| /******************************************************************************* |
| * Copyright (c) 2000, 2005 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 |
| *******************************************************************************/ |
| package org.eclipse.jdt.internal.compiler.lookup; |
| |
| import java.util.Map; |
| import org.eclipse.jdt.core.compiler.CharOperation; |
| import org.eclipse.jdt.internal.compiler.ast.Wildcard; |
| |
| /** |
| * 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; |
| |
| public TypeVariableBinding(char[] sourceName, Binding declaringElement, int rank) { |
| this.sourceName = sourceName; |
| this.declaringElement = declaringElement; |
| this.rank = rank; |
| this.modifiers = AccPublic | AccGenericSignature; // treat type var as public |
| this.tagBits |= HasTypeVariable; |
| } |
| |
| public int kind() { |
| return TYPE_PARAMETER; |
| } |
| |
| /** |
| * Returns true if the argument type satisfies all bounds of the type parameter |
| */ |
| public int boundCheck(Substitution substitution, TypeBinding argumentType) { |
| |
| if (argumentType == NullBinding || 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.isWildcard() && !argumentType.isIntersectionType()) { |
| WildcardBinding wildcard = (WildcardBinding) argumentType; |
| switch(wildcard.boundKind) { |
| case Wildcard.EXTENDS : |
| TypeBinding wildcardBound = wildcard.bound; |
| if (wildcardBound == this) |
| return TypeConstants.OK; |
| ReferenceBinding superclassBound = hasSubstitution ? (ReferenceBinding)Scope.substitute(substitution, this.superclass) : this.superclass; |
| boolean isArrayBound = wildcardBound.isArrayType(); |
| if (!wildcardBound.isInterface()) { |
| if (superclassBound.id != T_JavaLangObject) { |
| if (isArrayBound) { |
| if (!wildcardBound.isCompatibleWith(superclassBound)) |
| return TypeConstants.MISMATCH; |
| } else { |
| ReferenceBinding match = ((ReferenceBinding)wildcardBound).findSuperTypeWithSameErasure(superclassBound); |
| if (match != null) { |
| if (!match.isIntersectingWith(superclassBound)) { |
| return TypeConstants.MISMATCH; |
| } |
| } else { |
| return TypeConstants.MISMATCH; |
| } |
| } |
| } |
| } |
| ReferenceBinding[] superInterfaceBounds = hasSubstitution ? Scope.substitute(substitution, this.superInterfaces) : this.superInterfaces; |
| int length = superInterfaceBounds.length; |
| boolean mustImplement = isArrayBound || ((ReferenceBinding)wildcardBound).isFinal(); |
| for (int i = 0; i < length; i++) { |
| TypeBinding superInterfaceBound = superInterfaceBounds[i]; |
| if (isArrayBound) { |
| if (!wildcardBound.isCompatibleWith(superInterfaceBound)) |
| return TypeConstants.MISMATCH; |
| } else { |
| ReferenceBinding match = ((ReferenceBinding)wildcardBound).findSuperTypeWithSameErasure(superInterfaceBound); |
| if (match != null) { |
| if (!match.isIntersectingWith(superInterfaceBound)) { |
| return TypeConstants.MISMATCH; |
| } |
| } else if (mustImplement) { |
| return TypeConstants.MISMATCH; // cannot be extended further to satisfy missing bounds |
| } |
| } |
| |
| } |
| break; |
| |
| case Wildcard.SUPER : |
| return boundCheck(substitution, wildcard.bound); |
| |
| case Wildcard.UNBOUND : |
| break; |
| } |
| return TypeConstants.OK; |
| } |
| boolean unchecked = false; |
| if (this.superclass.id != T_JavaLangObject) { |
| TypeBinding superType = this.superclass; |
| if (superType != argumentType) { // check identity before substituting (104649) |
| TypeBinding substitutedSuperType = hasSubstitution ? Scope.substitute(substitution, superType) : superType; |
| if (!argumentType.isCompatibleWith(substitutedSuperType)) { |
