Copyright (c) 2013, 2019 GK Software AG. This program and the accompanying materials are made available under the terms of the Eclipse Public License 2.0 which accompanies this distribution, and is available at https://www.eclipse.org/legal/epl-2.0/ SPDX-License-Identifier: EPL-2.0 Contributors: Stephan Herrmann - initial API and implementation
/******************************************************************************* * Copyright (c) 2013, 2019 GK Software AG. * * This program and the accompanying materials * are made available under the terms of the Eclipse Public License 2.0 * which accompanies this distribution, and is available at * https://www.eclipse.org/legal/epl-2.0/ * * SPDX-License-Identifier: EPL-2.0 * * Contributors: * Stephan Herrmann - initial API and implementation *******************************************************************************/
package org.eclipse.jdt.internal.compiler.lookup; import org.eclipse.jdt.core.compiler.CharOperation; import org.eclipse.jdt.internal.compiler.ast.Wildcard;
Capture-like type variable introduced during 1.8 type inference.
/** * Capture-like type variable introduced during 1.8 type inference. */
public class CaptureBinding18 extends CaptureBinding { TypeBinding[] upperBounds; private char[] originalName; private CaptureBinding18 prototype; public CaptureBinding18(ReferenceBinding contextType, char[] sourceName, char[] originalName, int start, int end, int captureID, LookupEnvironment environment) { super(contextType, sourceName, start, end, captureID, environment); this.originalName = originalName; this.prototype = this; } private CaptureBinding18(CaptureBinding18 prototype) { super(prototype); this.sourceName = CharOperation.append(prototype.sourceName, '\''); this.originalName = prototype.originalName; this.upperBounds = prototype.upperBounds; this.prototype = prototype.prototype; } public boolean setUpperBounds(TypeBinding[] upperBounds, ReferenceBinding javaLangObject) { this.upperBounds = upperBounds; if (upperBounds.length > 0) this.firstBound = upperBounds[0]; int numReferenceInterfaces = 0; if (!isConsistentIntersection(upperBounds)) return false; for (int i = 0; i < upperBounds.length; i++) { TypeBinding aBound = upperBounds[i]; if (aBound instanceof ReferenceBinding) { if (this.superclass == null && aBound.isClass()) this.superclass = (ReferenceBinding) aBound; else if (aBound.isInterface()) numReferenceInterfaces++; } else if (TypeBinding.equalsEquals(aBound.leafComponentType(), this)) { return false; // cycle detected } } this.superInterfaces = new ReferenceBinding[numReferenceInterfaces]; int idx = 0; for (int i = 0; i < upperBounds.length; i++) { TypeBinding aBound = upperBounds[i]; if (aBound.isInterface()) this.superInterfaces[idx++] = (ReferenceBinding) aBound; } if (this.superclass == null) this.superclass = javaLangObject; return true; } @Override public void initializeBounds(Scope scope, ParameterizedTypeBinding capturedParameterizedType) { // nothing to initialize here (and cannot use super methods which requires wildcard to be set). } @Override public TypeBinding clone(TypeBinding enclosingType) { return new CaptureBinding18(this); } @Override public MethodBinding[] getMethods(char[] selector) { if (this.upperBounds.length == 1 && this.upperBounds[0] instanceof ReferenceBinding) return ((ReferenceBinding)this.upperBounds[0]).getMethods(selector); return super.getMethods(selector); } @Override public TypeBinding erasure() { if (this.upperBounds != null && this.upperBounds.length > 1) { ReferenceBinding[] erasures = new ReferenceBinding[this.upperBounds.length]; boolean multipleErasures = false; for (int i = 0; i < this.upperBounds.length; i++) { erasures[i] = (ReferenceBinding) this.upperBounds[i].erasure(); // FIXME cast? if (i > 0) { if (TypeBinding.notEquals(erasures[0], erasures[i])) multipleErasures = true; } } if (!multipleErasures) return erasures[0]; return this.environment.createIntersectionType18(erasures); } if (this.superclass == null) return this.environment.getType(TypeConstants.JAVA_LANG_OBJECT); return super.erasure(); }
See Also:
