/*******************************************************************************
* Copyright (c) 2009 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
* Zend Technologies
*******************************************************************************/
package org.eclipse.php.core.ast.nodes;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import org.eclipse.php.core.PHPVersion;
import org.eclipse.php.core.ast.match.ASTMatcher;
import org.eclipse.php.core.ast.visitor.Visitor;
/**
* Represents a prefix expression
*
* <pre>
* e.g.
*
* <pre>
* --$a, --foo()
*/
public class PrefixExpression extends Expression implements IOperationNode {
// '++'
public static final int OP_INC = 0;
// '--'
public static final int OP_DEC = 1;
// '...'
public static final int OP_UNPACK = 2;
private Expression variable;
private int operator;
/**
* The structural property of this node type.
*/
public static final ChildPropertyDescriptor VARIABLE_PROPERTY = new ChildPropertyDescriptor(PrefixExpression.class,
"variable", Expression.class, MANDATORY, CYCLE_RISK); //$NON-NLS-1$
public static final SimplePropertyDescriptor OPERATOR_PROPERTY = new SimplePropertyDescriptor(
PrefixExpression.class, "operator", Integer.class, MANDATORY); //$NON-NLS-1$
/**
* A list of property descriptors (element type:
* {@link StructuralPropertyDescriptor}), or null if uninitialized.
*/
private static final List<StructuralPropertyDescriptor> PROPERTY_DESCRIPTORS;
static {
List<StructuralPropertyDescriptor> propertyList = new ArrayList<StructuralPropertyDescriptor>(2);
propertyList.add(VARIABLE_PROPERTY);
propertyList.add(OPERATOR_PROPERTY);
PROPERTY_DESCRIPTORS = Collections.unmodifiableList(propertyList);
}
public PrefixExpression(AST ast) {
super(ast);
}
public PrefixExpression(int start, int end, AST ast, Expression variable, int operator) {
super(start, end, ast);
if (variable == null) {
throw new IllegalArgumentException();
}
setVariable(variable);
setOperator(operator);
}
public void accept0(Visitor visitor) {
final boolean visit = visitor.visit(this);
if (visit) {
childrenAccept(visitor);
}
visitor.endVisit(this);
}
public void childrenAccept(Visitor visitor) {
variable.accept(visitor);
}
public void traverseTopDown(Visitor visitor) {
accept(visitor);
variable.traverseTopDown(visitor);
}
public void traverseBottomUp(Visitor visitor) {
variable.traverseBottomUp(visitor);
accept(visitor);
}
public void toString(StringBuffer buffer, String tab) {
buffer.append(tab).append("<PrefixExpression"); //$NON-NLS-1$
appendInterval(buffer);
buffer.append(" operator='").append(getOperator(operator)).append("'>\n"); //$NON-NLS-1$ //$NON-NLS-2$
variable.toString(buffer, TAB + tab);
buffer.append("\n").append(tab).append("</PrefixExpression>"); //$NON-NLS-1$ //$NON-NLS-2$
}
public static String getOperator(int operator) {
switch (operator) {
case OP_DEC:
return "--"; //$NON-NLS-1$
case OP_INC:
return "++"; //$NON-NLS-1$
case OP_UNPACK:
return "..."; //$NON-NLS-1$
default:
throw new IllegalArgumentException();
}
}
public int getType() {
return ASTNode.PREFIX_EXPRESSION;
}
/**
* Returns the operator of this prefix expression.
*
* @return the prefix operator
*/
public int getOperator() {
return this.operator;
}
/*
* (non-Javadoc)
*
* @see
* org.eclipse.php.internal.core.ast.nodes.IOperationNode#getOperationString
* ()
*/
public String getOperationString() {
return getOperator(this.getOperator());
}
/*
* (non-Javadoc)
*
* @see
* org.eclipse.php.internal.core.ast.nodes.IOperationNode#getOperationString
* (int)
*/
public String getOperationString(int op) {
return getOperator(op);
}
/**
* Sets the operator of this prefix expression.
*
* @param operator
* the prefix operator
* @exception IllegalArgumentException
* if the argument is incorrect
*/
public void setOperator(int operator) {
if (getOperator(operator) == null) {
throw new IllegalArgumentException();
}
preValueChange(OPERATOR_PROPERTY);
this.operator = operator;
postValueChange(OPERATOR_PROPERTY);
}
final int internalGetSetIntProperty(SimplePropertyDescriptor property, boolean get, int value) {
if (property == OPERATOR_PROPERTY) {
if (get) {
return getOperator();
} else {
setOperator(value);
return 0;
}
}
// allow default implementation to flag the error
return super.internalGetSetIntProperty(property, get, value);
}
/**
* Returns the variable in the prefix expression.
*
* @return the expression node
*/
public Expression getVariable() {
return variable;
}
/**
* Sets the expression of this prefix expression.
*
* @param variable
* the new 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 setVariable(Expression variable) {
if (variable == null) {
throw new IllegalArgumentException();
}
ASTNode oldChild = this.variable;
preReplaceChild(oldChild, variable, VARIABLE_PROPERTY);
this.variable = variable;
postReplaceChild(oldChild, variable, VARIABLE_PROPERTY);
}
final ASTNode internalGetSetChildProperty(ChildPropertyDescriptor property, boolean get, ASTNode child) {
if (property == VARIABLE_PROPERTY) {
if (get) {
return getVariable();
} else {
setVariable((VariableBase) child);
return null;
}
}
// allow default implementation to flag the error
return super.internalGetSetChildProperty(property, get, child);
}
/*
* Method declared on ASTNode.
*/
public boolean subtreeMatch(ASTMatcher matcher, Object other) {
// dispatch to correct overloaded match method
return matcher.match(this, other);
}
@Override
ASTNode clone0(AST target) {
final Expression variable = ASTNode.copySubtree(target, this.getVariable());
final PrefixExpression result = new PrefixExpression(this.getStart(), this.getEnd(), target, variable,
this.getOperator());
return result;
}
@Override
List<StructuralPropertyDescriptor> internalStructuralPropertiesForType(PHPVersion apiLevel) {
return PROPERTY_DESCRIPTORS;
}
}