| /******************************************************************************* |
| * Copyright (c) 2000, 2010 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 <stephan@cs.tu-berlin.de> - Contribution for bug 282152 - [1.5][compiler] Generics code rejected by Eclipse but accepted by javac |
| *******************************************************************************/ |
| package org.eclipse.jdt.internal.compiler.lookup; |
| |
| import org.eclipse.jdt.core.compiler.CharOperation; |
| import org.eclipse.jdt.internal.compiler.ast.Wildcard; |
| import org.eclipse.jdt.internal.compiler.classfmt.ClassFileConstants; |
| |
| /** |
| * Binding for a type parameter, held by source/binary type or method. |
| */ |
| public class TypeVariableBinding extends ReferenceBinding { |
| |
| public Binding declaringElement; // binding of declaring type or method |
| public int rank; // declaration rank, can be used to match variable in parameterized type |
| |
| /** |
| * Denote the first explicit (binding) bound amongst the supertypes (from declaration in source) |
| * If no superclass was specified, then it denotes the first superinterface, or null if none was specified. |
| */ |
| public TypeBinding firstBound; |
| |
| // actual resolved variable supertypes (if no superclass bound, then associated to Object) |
| public ReferenceBinding superclass; |
| public ReferenceBinding[] superInterfaces; |
| public char[] genericTypeSignature; |
| LookupEnvironment environment; |
| |
| public TypeVariableBinding(char[] sourceName, Binding declaringElement, int rank, LookupEnvironment environment) { |
| this.sourceName = sourceName; |
| this.declaringElement = declaringElement; |
| this.rank = rank; |
| this.modifiers = ClassFileConstants.AccPublic | ExtraCompilerModifiers.AccGenericSignature; // treat type var as public |
| this.tagBits |= TagBits.HasTypeVariable; |
| this.environment = environment; |
| } |
| |
| /** |
| * Returns true if the argument type satisfies all bounds of the type parameter |
| */ |
| public int boundCheck(Substitution substitution, TypeBinding argumentType) { |
| if (argumentType == TypeBinding.NULL || argumentType == this) { |
| return TypeConstants.OK; |
| } |
| boolean hasSubstitution = substitution != null; |
| if (!(argumentType instanceof ReferenceBinding || argumentType.isArrayType())) |
| return TypeConstants.MISMATCH; |
| // special case for re-entrant source types (selection, code assist, etc)... |
| // can request additional types during hierarchy walk that are found as source types that also 'need' to connect their hierarchy |
| if (this.superclass == null) |
| return TypeConstants.OK; |
| |
| if (argumentType.kind() == Binding.WILDCARD_TYPE) { |
| WildcardBinding wildcard = (WildcardBinding) argumentType; |
| switch(wildcard.boundKind) { |
| case Wildcard.EXTENDS : |
| TypeBinding wildcardBound = wildcard.bound; |
| if (wildcardBound == this) |
| return TypeConstants.OK; |
| boolean isArrayBound = wildcardBound.isArrayType(); |
| if (!wildcardBound.isInterface()) { |
| TypeBinding substitutedSuperType = hasSubstitution ? Scope.substitute(substitution, this.superclass) : this.superclass; |
| if (substitutedSuperType.id != TypeIds.T_JavaLangObject) { |
| if (isArrayBound) { |
| if (!wildcardBound.isCompatibleWith(substitutedSuperType)) |
| return TypeConstants.MISMATCH; |
| } else { |
| TypeBinding match = wildcardBound.findSuperTypeOriginatingFrom(substitutedSuperType); |
| if (match != null) { |
| if (substitutedSuperType.isProvablyDistinct(match)) { |
| return TypeConstants.MISMATCH; |
| } |
| } else { |
