue nextSelector; int index = -1; MethodBinding[] matchingInherited = new MethodBinding[inherited.length]; for (int i = 0, length = inherited.length; i < length; i++) { while (index >= 0) matchingInherited[index--] = null; // clear the previous contents of the matching methods MethodBinding inheritedMethod = inherited[i]; if (inheritedMethod != null) { matchingInherited[++index] = inheritedMethod; for (int j = i + 1; j < length; j++) { MethodBinding otherInheritedMethod = inherited[j]; if (canSkipInheritedMethods(inheritedMethod, otherInheritedMethod)) continue; otherInheritedMethod = computeSubstituteMethod(otherInheritedMethod, inheritedMethod); if (otherInheritedMethod != null && isSubstituteParameterSubsignature(inheritedMethod, otherInheritedMethod)) { matchingInherited[++index] = otherInheritedMethod; inherited[j] = null; // do not want to find it again } } } if (index > 0) { MethodBinding first = matchingInherited[0]; int count = index + 1; while (--count > 0) { MethodBinding match = matchingInherited[count]; // https://bugs.eclipse.org/bugs/show_bug.cgi?id=314556 MethodBinding interfaceMethod = null, implementation = null; if (first.declaringClass.isInterface()) { interfaceMethod = first; } else if (first.declaringClass.isClass()) { implementation = first; } if (match.declaringClass.isInterface()) { interfaceMethod = match; } else if (match.declaringClass.isClass()) { implementation = match; } if (interfaceMethod != null && implementation != null && !isAsVisible(implementation, interfaceMethod)) problemReporter().inheritedMethodReducesVisibility(typeParameter, implementation, new MethodBinding [] {interfaceMethod}); if (areReturnTypesCompatible(first, match)) continue; // unrelated interfaces - check to see if return types are compatible if (first.declaringClass.isInterface() && match.declaringClass.isInterface() && areReturnTypesCompatible(match, first)) continue; break; } if (count > 0) { // All inherited methods do NOT have the same vmSignature problemReporter().inheritedMethodsHaveIncompatibleReturnTypes(typeParameter, matchingInherited, index + 1); continue nextSelector; } } } } } boolean detectInheritedNameClash(MethodBinding inherited, MethodBinding otherInherited) { if (!inherited.areParameterErasuresEqual(otherInherited)) return false; // https://bugs.eclipse.org/bugs/show_bug.cgi?id=322001 // https://bugs.eclipse.org/bugs/show_bug.cgi?id=323693 // When reporting a name clash between two inherited methods, we should not look for a // signature clash, but instead should be looking for method descriptor clash. if (TypeBinding.notEquals(inherited.returnType.erasure(), otherInherited.returnType.erasure())) return false; // skip it if otherInherited is defined by a subtype of inherited's declaringClass or vice versa. // avoid being order sensitive and check with the roles reversed also. if (TypeBinding.notEquals(inherited.declaringClass.erasure(), otherInherited.declaringClass.erasure())) { if (inherited.declaringClass.findSuperTypeOriginatingFrom(otherInherited.declaringClass) != null) return false; if (otherInherited.declaringClass.findSuperTypeOriginatingFrom(inherited.declaringClass) != null) return false; } problemReporter().inheritedMethodsHaveNameClash(this.type, inherited, otherInherited); return true; } boolean detectNameClash(MethodBinding current, MethodBinding inherited, boolean treatAsSynthetic) { MethodBinding methodToCheck = inherited; MethodBinding original = methodToCheck.original(); // can be the same as inherited if (!current.areParameterErasuresEqual(original)) return false; int severity = ProblemSeverities.Error; if (this.environment.globalOptions.complianceLevel == ClassFileConstants.JDK1_6) { // for 1.6 return types also need to be checked // https://bugs.eclipse.org/bugs/show_bug.cgi?id=317719 if (TypeBinding.notEquals(current.returnType.erasure(), original.returnType.erasure())) severity = ProblemSeverities.Warning; } if (!treatAsSynthetic) { // For a user method, see if current class overrides the inherited method. If it does, // then any grievance we may have ought to be against the current class's method and // NOT against any super implementations. https://bugs.eclipse.org/bugs/show_bug.cgi?id=293615 // https://bugs.eclipse.org/bugs/show_bug.cgi?id=315978 : we now defer this rather expensive // check to just before reporting (the incorrect) name clash. In the event there is no name // clash to report to begin with (the common case), no penalty needs to be paid. MethodBinding[] currentNamesakes = (MethodBinding[]) this.currentMethods.get(inherited.selector); if (currentNamesakes.length > 1) { // we know it ought to at least one and that current is NOT the override for (int i = 0, length = currentNamesakes.length; i < length; i++) { MethodBinding currentMethod = currentNamesakes[i]; if (currentMethod != current && doesMethodOverride(currentMethod, inherited)) { methodToCheck = currentMethod; break; } } } } original = methodToCheck.original(); // can be the same as inherited if (!current.areParameterErasuresEqual(original)) return false; original = inherited.original(); // For error reporting use, inherited.original() problemReporter(current).methodNameClash(current, inherited.declaringClass.isRawType() ? inherited : original, severity); if (severity == ProblemSeverities.Warning) return false; return true; } boolean doTypeVariablesClash(MethodBinding one, MethodBinding substituteTwo) { // one has type variables and substituteTwo did not pass bounds check in computeSubstituteMethod() return one.typeVariables != Binding.NO_TYPE_VARIABLES && !(substituteTwo instanceof ParameterizedGenericMethodBinding); } SimpleSet findSuperinterfaceCollisions(ReferenceBinding superclass, ReferenceBinding[] superInterfaces) { ReferenceBinding[] interfacesToVisit = null; int nextPosition = 0; ReferenceBinding[] itsInterfaces = superInterfaces; if (itsInterfaces != Binding.NO_SUPERINTERFACES) { nextPosition = itsInterfaces.length; interfacesToVisit = itsInterfaces; } boolean isInconsistent = this.type.isHierarchyInconsistent(); ReferenceBinding superType = superclass; while (superType != null && superType.isValidBinding()) { isInconsistent |= superType.isHierarchyInconsistent(); if ((itsInterfaces = superType.superInterfaces()) != Binding.NO_SUPERINTERFACES) { if (interfacesToVisit == null) { interfacesToVisit = itsInterfaces; nextPosition = interfacesToVisit.length; } else { int itsLength = itsInterfaces.length; if (nextPosition + itsLength >= interfacesToVisit.length) System.arraycopy(interfacesToVisit, 0, interfacesToVisit = new ReferenceBinding[nextPosition + itsLength + 5], 0, nextPosition); nextInterface : for (int a = 0; a < itsLength; a++) { ReferenceBinding next = itsInterfaces[a]; for (int b = 0; b < nextPosition; b++) if (TypeBinding.equalsEquals(next, interfacesToVisit[b])) continue nextInterface; interfacesToVisit[nextPosition++] = next; } } } superType = superType.superclass(); } for (int i = 0; i < nextPosition; i++) { superType = interfacesToVisit[i]; if (superType.isValidBinding()) { isInconsistent |= superType.isHierarchyInconsistent(); if ((itsInterfaces = superType.superInterfaces()) != Binding.NO_SUPERINTERFACES) { int itsLength = itsInterfaces.length; if (nextPosition + itsLength >= interfacesToVisit.length) System.arraycopy(interfacesToVisit, 0, interfacesToVisit = new ReferenceBinding[nextPosition + itsLength + 5], 0, nextPosition); nextInterface : for (int a = 0; a < itsLength; a++) { ReferenceBinding next = itsInterfaces[a]; for (int b = 0; b < nextPosition; b++) if (TypeBinding.equalsEquals(next, interfacesToVisit[b])) continue nextInterface; interfacesToVisit[nextPosition++] = next; } } } } if (!isInconsistent) return null; // hierarchy is consistent so no collisions are possible SimpleSet copy = null; for (int i = 0; i < nextPosition; i++) { ReferenceBinding current = interfacesToVisit[i]; if (current.isValidBinding()) { TypeBinding erasure = current.erasure(); for (int j = i + 1; j < nextPosition; j++) { ReferenceBinding next = interfacesToVisit[j]; if (next.isValidBinding() && TypeBinding.equalsEquals(next.erasure(), erasure)) { if (copy == null) copy = new SimpleSet(nextPosition); copy.add(interfacesToVisit[i]); copy.add(interfacesToVisit[j]); } } } } return copy; } boolean isAcceptableReturnTypeOverride(MethodBinding currentMethod, MethodBinding inheritedMethod) { // called when currentMethod's return type is compatible with inheritedMethod's return type if (inheritedMethod.declaringClass.isRawType()) return true; // since the inheritedMethod comes from a raw type, the return type is always acceptable MethodBinding originalInherited = inheritedMethod.original(); TypeBinding originalInheritedReturnType = originalInherited.returnType.leafComponentType(); if (originalInheritedReturnType.isParameterizedTypeWithActualArguments()) return !currentMethod.returnType.leafComponentType().isRawType(); // raw types issue a warning if inherited is parameterized TypeBinding currentReturnType = currentMethod.returnType.leafComponentType(); switch (currentReturnType.kind()) { case Binding.TYPE_PARAMETER : if (TypeBinding.equalsEquals(currentReturnType, inheritedMethod.returnType.leafComponentType())) return true; //$FALL-THROUGH$ default : if (originalInheritedReturnType.isTypeVariable()) if (((TypeVariableBinding) originalInheritedReturnType).declaringElement == originalInherited) return false; return true; } } // caveat: returns false if a method is implemented that needs a bridge method boolean isInterfaceMethodImplemented(MethodBinding inheritedMethod, MethodBinding existingMethod, ReferenceBinding superType) { if (inheritedMethod.original() != inheritedMethod && existingMethod.declaringClass.isInterface()) return false; // must hold onto ParameterizedMethod to see if a bridge method is necessary inheritedMethod = computeSubstituteMethod(inheritedMethod, existingMethod); return inheritedMethod != null && (TypeBinding.equalsEquals(inheritedMethod.returnType, existingMethod.returnType) // need to keep around to produce bridge methods? ... || (TypeBinding.notEquals(this.type, existingMethod.declaringClass) // ... not if inheriting the bridge situation from a superclass && !existingMethod.declaringClass.isInterface())) && doesMethodOverride(existingMethod, inheritedMethod); } public boolean isMethodSubsignature(MethodBinding method, MethodBinding inheritedMethod) { if (!org.eclipse.jdt.core.compiler.CharOperation.equals(method.selector, inheritedMethod.selector)) return false; // need to switch back to the original if the method is from a ParameterizedType if (method.declaringClass.isParameterizedType()) method = method.original(); MethodBinding inheritedOriginal = method.findOriginalInheritedMethod(inheritedMethod); return isParameterSubsignature(method, inheritedOriginal == null ? inheritedMethod : inheritedOriginal); } boolean isUnsafeReturnTypeOverride(MethodBinding currentMethod, MethodBinding inheritedMethod) { // called when currentMethod's return type is NOT compatible with inheritedMethod's return type // JLS 3 �8.4.5: more are accepted, with an unchecked conversion if (TypeBinding.equalsEquals(currentMethod.returnType, inheritedMethod.returnType.erasure())) { TypeBinding[] currentParams = currentMethod.parameters; TypeBinding[] inheritedParams = inheritedMethod.parameters; for (int i = 0, l = currentParams.length; i < l; i++) if (!areTypesEqual(currentParams[i], inheritedParams[i])) return true; } if (currentMethod.typeVariables == Binding.NO_TYPE_VARIABLES && inheritedMethod.original().typeVariables != Binding.NO_TYPE_VARIABLES && currentMethod.returnType.erasure().findSuperTypeOriginatingFrom(inheritedMethod.returnType.erasure()) != null) { return true; } return false; } boolean reportIncompatibleReturnTypeError(MethodBinding currentMethod, MethodBinding inheritedMethod) { if (isUnsafeReturnTypeOverride(currentMethod, inheritedMethod)) { problemReporter(currentMethod).unsafeReturnTypeOverride(currentMethod, inheritedMethod, this.type); return false; } return super.reportIncompatibleReturnTypeError(currentMethod, inheritedMethod); } void verify() { if (this.type.isAnnotationType()) this.type.detectAnnotationCycle(); super.verify(); reportRawReferences(); for (int i = this.type.typeVariables.length; --i >= 0;) { TypeVariableBinding var = this.type.typeVariables[i]; // must verify bounds if the variable has more than 1 if (var.superInterfaces == Binding.NO_SUPERINTERFACES) continue; if (var.superInterfaces.length == 1 && var.superclass.id == TypeIds.T_JavaLangObject) continue; this.currentMethods = new HashtableOfObject(0); ReferenceBinding superclass = var.superclass(); if (superclass.kind() == Binding.TYPE_PARAMETER) superclass = (ReferenceBinding) superclass.erasure(); ReferenceBinding[] itsInterfaces = var.superInterfaces(); ReferenceBinding[] superInterfaces = new ReferenceBinding[itsInterfaces.length]; for (int j = itsInterfaces.length; --j >= 0;) { superInterfaces[j] = itsInterfaces[j].kind() == Binding.TYPE_PARAMETER ? (ReferenceBinding) itsInterfaces[j].erasure() : itsInterfaces[j]; } computeInheritedMethods(superclass, superInterfaces); checkTypeVariableMethods(this.type.scope.referenceContext.typeParameters[i]); } } }