/*******************************************************************************
* Copyright (c) 2000, 2013 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.HashMap;
import java.util.List;
import java.util.Map;
/**
* Postfix expression AST node type.
*
* <pre>
* PostfixExpression:
* Expression PostfixOperator
* </pre>
*
* @since 2.0
* @noinstantiate This class is not intended to be instantiated by clients.
*/
@SuppressWarnings({"rawtypes", "unchecked"})
public class PostfixExpression extends Expression {
/**
* Postfix operators (typesafe enumeration).
* <pre>
* PostfixOperator:
* <b><code>++</code></b> <code>INCREMENT</code>
* <b><code>--</code></b> <code>DECREMENT</code>
* </pre>
*/
public static class Operator {
/**
* The token for the operator.
*/
private String token;
/**
* Creates a new postfix operator with the given token.
* <p>
* Note: this constructor is private. The only instances
* ever created are the ones for the standard operators.
* </p>
*
* @param token the character sequence for the operator
*/
private Operator(String token) {
this.token = token;
}
/**
* Returns the character sequence for the operator.
*
* @return the character sequence for the operator
*/
public String toString() {
return this.token;
}
/** Postfix increment "++" operator. */
public static final Operator INCREMENT = new Operator("++");//$NON-NLS-1$
/** Postfix decrement "--" operator. */
public static final Operator DECREMENT = new Operator("--");//$NON-NLS-1$
/**
* Map from token to operator (key type: <code>String</code>;
* value type: <code>Operator</code>).
*/
private static final Map CODES;
static {
CODES = new HashMap(20);
Operator[] ops = {
INCREMENT,
DECREMENT,
};
for (int i = 0; i < ops.length; i++) {
CODES.put(ops[i].toString(), ops[i]);
}
}
/**
* Returns the postfix operator corresponding to the given string,
* or <code>null</code> if none.
* <p>
* <code>toOperator</code> is the converse of <code>toString</code>:
* that is, <code>Operator.toOperator(op.toString()) == op</code> for
* all operators <code>op</code>.
* </p>
*
* @param token the character sequence for the operator
* @return the postfix operator, or <code>null</code> if none
*/
public static Operator toOperator(String token) {
return (Operator) CODES.get(token);
}
}
/**
* The "operator" structural property of this node type (type: {@link PostfixExpression.Operator}).
* @since 3.0
*/
public static final SimplePropertyDescriptor OPERATOR_PROPERTY =
new SimplePropertyDescriptor(PostfixExpression.class, "operator", PostfixExpression.Operator.class, MANDATORY); //$NON-NLS-1$
/**
* The "operand" structural property of this node type (child type: {@link Expression}).
* @since 3.0
*/
public static final ChildPropertyDescriptor OPERAND_PROPERTY =
new ChildPropertyDescriptor(PostfixExpression.class, "operand", 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 propertyList = new ArrayList(3);
createPropertyList(PostfixExpression.class, propertyList);
addProperty(OPERAND_PROPERTY, propertyList);
addProperty(OPERATOR_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 operator; defaults to an unspecified postfix operator.
*/
private PostfixExpression.Operator operator =
PostfixExpression.Operator.INCREMENT;
/**
* The operand; lazily initialized; defaults to an unspecified,
* but legal, simple name.
*/
private Expression operand = null;
/**
* Creates a new AST node for an postfix expression owned by the given
* AST. By default, the node has unspecified (but legal) operator and
* operand.
*
* @param ast the AST that is to own this node
*/
PostfixExpression(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 Object internalGetSetObjectProperty(SimplePropertyDescriptor property, boolean get, Object value) {
if (property == OPERATOR_PROPERTY) {
if (get) {
return getOperator();
} else {
setOperator((Operator) value);
return null;
}
}
// allow default implementation to flag the error
return super.internalGetSetObjectProperty(property, get, value);
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
final ASTNode internalGetSetChildProperty(ChildPropertyDescriptor property, boolean get, ASTNode child) {
if (property == OPERAND_PROPERTY) {
if (get) {
return getOperand();
} else {
setOperand((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 POSTFIX_EXPRESSION;
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
ASTNode clone0(AST target) {
PostfixExpression result = new PostfixExpression(target);
result.setSourceRange(getStartPosition(), getLength());
result.setOperator(getOperator());
result.setOperand((Expression) getOperand().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) {
acceptChild(visitor, getOperand());
}
visitor.endVisit(this);
}
/**
* Returns the operator of this postfix expression.
*
* @return the operator
*/
public PostfixExpression.Operator getOperator() {
return this.operator;
}
/**
* Sets the operator of this postfix expression.
*
* @param operator the operator
* @exception IllegalArgumentException if the argument is incorrect
*/
public void setOperator(PostfixExpression.Operator operator) {
if (operator == null) {
throw new IllegalArgumentException();
}
preValueChange(OPERATOR_PROPERTY);
this.operator = operator;
postValueChange(OPERATOR_PROPERTY);
}
/**
* Returns the operand of this postfix expression.
*
* @return the operand expression node
*/
public Expression getOperand() {
if (this.operand == null) {
// lazy init must be thread-safe for readers
synchronized (this) {
if (this.operand == null) {
preLazyInit();
this.operand= new SimpleName(this.ast);
postLazyInit(this.operand, OPERAND_PROPERTY);
}
}
}
return this.operand;
}
/**
* Sets the operand of this postfix expression.
*
* @param expression the operand 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 setOperand(Expression expression) {
if (expression == null) {
throw new IllegalArgumentException();
}
ASTNode oldChild = this.operand;
preReplaceChild(oldChild, expression, OPERAND_PROPERTY);
this.operand = expression;
postReplaceChild(oldChild, expression, OPERAND_PROPERTY);
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
int memSize() {
// treat Operator as free
return BASE_NODE_SIZE + 2 * 4;
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
int treeSize() {
return
memSize()
+ (this.operand == null ? 0 : getOperand().treeSize());
}
}