| match = substitutedSuperType.findSuperTypeOriginatingFrom(wildcardBound); |
| if (match != null) { |
| if (match.isProvablyDistinct(wildcardBound)) { |
| return TypeConstants.MISMATCH; |
| } |
| } else { |
| if (!wildcardBound.isTypeVariable() && !substitutedSuperType.isTypeVariable()) { |
| return TypeConstants.MISMATCH; |
| } |
| } |
| } |
| } |
| } |
| } |
| boolean mustImplement = isArrayBound || ((ReferenceBinding)wildcardBound).isFinal(); |
| for (int i = 0, length = this.superInterfaces.length; i < length; i++) { |
| TypeBinding substitutedSuperType = hasSubstitution ? Scope.substitute(substitution, this.superInterfaces[i]) : this.superInterfaces[i]; |
| if (isArrayBound) { |
| if (!wildcardBound.isCompatibleWith(substitutedSuperType)) |
| return TypeConstants.MISMATCH; |
| } else { |
| TypeBinding match = wildcardBound.findSuperTypeOriginatingFrom(substitutedSuperType); |
| if (match != null) { |
| if (substitutedSuperType.isProvablyDistinct(match)) { |
| return TypeConstants.MISMATCH; |
| } |
| } else if (mustImplement) { |
| return TypeConstants.MISMATCH; // cannot be extended further to satisfy missing bounds |
| } |
| } |
| |
| } |
| break; |
| |
| case Wildcard.SUPER : |
| // if the wildcard is lower-bounded by a type variable that has no relevant upper bound there's nothing to check here (bug 282152): |
| if (wildcard.bound.isTypeVariable() && ((TypeVariableBinding)wildcard.bound).superclass.id == TypeIds.T_JavaLangObject) |
| break; |
| return boundCheck(substitution, wildcard.bound); |
| |
| case Wildcard.UNBOUND : |
| break; |
| } |
| return TypeConstants.OK; |
| } |
| boolean unchecked = false; |
| if (this.superclass.id != TypeIds.T_JavaLangObject) { |
| TypeBinding substitutedSuperType = hasSubstitution ? Scope.substitute(substitution, this.superclass) : this.superclass; |
| if (substitutedSuperType != argumentType) { |
| if (!argumentType.isCompatibleWith(substitutedSuperType)) { |
| return TypeConstants.MISMATCH; |
| } |
| TypeBinding match = argumentType.findSuperTypeOriginatingFrom(substitutedSuperType); |
| if (match != null){ |
| // Enum#RAW is not a substitute for <E extends Enum<E>> (86838) |
| if (match.isRawType() && substitutedSuperType.isBoundParameterizedType()) |
| unchecked = true; |
| } |
| } |
| } |
| for (int i = 0, length = this.superInterfaces.length; i < length; i++) { |
| TypeBinding substitutedSuperType = hasSubstitution ? Scope.substitute(substitution, this.superInterfaces[i]) : this.superInterfaces[i]; |
| if (substitutedSuperType != argumentType) { |
| if (!argumentType.isCompatibleWith(substitutedSuperType)) { |
| return TypeConstants.MISMATCH; |
| } |
| TypeBinding match = argumentType.findSuperTypeOriginatingFrom(substitutedSuperType); |
| if (match != null){ |
| // Enum#RAW is not a substitute for <E extends Enum<E>> (86838) |
| if (match.isRawType() && substitutedSuperType.isBoundParameterizedType()) |
| unchecked = true; |
| } |
| } |
| } |
| return unchecked ? TypeConstants.UNCHECKED : TypeConstants.OK; |
| } |
| |
| public int boundsCount() { |
| if (this.firstBound == null) { |
| return 0; |
| } else if (this.firstBound == this.superclass) { |
| return this.superInterfaces.length + 1; |
| } else { |
| return this.superInterfaces.length; |
| } |
| } |
| |
| /** |
| * @see org.eclipse.jdt.internal.compiler.lookup.ReferenceBinding#canBeInstantiated() |
| */ |
| public boolean canBeInstantiated() { |
| return false; |
| } |
| /** |
| * Collect the substitutes into a map for certain type variables inside the receiver type |
| * e.g. Collection<T>.collectSubstitutes(Collection<List<X>>, Map), will populate Map with: T --> List<X> |