| return TypeConstants.MISMATCH; |
| } |
| if (argumentType instanceof ReferenceBinding) { |
| ReferenceBinding referenceArgument = (ReferenceBinding) argumentType; |
| TypeBinding match = referenceArgument.findSuperTypeWithSameErasure(substitutedSuperType); |
| if (match != null){ |
| // Enum#RAW is not a substitute for <E extends Enum<E>> (86838) |
| if (match.isRawType() && (substitutedSuperType.isGenericType()||substitutedSuperType.isBoundParameterizedType())) |
| unchecked = true; |
| } |
| } |
| } |
| } |
| for (int i = 0, length = this.superInterfaces.length; i < length; i++) { |
| TypeBinding superType = this.superInterfaces[i]; |
| if (superType != argumentType) { // check identity before substituting (104649) |
| TypeBinding substitutedSuperType = hasSubstitution ? Scope.substitute(substitution, superType) : superType; |
| if (!argumentType.isCompatibleWith(substitutedSuperType)) { |
| return TypeConstants.MISMATCH; |
| } |
| if (argumentType instanceof ReferenceBinding) { |
| ReferenceBinding referenceArgument = (ReferenceBinding) argumentType; |
| TypeBinding match = referenceArgument.findSuperTypeWithSameErasure(substitutedSuperType); |
| if (match != null){ |
| // Enum#RAW is not a substitute for <E extends Enum<E>> (86838) |
| if (match.isRawType() && (substitutedSuperType.isGenericType()||substitutedSuperType.isBoundParameterizedType())) |
| unchecked = true; |
| } |
| } |
| } |
| } |
| return unchecked ? TypeConstants.UNCHECKED : TypeConstants.OK; |
| } |
| |
| /** |
| * @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> |
| */ |
| public void collectSubstitutes(Scope scope, TypeBinding otherType, Map substitutes, int constraint) { |
| |
| // cannot infer anything from a null type |
| switch (otherType.kind()) { |
| case Binding.BASE_TYPE : |
| if (otherType == NullBinding) return; |
| TypeBinding boxedType = scope.environment().computeBoxingType(otherType); |
| if (boxedType == otherType) return; |
| otherType = boxedType; |
| break; |
| case Binding.WILDCARD_TYPE : |
| WildcardBinding otherWildcard = (WildcardBinding) otherType; |
| if (otherWildcard.otherBounds != null) break; // intersection 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 CONSTRAINT_EQUAL : |
| variableConstraint = CONSTRAINT_EQUAL; |
| break; |
| case CONSTRAINT_EXTENDS : |
| variableConstraint = CONSTRAINT_SUPER; |
| break; |
| default: |
| //case CONSTRAINT_SUPER : |
| variableConstraint = CONSTRAINT_EXTENDS; |
| break; |
| } |
| TypeBinding[][] variableSubstitutes = (TypeBinding[][])substitutes.get(this); |
| if (variableSubstitutes != null) { |
| insertLoop: { |
| TypeBinding[] constraintSubstitutes = variableSubstitutes[variableConstraint]; |
| int length; |
| if (constraintSubstitutes == null) { |
| length = 0; |
| constraintSubstitutes = new TypeBinding[1]; |
| } else { |
| length = constraintSubstitutes.length; |
| for (int i = 0; i < length; i++) { |
| TypeBinding substitute = constraintSubstitutes[i]; |
| if (substitute == otherType) return; // already there |
| if (substitute == null) { |
| constraintSubstitutes[i] = otherType; |
| break insertLoop; |
| } |
| } |
| // no free spot found, need to grow |
| System.arraycopy(constraintSubstitutes, 0, constraintSubstitutes = new TypeBinding[2*length], 0, length); |
| } |
| constraintSubstitutes[length] = otherType; |
| variableSubstitutes[variableConstraint] = constraintSubstitutes; |
| } |
| } |
| } |
| |
| public char[] constantPoolName() { /* java/lang/Object */ |
| if (this.firstBound != null) { |
| return this.firstBound.constantPoolName(); |
| } |
| return this.superclass.constantPoolName(); // java/lang/Object |