  • isEquivalentTo.isEquivalentTo(TypeBinding)
/** * @see TypeBinding#isEquivalentTo(TypeBinding) */
@Override public boolean isEquivalentTo(TypeBinding otherType) { // from CaptureBinding: if (equalsEquals(this, otherType)) return true; if (otherType == null) return false; if (this.upperBounds != null) { // from CaptureBinding: for (int i = 0; i < this.upperBounds.length; i++) { TypeBinding aBound = this.upperBounds[i]; // capture of ? extends X[] if (aBound != null && aBound.isArrayType()) { if (!aBound.isCompatibleWith(otherType)) return false; } else switch (otherType.kind()) { case Binding.WILDCARD_TYPE : case Binding.INTERSECTION_TYPE : if (!((WildcardBinding) otherType).boundCheck(aBound)) return false; } } return true; } return false; } @Override public boolean isCompatibleWith(TypeBinding otherType, Scope captureScope) { if (TypeBinding.equalsEquals(this, otherType)) return true; if (this.inRecursiveFunction) return true; this.inRecursiveFunction = true; try { if (this.upperBounds != null) { int length = this.upperBounds.length; // need to compare two intersection types? (borrowed from IntersectionType18) int rightKind = otherType.kind(); TypeBinding[] rightIntersectingTypes = null; if (rightKind == INTERSECTION_TYPE && otherType.boundKind() == Wildcard.EXTENDS) { TypeBinding allRightBounds = ((WildcardBinding) otherType).allBounds(); if (allRightBounds instanceof IntersectionTypeBinding18) rightIntersectingTypes = ((IntersectionTypeBinding18) allRightBounds).intersectingTypes; } else if (rightKind == INTERSECTION_TYPE18) { rightIntersectingTypes = ((IntersectionTypeBinding18) otherType).intersectingTypes; } if (rightIntersectingTypes != null) { nextRequired: for (TypeBinding required : rightIntersectingTypes) { for (TypeBinding provided : this.upperBounds) { if (provided.isCompatibleWith(required, captureScope)) continue nextRequired; } return false; } return true; } for (int i = 0; i < length; i++) { if (this.upperBounds[i].isCompatibleWith(otherType, captureScope)) return true; } } return false; } finally { this.inRecursiveFunction = false; } } @Override public TypeBinding findSuperTypeOriginatingFrom(TypeBinding otherType) { if (this.upperBounds != null && this.upperBounds.length > 1) { for (int i = 0; i < this.upperBounds.length; i++) { TypeBinding candidate = this.upperBounds[i].findSuperTypeOriginatingFrom(otherType); if (candidate != null) return candidate; // TODO: maybe we should double check about multiple candidates here, // but upper bounds should be consistent so hopefully the first non-null candidate is good enough. } } return super.findSuperTypeOriginatingFrom(otherType); } @Override TypeBinding substituteInferenceVariable(InferenceVariable var, TypeBinding substituteType) { if (this.inRecursiveFunction) return this; this.inRecursiveFunction = true; try { boolean haveSubstitution = false; ReferenceBinding currentSuperclass = this.superclass; if (currentSuperclass != null) { currentSuperclass = (ReferenceBinding) currentSuperclass.substituteInferenceVariable(var, substituteType); haveSubstitution |= TypeBinding.notEquals(currentSuperclass, this.superclass); } ReferenceBinding[] currentSuperInterfaces = null; if (this.superInterfaces != null) { int length = this.superInterfaces.length; if (haveSubstitution) System.arraycopy(this.superInterfaces, 0, currentSuperInterfaces=new ReferenceBinding[length], 0, length); for (int i = 0; i < length; i++) { ReferenceBinding currentSuperInterface = this.superInterfaces[i]; if (currentSuperInterface != null) { currentSuperInterface = (ReferenceBinding) currentSuperInterface.substituteInferenceVariable(var, substituteType); if (TypeBinding.notEquals(currentSuperInterface, this.superInterfaces[i])) { if (currentSuperInterfaces == null) System.arraycopy(this.superInterfaces, 0, currentSuperInterfaces=new ReferenceBinding[length], 0, length); currentSuperInterfaces[i] = currentSuperInterface; haveSubstitution = true; } } } } TypeBinding[] currentUpperBounds = null; if (this.upperBounds != null) { int length = this.upperBounds.length; if (haveSubstitution) System.arraycopy(this.upperBounds, 0, currentUpperBounds=new