| * Constraints: |
| * A << F corresponds to: F.collectSubstitutes(..., A, ..., CONSTRAINT_EXTENDS (1)) |
| * A = F corresponds to: F.collectSubstitutes(..., A, ..., CONSTRAINT_EQUAL (0)) |
| * A >> F corresponds to: F.collectSubstitutes(..., A, ..., CONSTRAINT_SUPER (2)) |
| */ |
| public void collectSubstitutes(Scope scope, TypeBinding actualType, InferenceContext inferenceContext, int constraint) { |
| |
| // only infer for type params of the generic method |
| if (this.declaringElement != inferenceContext.genericMethod) return; |
| |
| // cannot infer anything from a null type |
| switch (actualType.kind()) { |
| case Binding.BASE_TYPE : |
| if (actualType == TypeBinding.NULL) return; |
| TypeBinding boxedType = scope.environment().computeBoxingType(actualType); |
| if (boxedType == actualType) return; |
| actualType = boxedType; |
| break; |
| case Binding.WILDCARD_TYPE : |
| return; // wildcards are not true type expressions (JLS 15.12.2.7, p.453 2nd discussion) |
| } |
| |
| // reverse constraint, to reflect variable on rhs: A << T --> T >: A |
| int variableConstraint; |
| switch(constraint) { |
| case TypeConstants.CONSTRAINT_EQUAL : |
| variableConstraint = TypeConstants.CONSTRAINT_EQUAL; |
| break; |
| case TypeConstants.CONSTRAINT_EXTENDS : |
| variableConstraint = TypeConstants.CONSTRAINT_SUPER; |
| break; |
| default: |
| //case CONSTRAINT_SUPER : |
| variableConstraint =TypeConstants.CONSTRAINT_EXTENDS; |
| break; |
| } |
| inferenceContext.recordSubstitute(this, actualType, variableConstraint); |
| } |
| |
| /* |
| * declaringUniqueKey : genericTypeSignature |
| * p.X<T> { ... } --> Lp/X;:TT; |
| * p.X { <T> void foo() {...} } --> Lp/X;.foo()V:TT; |
| */ |
| public char[] computeUniqueKey(boolean isLeaf) { |
| StringBuffer buffer = new StringBuffer(); |
| Binding declaring = this.declaringElement; |
| if (!isLeaf && declaring.kind() == Binding.METHOD) { // see https://bugs.eclipse.org/bugs/show_bug.cgi?id=97902 |
| MethodBinding methodBinding = (MethodBinding) declaring; |
| ReferenceBinding declaringClass = methodBinding.declaringClass; |
| buffer.append(declaringClass.computeUniqueKey(false/*not a leaf*/)); |
| buffer.append(':'); |
| MethodBinding[] methods = declaringClass.methods(); |
| if (methods != null) |
| for (int i = 0, length = methods.length; i < length; i++) { |
| MethodBinding binding = methods[i]; |
| if (binding == methodBinding) { |
| buffer.append(i); |
| break; |
| } |
| } |
| } else { |
| buffer.append(declaring.computeUniqueKey(false/*not a leaf*/)); |
| buffer.append(':'); |
| } |
| buffer.append(genericTypeSignature()); |
| int length = buffer.length(); |
| char[] uniqueKey = new char[length]; |
| buffer.getChars(0, length, uniqueKey, 0); |
| return uniqueKey; |
| } |
| public char[] constantPoolName() { /* java/lang/Object */ |
| if (this.firstBound != null) { |
| return this.firstBound.constantPoolName(); |
| } |
| return this.superclass.constantPoolName(); // java/lang/Object |
| } |
| /** |
| * @see org.eclipse.jdt.internal.compiler.lookup.TypeBinding#debugName() |
| */ |
| public String debugName() { |
| return new String(this.sourceName); |
| } |
| public TypeBinding erasure() { |
| if (this.firstBound != null) { |
| return this.firstBound.erasure(); |
| } |
| return this.superclass; // java/lang/Object |
| } |
| /** |
| * T::Ljava/util/Map;:Ljava/io/Serializable; |
| * T:LY<TT;> |
| */ |
| public char[] genericSignature() { |
| StringBuffer sig = new StringBuffer(10); |
| sig.append(this.sourceName).append(':'); |
