/*******************************************************************************
* 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 <stephan@cs.tu-berlin.de> - Contributions for
* bug 185682 - Increment/decrement operators mark local variables as read
* bug 349326 - [1.7] new warning for missing try-with-resources
* bug 186342 - [compiler][null] Using annotations for null checking
* bug 365859 - [compiler][null] distinguish warnings based on flow analysis vs. null annotations
* bug 331649 - [compiler][null] consider null annotations for fields
*******************************************************************************/
package org.eclipse.jdt.internal.compiler.lookup;
import org.eclipse.jdt.core.compiler.CharOperation;
import org.eclipse.jdt.internal.compiler.ast.ASTNode;
import org.eclipse.jdt.internal.compiler.ast.AbstractMethodDeclaration;
import org.eclipse.jdt.internal.compiler.ast.Annotation;
import org.eclipse.jdt.internal.compiler.ast.FakedTrackingVariable;
import org.eclipse.jdt.internal.compiler.ast.LambdaExpression;
import org.eclipse.jdt.internal.compiler.ast.LocalDeclaration;
import org.eclipse.jdt.internal.compiler.ast.TypeDeclaration;
import org.eclipse.jdt.internal.compiler.impl.Constant;
import org.eclipse.jdt.internal.compiler.impl.ReferenceContext;
public class LocalVariableBinding extends VariableBinding {
public int resolvedPosition; // for code generation (position in method context)
public static final int UNUSED = 0;
public static final int USED = 1;
public static final int FAKE_USED = 2;
public int useFlag; // for flow analysis (default is UNUSED), values < 0 indicate the number of compound uses (postIncrement or compoundAssignment)
public BlockScope declaringScope; // back-pointer to its declaring scope
public LocalDeclaration declaration; // for source-positions
public int[] initializationPCs;
public int initializationCount = 0;
public FakedTrackingVariable closeTracker; // track closing of instances of type AutoCloseable, maybe null
// for synthetic local variables
// if declaration slot is not positionned, the variable will not be listed in attribute
// note that the name of a variable should be chosen so as not to conflict with user ones (usually starting with a space char is all needed)
public LocalVariableBinding(char[] name, TypeBinding type, int modifiers, boolean isArgument) {
super(name, type, modifiers, isArgument ? Constant.NotAConstant : null);
if (isArgument) this.tagBits |= TagBits.IsArgument;
this.tagBits |= TagBits.IsEffectivelyFinal;
}
// regular local variable or argument
public LocalVariableBinding(LocalDeclaration declaration, TypeBinding type, int modifiers, boolean isArgument) {
this(declaration.name, type, modifiers, isArgument);
this.declaration = declaration;
}
// argument
public LocalVariableBinding(LocalDeclaration declaration, TypeBinding type, int modifiers, MethodScope declaringScope) {
this(declaration, type, modifiers, true);
this.declaringScope = declaringScope;
}
/* API
* Answer the receiver's binding type from Binding.BindingID.
*/
public final int kind() {
return LOCAL;
}
/*
* declaringUniqueKey # scopeIndex(0-based) # varName [# occurrenceCount(0-based)]
* p.X { void foo() { int local; int local;} } --> Lp/X;.foo()V#1#local#1
*/
public char[] computeUniqueKey(boolean isLeaf) {
StringBuffer buffer = new StringBuffer();
// declaring method or type
BlockScope scope = this.declaringScope;
int occurenceCount = 0;
if (scope != null) {
// the scope can be null. See https://bugs.eclipse.org/bugs/show_bug.cgi?id=185129
MethodScope methodScope = scope instanceof MethodScope ? (MethodScope) scope : scope.enclosingMethodScope();
ReferenceContext referenceContext = methodScope.referenceContext;
if (referenceContext instanceof AbstractMethodDeclaration) {
MethodBinding methodBinding = ((AbstractMethodDeclaration) referenceContext).binding;
if (methodBinding != null) {
buffer.append(methodBinding.computeUniqueKey(false/*not a leaf*/));
}
} else if (referenceContext instanceof TypeDeclaration) {
TypeBinding typeBinding = ((TypeDeclaration) referenceContext).binding;
if (typeBinding != null) {
buffer.append(typeBinding.computeUniqueKey(false/*not a leaf*/));
}
} else if (referenceContext instanceof LambdaExpression) {
MethodBinding methodBinding = ((LambdaExpression) referenceContext).binding;
if (methodBinding != null) {
buffer.append(methodBinding.computeUniqueKey(false/*not a leaf*/));
}
}
// scope index
getScopeKey(scope, buffer);
// find number of occurences of a variable with the same name in the scope
LocalVariableBinding[] locals = scope.locals;
for (int i = 0; i < scope.localIndex; i++) { // use linear search assuming the number of locals per scope is low