TypeBinding[length], 0, length); for (int i = 0; i < length; i++) { TypeBinding currentBound = this.upperBounds[i]; if (currentBound != null) { currentBound = currentBound.substituteInferenceVariable(var, substituteType); if (TypeBinding.notEquals(currentBound, this.upperBounds[i])) { if (currentUpperBounds == null) System.arraycopy(this.upperBounds, 0, currentUpperBounds=new TypeBinding[length], 0, length); currentUpperBounds[i] = currentBound; haveSubstitution = true; } } } } TypeBinding currentFirstBound = null; if (this.firstBound != null) { currentFirstBound = this.firstBound.substituteInferenceVariable(var, substituteType); haveSubstitution |= TypeBinding.notEquals(this.firstBound, currentFirstBound); } if (haveSubstitution) { final CaptureBinding18 newCapture = (CaptureBinding18) clone(enclosingType()); newCapture.tagBits = this.tagBits; Substitution substitution = new Substitution() { @Override public TypeBinding substitute(TypeVariableBinding typeVariable) { return (typeVariable == CaptureBinding18.this) ? newCapture : typeVariable; //$IDENTITY-COMPARISON$ } @Override public boolean isRawSubstitution() { return false; } @Override public LookupEnvironment environment() { return CaptureBinding18.this.environment; } }; if (currentFirstBound != null) newCapture.firstBound = Scope.substitute(substitution, currentFirstBound); newCapture.superclass = (ReferenceBinding) Scope.substitute(substitution, currentSuperclass); newCapture.superInterfaces = Scope.substitute(substitution, currentSuperInterfaces); newCapture.upperBounds = Scope.substitute(substitution, currentUpperBounds); return newCapture; } return this; } finally { this.inRecursiveFunction = false; } } @Override public boolean isProperType(boolean admitCapture18) { if (!admitCapture18) return false; if (this.inRecursiveFunction) return true; this.inRecursiveFunction = true; try { if (this.lowerBound != null && !this.lowerBound.isProperType(admitCapture18)) return false; if (this.upperBounds != null) { for (int i = 0; i < this.upperBounds.length; i++) { if (!this.upperBounds[i].isProperType(admitCapture18)) return false; } } } finally { this.inRecursiveFunction = false; } return true; } int recursionLevel = 0; // used to give a hint at recursive types without going into infinity @Override public char[] readableName() { if (this.lowerBound == null && this.firstBound != null) { if (this.prototype.recursionLevel < 2) { try { this.prototype.recursionLevel ++; if (this.upperBounds != null && this.upperBounds.length > 1) { StringBuffer sb = new StringBuffer(); sb.append(this.upperBounds[0].readableName()); for (int i = 1; i < this.upperBounds.length; i++) sb.append('&').append(this.upperBounds[i].readableName()); int len = sb.length(); char[] name = new char[len]; sb.getChars(0, len, name, 0); return name; } return this.firstBound.readableName(); } finally { this.prototype.recursionLevel--; } } else { return this.originalName; } } return super.readableName(); } @Override public char[] shortReadableName() { if (this.lowerBound == null && this.firstBound != null) { if (this.prototype.recursionLevel < 2) { try { this.prototype.recursionLevel++; if (this.upperBounds != null && this.upperBounds.length > 1) { StringBuffer sb = new StringBuffer(); sb.append(this.upperBounds[0].shortReadableName()); for (int i = 1; i < this.upperBounds.length; i++) sb.append('&').append(this.upperBounds[i].shortReadableName()); int len = sb.length(); char[] name = new char[len]; sb.getChars(0, len, name, 0); return name; } return this.firstBound.shortReadableName(); } finally { this.prototype.recursionLevel--; } } else { return this.originalName; } } return super.shortReadableName(); } @Override public TypeBinding uncapture(Scope scope) { return this; } @Override public char[] computeUniqueKey(boolean isLeaf) { StringBuffer buffer = new StringBuffer(); buffer.append(TypeConstants.CAPTURE18); buffer.append('{').append(this.end).append('#').append(this.captureID).append('}'); buffer.append(';'); int length = buffer.length(); char[] uniqueKey = new char[length]; buffer.getChars(0, length, uniqueKey, 0); return uniqueKey; } }