| int interfaceLength = this.superInterfaces == null ? 0 : this.superInterfaces.length; |
| if (interfaceLength == 0 || this.firstBound == this.superclass) { |
| if (this.superclass != null) |
| sig.append(this.superclass.genericTypeSignature()); |
| } |
| for (int i = 0; i < interfaceLength; i++) { |
| sig.append(':').append(this.superInterfaces[i].genericTypeSignature()); |
| } |
| int sigLength = sig.length(); |
| char[] genericSignature = new char[sigLength]; |
| sig.getChars(0, sigLength, genericSignature, 0); |
| return genericSignature; |
| } |
| /** |
| * T::Ljava/util/Map;:Ljava/io/Serializable; |
| * T:LY<TT;> |
| */ |
| public char[] genericTypeSignature() { |
| if (this.genericTypeSignature != null) return this.genericTypeSignature; |
| return this.genericTypeSignature = CharOperation.concat('T', this.sourceName, ';'); |
| } |
| |
| boolean hasOnlyRawBounds() { |
| if (this.superclass != null && this.firstBound == this.superclass) |
| if (!this.superclass.isRawType()) |
| return false; |
| |
| if (this.superInterfaces != null) |
| for (int i = 0, l = this.superInterfaces.length; i < l; i++) |
| if (!this.superInterfaces[i].isRawType()) |
| return false; |
| |
| return true; |
| } |
| |
| /** |
| * Returns true if the type variable is directly bound to a given type |
| */ |
| public boolean isErasureBoundTo(TypeBinding type) { |
| if (this.superclass.erasure() == type) |
| return true; |
| for (int i = 0, length = this.superInterfaces.length; i < length; i++) { |
| if (this.superInterfaces[i].erasure() == type) |
| return true; |
| } |
| return false; |
| } |
| |
| public boolean isHierarchyConnected() { |
| return (this.modifiers & ExtraCompilerModifiers.AccUnresolved) == 0; |
| } |
| |
| /** |
| * Returns true if the 2 variables are playing exact same role: they have |
| * the same bounds, providing one is substituted with the other: <T1 extends |
| * List<T1>> is interchangeable with <T2 extends List<T2>>. |
| */ |
| public boolean isInterchangeableWith(TypeVariableBinding otherVariable, Substitution substitute) { |
| if (this == otherVariable) |
| return true; |
| int length = this.superInterfaces.length; |
| if (length != otherVariable.superInterfaces.length) |
| return false; |
| |
| if (this.superclass != Scope.substitute(substitute, otherVariable.superclass)) |
| return false; |
| |
| next : for (int i = 0; i < length; i++) { |
| TypeBinding superType = Scope.substitute(substitute, otherVariable.superInterfaces[i]); |
| for (int j = 0; j < length; j++) |
| if (superType == this.superInterfaces[j]) |
| continue next; |
| return false; // not a match |
| } |
| return true; |
| } |
| |
| /** |
| * Returns true if the type was declared as a type variable |
| */ |
| public boolean isTypeVariable() { |
| return true; |
| } |
| |
| // /** |
| // * Returns the original type variable for a given variable. |
| // * Only different from receiver for type variables of generic methods of parameterized types |
| // * e.g. X<U> { <V1 extends U> U foo(V1) } --> X<String> { <V2 extends String> String foo(V2) } |
| // * and V2.original() --> V1 |
| // */ |
| // public TypeVariableBinding original() { |
| // if (this.declaringElement.kind() == Binding.METHOD) { |
| // MethodBinding originalMethod = ((MethodBinding)this.declaringElement).original(); |
| // if (originalMethod != this.declaringElement) { |
| // return originalMethod.typeVariables[this.rank]; |
| // } |
| // } else { |
| // ReferenceBinding originalType = (ReferenceBinding)((ReferenceBinding)this.declaringElement).erasure(); |
| // if (originalType != this.declaringElement) { |