| } |
| /* |
| * 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; |
| } |
| /** |
| * @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.length; |
| if (interfaceLength == 0 || this.firstBound == this.superclass) { |
| 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, ';'); |
| } |
| |
| /** |
| * 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; |
| } |
| |
| /** |
| * 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(final LookupEnvironment environment, final TypeVariableBinding otherVariable) { |
| if (this == otherVariable) |
| return true; |
| int length = this.superInterfaces.length; |
| if (length != otherVariable.superInterfaces.length) |
| return false; |
| |
| identical: { |
| if (this.superclass != otherVariable.superclass) { |
| if (this.superclass.erasure() != otherVariable.superclass.erasure()) |
| return false; // no way it can match after substitution |
| break identical; |
| } |
| for (int i = 0; i < length; i++) { |
| if (this.superInterfaces[i] != otherVariable.superInterfaces[i]) { |
| if (this.superInterfaces[i].erasure() != otherVariable.superInterfaces[i].erasure()) |
| return false; // no way it can match after substitution |
| break identical; |
| } |
| } |
| return true; |
| } |
| // need substitutions |
| Substitution subst = new Substitution() { |
| public LookupEnvironment environment() { return environment; } |
| public boolean isRawSubstitution() { return false; } |
| public TypeBinding substitute(TypeVariableBinding typeVariable) { |
| return typeVariable == otherVariable ? TypeVariableBinding.this : typeVariable; |
| } |
| }; |
| if (this.superclass != Scope.substitute(subst, otherVariable.superclass)) |
| return false; |
| for (int i = 0; i < length; i++) |
| if (this.superInterfaces[i] != Scope.substitute(subst, otherVariable.superInterfaces[i])) |
| return false; |
| 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; |
| } |
| |
| /** |
| * @see org.eclipse.jdt.internal.compiler.lookup.ReferenceBinding#readableName() |
| */ |
| public char[] readableName() { |
| return this.sourceName; |
| } |
| |
| ReferenceBinding resolve(LookupEnvironment environment) { |
| if ((this.modifiers & AccUnresolved) == 0) |
| return this; |
| |
| TypeBinding oldSuperclass = this.superclass, oldFirstInterface = null; |
| if (this.superclass != null) |
| this.superclass = BinaryTypeBinding.resolveUnresolvedType(this.superclass, environment, true); |
| ReferenceBinding[] interfaces = this.superInterfaces; |
| int length; |
| if ((length = interfaces.length) != 0) { |
| oldFirstInterface = interfaces[0]; |
| for (int i = length; --i >= 0;) { |
| interfaces[i] = BinaryTypeBinding.resolveUnresolvedType(interfaces[i], environment, true); |
| } |
| } |
| this.modifiers &= ~AccUnresolved; |
| |
| // finish resolving the types |
| if (this.superclass != null) |
| this.superclass = BinaryTypeBinding.resolveType(this.superclass, environment, true); |
| for (int i = interfaces.length; --i >= 0;) |
| interfaces[i] = BinaryTypeBinding.resolveType(interfaces[i], environment, true); |
| |
| // 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]; |
| } |
| } |
| return this; |
| } |
| |
| /** |
| * @see org.eclipse.jdt.internal.compiler.lookup.ReferenceBinding#shortReadableName() |
| */ |
| public char[] shortReadableName() { |
| return this.readableName(); |
| } |
| public ReferenceBinding superclass() { |
| return superclass; |
| } |
| public ReferenceBinding[] superInterfaces() { |
| return 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 != NoSuperInterfaces) { |
| 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 |
| } |
| } |