/*******************************************************************************
* Copyright (c) 2000, 2008 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.core.dom;
import java.util.ArrayList;
import java.util.List;
/**
* Array access expression AST node type.
*
* <pre>
* ArrayAccess:
* Expression <b>[</b> Expression <b>]</b>
* </pre>
*
* @since 2.0
* @noinstantiate This class is not intended to be instantiated by clients.
*/
public class ArrayAccess extends Expression {
/**
* The "array" structural property of this node type.
* @since 3.0
*/
public static final ChildPropertyDescriptor ARRAY_PROPERTY =
new ChildPropertyDescriptor(ArrayAccess.class, "array", Expression.class, MANDATORY, CYCLE_RISK); //$NON-NLS-1$
/**
* The "index" structural property of this node type.
* @since 3.0
*/
public static final ChildPropertyDescriptor INDEX_PROPERTY =
new ChildPropertyDescriptor(ArrayAccess.class, "index", Expression.class, MANDATORY, CYCLE_RISK); //$NON-NLS-1$
/**
* A list of property descriptors (element type:
* {@link StructuralPropertyDescriptor}),
* or null if uninitialized.
*/
private static final List PROPERTY_DESCRIPTORS;
static {
List properyList = new ArrayList(3);
createPropertyList(ArrayAccess.class, properyList);
addProperty(ARRAY_PROPERTY, properyList);
addProperty(INDEX_PROPERTY, properyList);
PROPERTY_DESCRIPTORS = reapPropertyList(properyList);
}
/**
* Returns a list of structural property descriptors for this node type.
* Clients must not modify the result.
*
* @param apiLevel the API level; one of the
* <code>AST.JLS*</code> constants
* @return a list of property descriptors (element type:
* {@link StructuralPropertyDescriptor})
* @since 3.0
*/
public static List propertyDescriptors(int apiLevel) {
return PROPERTY_DESCRIPTORS;
}
/**
* The array expression; lazily initialized; defaults to an unspecified,
* but legal, expression.
*/
private Expression arrayExpression = null;
/**
* The index expression; lazily initialized; defaults to an unspecified,
* but legal, expression.
*/
private Expression indexExpression = null;
/**
* Creates a new unparented array access expression node owned by the given
* AST. By default, the array and index expresssions are unspecified,
* but legal.
* <p>
* N.B. This constructor is package-private.
* </p>
*
* @param ast the AST that is to own this node
*/
ArrayAccess(AST ast) {
super(ast);
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
final List internalStructuralPropertiesForType(int apiLevel) {
return propertyDescriptors(apiLevel);
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
final ASTNode internalGetSetChildProperty(ChildPropertyDescriptor property, boolean get, ASTNode child) {
if (property == ARRAY_PROPERTY) {
if (get) {
return getArray();
} else {
setArray((Expression) child);
return null;
}
}
if (property == INDEX_PROPERTY) {
if (get) {
return getIndex();
} else {
setIndex((Expression) child);
return null;
}
}
// allow default implementation to flag the error
return super.internalGetSetChildProperty(property, get, child);
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
final int getNodeType0() {
return ARRAY_ACCESS;
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
ASTNode clone0(AST target) {
ArrayAccess result = new ArrayAccess(target);
result.setSourceRange(getStartPosition(), getLength());
result.setArray((Expression) getArray().clone(target));
result.setIndex((Expression) getIndex().clone(target));
return result;
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
final boolean subtreeMatch0(ASTMatcher matcher, Object other) {
// dispatch to correct overloaded match method
return matcher.match(this, other);
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
void accept0(ASTVisitor visitor) {
boolean visitChildren = visitor.visit(this);
if (visitChildren) {
// visit children in normal left to right reading order
acceptChild(visitor, getArray());
acceptChild(visitor, getIndex());
}
visitor.endVisit(this);
}
/**
* Returns the array expression of this array access expression.
*
* @return the array expression node
*/
public Expression getArray() {
if (this.arrayExpression == null) {
// lazy init must be thread-safe for readers
synchronized (this) {
if (this.arrayExpression == null) {
preLazyInit();
this.arrayExpression = new SimpleName(this.ast);
postLazyInit(this.arrayExpression, ARRAY_PROPERTY);
}
}
}
return this.arrayExpression;
}
/**
* Sets the array expression of this array access expression.
*
* @param expression the array expression node
* @exception IllegalArgumentException if:
* <ul>
* <li>the node belongs to a different AST</li>
* <li>the node already has a parent</li>
* <li>a cycle in would be created</li>
* </ul>
*/
public void setArray(Expression expression) {
if (expression == null) {
throw new IllegalArgumentException();
}
// an ArrayAccess may occur inside an Expression
// must check cycles
ASTNode oldChild = this.arrayExpression;
preReplaceChild(oldChild, expression, ARRAY_PROPERTY);
this.arrayExpression = expression;
postReplaceChild(oldChild, expression, ARRAY_PROPERTY);
}
/**
* Returns the index expression of this array access expression.
*
* @return the index expression node
*/
public Expression getIndex() {
if (this.indexExpression == null) {
// lazy init must be thread-safe for readers
synchronized (this) {
if (this.indexExpression == null) {
preLazyInit();
this.indexExpression = new SimpleName(this.ast);
postLazyInit(this.indexExpression, INDEX_PROPERTY);
}
}
}
return this.indexExpression;
}
/**
* Sets the index expression of this array access expression.
*
* @param expression the index expression node
* @exception IllegalArgumentException if:
* <ul>
* <li>the node belongs to a different AST</li>
* <li>the node already has a parent</li>
* <li>a cycle in would be created</li>
* </ul>
*/
public void setIndex(Expression expression) {
if (expression == null) {
throw new IllegalArgumentException();
}
// an ArrayAccess may occur inside an Expression
// must check cycles
ASTNode oldChild = this.indexExpression;
preReplaceChild(oldChild, expression, INDEX_PROPERTY);
this.indexExpression = expression;
postReplaceChild(oldChild, expression, INDEX_PROPERTY);
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
int memSize() {
return BASE_NODE_SIZE + 2 * 4;
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
int treeSize() {
return
memSize()
+ (this.arrayExpression == null ? 0 : getArray().treeSize())
+ (this.indexExpression == null ? 0 : getIndex().treeSize());
}
}