| // return originalType.typeVariables()[this.rank]; |
| // } |
| // } |
| // return this; |
| // } |
| |
| public int kind() { |
| return Binding.TYPE_PARAMETER; |
| } |
| |
| public TypeBinding[] otherUpperBounds() { |
| if (this.firstBound == null) |
| return Binding.NO_TYPES; |
| if (this.firstBound == this.superclass) |
| return this.superInterfaces; |
| int otherLength = this.superInterfaces.length - 1; |
| if (otherLength > 0) { |
| TypeBinding[] otherBounds; |
| System.arraycopy(this.superInterfaces, 1, otherBounds = new TypeBinding[otherLength], 0, otherLength); |
| return otherBounds; |
| } |
| return Binding.NO_TYPES; |
| } |
| |
| /** |
| * @see org.eclipse.jdt.internal.compiler.lookup.ReferenceBinding#readableName() |
| */ |
| public char[] readableName() { |
| return this.sourceName; |
| } |
| ReferenceBinding resolve() { |
| if ((this.modifiers & ExtraCompilerModifiers.AccUnresolved) == 0) |
| return this; |
| |
| TypeBinding oldSuperclass = this.superclass, oldFirstInterface = null; |
| if (this.superclass != null) { |
| ReferenceBinding resolveType = (ReferenceBinding) BinaryTypeBinding.resolveType(this.superclass, this.environment, true /* raw conversion */); |
| this.tagBits |= resolveType.tagBits & TagBits.ContainsNestedTypeReferences; |
| this.superclass = resolveType; |
| } |
| ReferenceBinding[] interfaces = this.superInterfaces; |
| int length; |
| if ((length = interfaces.length) != 0) { |
| oldFirstInterface = interfaces[0]; |
| for (int i = length; --i >= 0;) { |
| ReferenceBinding resolveType = (ReferenceBinding) BinaryTypeBinding.resolveType(interfaces[i], this.environment, true /* raw conversion */); |
| this.tagBits |= resolveType.tagBits & TagBits.ContainsNestedTypeReferences; |
| interfaces[i] = resolveType; |
| } |
| } |
| // refresh the firstBound in case it changed |
| if (this.firstBound != null) { |
| if (this.firstBound == oldSuperclass) { |
| this.firstBound = this.superclass; |
| } else if (this.firstBound == oldFirstInterface) { |
| this.firstBound = interfaces[0]; |
| } |
| } |
| this.modifiers &= ~ExtraCompilerModifiers.AccUnresolved; |
| return this; |
| } |
| /** |
| * @see org.eclipse.jdt.internal.compiler.lookup.ReferenceBinding#shortReadableName() |
| */ |
| public char[] shortReadableName() { |
| return readableName(); |
| } |
| public ReferenceBinding superclass() { |
| return this.superclass; |
| } |
| |
| public ReferenceBinding[] superInterfaces() { |
| return this.superInterfaces; |
| } |
| |
| /** |
| * @see java.lang.Object#toString() |
| */ |
| public String toString() { |
| StringBuffer buffer = new StringBuffer(10); |
| buffer.append('<').append(this.sourceName);//.append('[').append(this.rank).append(']'); |
| if (this.superclass != null && this.firstBound == this.superclass) { |
| buffer.append(" extends ").append(this.superclass.debugName()); //$NON-NLS-1$ |
| } |
| if (this.superInterfaces != null && this.superInterfaces != Binding.NO_SUPERINTERFACES) { |
| if (this.firstBound != this.superclass) { |
| buffer.append(" extends "); //$NON-NLS-1$ |
| } |
| for (int i = 0, length = this.superInterfaces.length; i < length; i++) { |
| if (i > 0 || this.firstBound == this.superclass) { |
| buffer.append(" & "); //$NON-NLS-1$ |
| } |
| buffer.append(this.superInterfaces[i].debugName()); |
| } |
| } |
| buffer.append('>'); |
| return buffer.toString(); |
| } |
| |
| /** |
| * Upper bound doesn't perform erasure |
| */ |
| public TypeBinding upperBound() { |
| if (this.firstBound != null) { |
| return this.firstBound; |
| } |
| return this.superclass; // java/lang/Object |
| } |
| } |
