/*******************************************************************************
* 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
*******************************************************************************/
package org.eclipse.jdt.core.dom;
import java.util.ArrayList;
import java.util.List;
/**
* Switch case AST node type. A switch case is a special kind of node used only
* in switch statements. It is a <code>Statement</code> in name only.
* <p>
* <pre>
* SwitchCase:
* <b>case</b> Expression <b>:</b>
* <b>default</b> <b>:</b>
* </pre>
* </p>
*
* @since 2.0
* @noinstantiate This class is not intended to be instantiated by clients.
*/
public class SwitchCase extends Statement {
/**
* The "expression" structural property of this node type (child type: {@link Expression}).
* @since 3.0
*/
public static final ChildPropertyDescriptor EXPRESSION_PROPERTY =
new ChildPropertyDescriptor(SwitchCase.class, "expression", Expression.class, OPTIONAL, 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 propertyList = new ArrayList(2);
createPropertyList(SwitchCase.class, propertyList);
addProperty(EXPRESSION_PROPERTY, propertyList);
PROPERTY_DESCRIPTORS = reapPropertyList(propertyList);
}
/**
* 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 expression; <code>null</code> for none; lazily initialized (but
* does <b>not</b> default to none).
* @see #expressionInitialized
*/
private Expression optionalExpression = null;
/**
* Indicates whether <code>optionalExpression</code> has been initialized.
*/
private boolean expressionInitialized = false;
/**
* Creates a new AST node for a switch case pseudo-statement owned by the
* given AST. By default, there is an unspecified, but legal, expression.
*
* @param ast the AST that is to own this node
*/
SwitchCase(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 == EXPRESSION_PROPERTY) {
if (get) {
return getExpression();
} else {
setExpression((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 SWITCH_CASE;
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
ASTNode clone0(AST target) {
SwitchCase result = new SwitchCase(target);
result.setSourceRange(getStartPosition(), getLength());
result.copyLeadingComment(this);
result.setExpression(
(Expression) ASTNode.copySubtree(target, getExpression()));
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) {
acceptChild(visitor, getExpression());
}
visitor.endVisit(this);
}
/**
* Returns the expression of this switch case, or
* <code>null</code> if there is none (the "default:" case).
*
* @return the expression node, or <code>null</code> if there is none
*/
public Expression getExpression() {
if (!this.expressionInitialized) {
// lazy init must be thread-safe for readers
synchronized (this) {
if (!this.expressionInitialized) {
preLazyInit();
this.optionalExpression = new SimpleName(this.ast);
this.expressionInitialized = true;
postLazyInit(this.optionalExpression, EXPRESSION_PROPERTY);
}
}
}
return this.optionalExpression;
}
/**
* Sets the expression of this switch case, or clears it (turns it into
* the "default:" case).
*
* @param expression the expression node, or <code>null</code> to
* turn it into the "default:" case
* @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 setExpression(Expression expression) {
ASTNode oldChild = this.optionalExpression;
preReplaceChild(oldChild, expression, EXPRESSION_PROPERTY);
this.optionalExpression = expression;
this.expressionInitialized = true;
postReplaceChild(oldChild, expression, EXPRESSION_PROPERTY);
}
/**
* Returns whether this switch case represents the "default:" case.
* <p>
* This convenience method is equivalent to
* <code>getExpression() == null</code>.
* </p>
*
* @return <code>true</code> if this is the default switch case, and
* <code>false</code> if this is a non-default switch case
*/
public boolean isDefault() {
return getExpression() == null;
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
int memSize() {
return super.memSize() + 2 * 4;
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
int treeSize() {
return
memSize()
+ (this.optionalExpression == null ? 0 : this.optionalExpression.treeSize());
}
}