LocalVariableBinding local = locals[i];
if (CharOperation.equals(this.name, local.name)) {
if (this == local)
break;
occurenceCount++;
}
}
}
// variable name
buffer.append('#');
buffer.append(this.name);
// add occurence count to avoid same key for duplicate variables
// (see https://bugs.eclipse.org/bugs/show_bug.cgi?id=149590)
if (occurenceCount > 0) {
buffer.append('#');
buffer.append(occurenceCount);
}
int length = buffer.length();
char[] uniqueKey = new char[length];
buffer.getChars(0, length, uniqueKey, 0);
return uniqueKey;
}
public AnnotationBinding[] getAnnotations() {
if (this.declaringScope == null) {
if ((this.tagBits & TagBits.AnnotationResolved) != 0) {
// annotation are already resolved
if (this.declaration == null) {
return Binding.NO_ANNOTATIONS;
}
Annotation[] annotations = this.declaration.annotations;
if (annotations != null) {
int length = annotations.length;
AnnotationBinding[] annotationBindings = new AnnotationBinding[length];
for (int i = 0; i < length; i++) {
AnnotationBinding compilerAnnotation = annotations[i].getCompilerAnnotation();
if (compilerAnnotation == null) {
return Binding.NO_ANNOTATIONS;
}
annotationBindings[i] = compilerAnnotation;
}
return annotationBindings;
}
}
return Binding.NO_ANNOTATIONS;
}
SourceTypeBinding sourceType = this.declaringScope.enclosingSourceType();
if (sourceType == null)
return Binding.NO_ANNOTATIONS;
if ((this.tagBits & TagBits.AnnotationResolved) == 0) {
if (((this.tagBits & TagBits.IsArgument) != 0) && this.declaration != null) {
Annotation[] annotationNodes = this.declaration.annotations;
if (annotationNodes != null) {
ASTNode.resolveAnnotations(this.declaringScope, annotationNodes, this, true);
}
}
}
return sourceType.retrieveAnnotations(this);
}
private void getScopeKey(BlockScope scope, StringBuffer buffer) {
int scopeIndex = scope.scopeIndex();
if (scopeIndex != -1) {
getScopeKey((BlockScope)scope.parent, buffer);
buffer.append('#');
buffer.append(scopeIndex);
}
}
// Answer whether the variable binding is a secret variable added for code gen purposes
public boolean isSecret() {
return this.declaration == null && (this.tagBits & TagBits.IsArgument) == 0;
}
public void recordInitializationEndPC(int pc) {
if (this.initializationPCs[((this.initializationCount - 1) << 1) + 1] == -1)
this.initializationPCs[((this.initializationCount - 1) << 1) + 1] = pc;
}
public void recordInitializationStartPC(int pc) {
if (this.initializationPCs == null) {
return;
}
if (this.initializationCount > 0) {
int previousEndPC = this.initializationPCs[ ((this.initializationCount - 1) << 1) + 1];
// interval still open, keep using it (108180)
if (previousEndPC == -1) {
return;
}
// optimize cases where reopening a contiguous interval
if (previousEndPC == pc) {
this.initializationPCs[ ((this.initializationCount - 1) << 1) + 1] = -1; // reuse previous interval (its range will be augmented)
return;
}
}
int index = this.initializationCount << 1;
if (index == this.initializationPCs.length) {
System.arraycopy(this.initializationPCs, 0, (this.initializationPCs = new int[this.initializationCount << 2]), 0, index);
}
this.initializationPCs[index] = pc;
this.initializationPCs[index + 1] = -1;
this.initializationCount++;
}
public void setAnnotations(AnnotationBinding[] annotations, Scope scope) {
// note: we don's use this.declaringScope because we might be called before Scope.addLocalVariable(this)
// which is where this.declaringScope is set.
if (scope == null)
return;
SourceTypeBinding sourceType = scope.enclosingSourceType();
if (sourceType != null)
sourceType.storeAnnotations(this, annotations);
}
public void resetInitializations() {
this.initializationCount = 0;
this.initializationPCs = null;
}
public String toString() {
String s = super.toString();
switch (this.useFlag){
case USED:
s += "[pos: " + String.valueOf(this.resolvedPosition) + "]"; //$NON-NLS-2$ //$NON-NLS-1$
break;
case UNUSED:
s += "[pos: unused]"; //$NON-NLS-1$
break;
case FAKE_USED:
s += "[pos: fake_used]"; //$NON-NLS-1$
break;
}
s += "[id:" + String.valueOf(this.id) + "]"; //$NON-NLS-2$ //$NON-NLS-1$
if (this.initializationCount > 0) {
s += "[pc: "; //$NON-NLS-1$
for (int i = 0; i < this.initializationCount; i++) {
if (i > 0)
s += ", "; //$NON-NLS-1$
s += String.valueOf(this.initializationPCs[i << 1]) + "-" + ((this.initializationPCs[(i << 1) + 1] == -1) ? "?" : String.valueOf(this.initializationPCs[(i<< 1) + 1])); //$NON-NLS-2$ //$NON-NLS-1$
}
s += "]"; //$NON-NLS-1$
}
return s;
}
public boolean isParameter() {
return ((this.tagBits & TagBits.IsArgument) != 0);
}
public boolean isCatchParameter() {
return false;
}
}