/******************************************************************************* * 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 net.sourceforge.phpdt.core.dom; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; /** * Prefix expression AST node type. * *
* PrefixExpression: * PrefixOperator Expression ** * @since 2.0 * @noinstantiate This class is not intended to be instantiated by clients. */ public class PrefixExpression extends Expression { /** * Prefix operators (typesafe enumeration). *
* PrefixOperator: **/ public static class Operator { /** * The token for the operator. */ private String token; /** * Creates a new prefix operator with the given token. *++
INCREMENT
*--
DECREMENT
*+
PLUS
*-
MINUS
*~
COMPLEMENT
*!
NOT
*
* Note: this constructor is private. The only instances * ever created are the ones for the standard operators. *
* * @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 token; } /** Prefix increment "++" operator. */ public static final Operator INCREMENT = new Operator("++");//$NON-NLS-1$ /** Prefix decrement "--" operator. */ public static final Operator DECREMENT = new Operator("--");//$NON-NLS-1$ /** Unary plus "+" operator. */ public static final Operator PLUS = new Operator("+");//$NON-NLS-1$ /** Unary minus "-" operator. */ public static final Operator MINUS = new Operator("-");//$NON-NLS-1$ /** Bitwise complement "~" operator. */ public static final Operator COMPLEMENT = new Operator("~");//$NON-NLS-1$ /** Logical complement "!" operator. */ public static final Operator NOT = new Operator("!");//$NON-NLS-1$ /** * Map from token to operator (key type:String
;
* value type: Operator
).
*/
private static final Map CODES;
static {
CODES = new HashMap(20);
Operator[] ops = {
INCREMENT,
DECREMENT,
PLUS,
MINUS,
COMPLEMENT,
NOT,
};
for (int i = 0; i < ops.length; i++) {
CODES.put(ops[i].toString(), ops[i]);
}
}
/**
* Returns the prefix operator corresponding to the given string,
* or null
if none.
*
* toOperator
is the converse of toString
:
* that is, Operator.toOperator(op.toString()) == op
for
* all operators op
.
*
null
if none
*/
public static Operator toOperator(String token) {
return (Operator) CODES.get(token);
}
}
/**
* The "operator" structural property of this node type.
* @since 3.0
*/
public static final SimplePropertyDescriptor OPERATOR_PROPERTY =
new SimplePropertyDescriptor(PrefixExpression.class, "operator", PrefixExpression.Operator.class, MANDATORY); //$NON-NLS-1$
/**
* The "operand" structural property of this node type.
* @since 3.0
*/
public static final ChildPropertyDescriptor OPERAND_PROPERTY =
new ChildPropertyDescriptor(PrefixExpression.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(PrefixExpression.class, propertyList);
addProperty(OPERATOR_PROPERTY, propertyList);
addProperty(OPERAND_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
* AST.JLS*
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 prefix operator.
*/
private PrefixExpression.Operator operator =
PrefixExpression.Operator.PLUS;
/**
* The operand; lazily initialized; defaults to an unspecified,
* but legal, simple name.
*/
private Expression operand = null;
/**
* Creates a new AST node for an prefix 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
*/
PrefixExpression(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 PREFIX_EXPRESSION;
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
ASTNode clone0(AST target) {
PrefixExpression result = new PrefixExpression(target);
result.setSourceRange(this.getStartPosition(), this.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) {
// visit children in normal left to right reading order
acceptChild(visitor, getOperand());
}
visitor.endVisit(this);
}
/**
* Returns the operator of this prefix expression.
*
* @return the operator
*/
public PrefixExpression.Operator getOperator() {
return this.operator;
}
/**
* Sets the operator of this prefix expression.
*
* @param operator the operator
* @exception IllegalArgumentException if the argument is incorrect
*/
public void setOperator(PrefixExpression.Operator operator) {
if (operator == null) {
throw new IllegalArgumentException();
}
preValueChange(OPERATOR_PROPERTY);
this.operator = operator;
postValueChange(OPERATOR_PROPERTY);
}
/**
* Returns the operand of this prefix 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 prefix expression.
*
* @param expression the operand expression node
* @exception IllegalArgumentException if:
*