/******************************************************************************* | |
* Copyright (c) 2001 International Business Machines Corp. and others. | |
* All rights reserved. This program and the accompanying materials | |
* are made available under the terms of the Common Public License v0.5 | |
* which accompanies this distribution, and is available at | |
* http://www.eclipse.org/legal/cpl-v05.html | |
* | |
* Contributors: | |
* IBM Corporation - initial API and implementation | |
******************************************************************************/ | |
package org.eclipse.jdt.core.dom; | |
import java.util.HashMap; | |
import java.util.Map; | |
/** | |
* Assignment expression AST node type. | |
* | |
* <pre> | |
* Assignment: | |
* Expression AssignmentOperator Expression | |
* </pre> | |
* | |
* @since 2.0 | |
*/ | |
public class Assignment extends Expression { | |
/** | |
* Assignment operators (typesafe enumeration). | |
* <pre> | |
* AssignmentOperator: | |
* <b><code>=</code></b> <code>ASSIGN</code> | |
* <b><code>+=</code></b> <code>PLUS_ASSIGN</code> | |
* <b><code>-=</code></b> <code>MINUS_ASSIGN</code> | |
* <b><code>*=</code></b> <code>TIMES_ASSIGN</code> | |
* <b><code>/=</code></b> <code>DIVIDE_ASSIGN</code> | |
* <b><code>&=</code></b> <code>BIT_AND_ASSIGN</code> | |
* <b><code>|=</code></b> <code>BIT_OR_ASSIGN</code> | |
* <b><code>^=</code></b> <code>BIT_XOR_ASSIGN</code> | |
* <b><code>%=</code></b> <code>REMAINDER_ASSIGN</code> | |
* <b><code><<=</code></b> <code>LEFT_SHIFT_ASSIGN</code> | |
* <b><code>>>=</code></b> <code>RIGHT_SHIFT_SIGNED_ASSIGN</code> | |
* <b><code>>>>=</code></b> <code>RIGHT_SHIFT_UNSIGNED_ASSIGN</code> | |
* </pre> | |
*/ | |
public static class Operator { | |
/** | |
* The name of the operator | |
*/ | |
private String op; | |
/** | |
* Creates a new assignment operator with the given name. | |
* <p> | |
* Note: this constructor is private. The only instances | |
* ever created are the ones for the standard operators. | |
* </p> | |
* | |
* @param op the character sequence for the operator | |
*/ | |
private Operator(String op) { | |
this.op = op; | |
} | |
/** | |
* Returns the character sequence for the operator. | |
* | |
* @return the character sequence for the operator | |
*/ | |
public String toString() { | |
return op; | |
} | |
/** = operator. */ | |
public static final Operator ASSIGN = new Operator("=");//$NON-NLS-1$ | |
/** += operator. */ | |
public static final Operator PLUS_ASSIGN = new Operator("+=");//$NON-NLS-1$ | |
/** -= operator. */ | |
public static final Operator MINUS_ASSIGN = new Operator("-=");//$NON-NLS-1$ | |
/** *= operator. */ | |
public static final Operator TIMES_ASSIGN = new Operator("*=");//$NON-NLS-1$ | |
/** /= operator. */ | |
public static final Operator DIVIDE_ASSIGN = new Operator("/=");//$NON-NLS-1$ | |
/** &= operator. */ | |
public static final Operator BIT_AND_ASSIGN = new Operator("&=");//$NON-NLS-1$ | |
/** |= operator. */ | |
public static final Operator BIT_OR_ASSIGN = new Operator("|=");//$NON-NLS-1$ | |
/** ^= operator. */ | |
public static final Operator BIT_XOR_ASSIGN = new Operator("^=");//$NON-NLS-1$ | |
/** %= operator. */ | |
public static final Operator REMAINDER_ASSIGN = new Operator("%=");//$NON-NLS-1$ | |
/** <<== operator. */ | |
public static final Operator LEFT_SHIFT_ASSIGN = | |
new Operator("<<=");//$NON-NLS-1$ | |
/** >>== operator. */ | |
public static final Operator RIGHT_SHIFT_SIGNED_ASSIGN = | |
new Operator(">>=");//$NON-NLS-1$ | |
/** >>>== operator. */ | |
public static final Operator RIGHT_SHIFT_UNSIGNED_ASSIGN = | |
new Operator(">>>=");//$NON-NLS-1$ | |
/** | |
* Returns the assignment 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 assignment operator, or <code>null</code> if none | |
*/ | |
public static Operator toOperator(String token) { | |
return (Operator) CODES.get(token); | |
} | |
/** | |
* 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 = { | |
ASSIGN, | |
PLUS_ASSIGN, | |
MINUS_ASSIGN, | |
TIMES_ASSIGN, | |
DIVIDE_ASSIGN, | |
BIT_AND_ASSIGN, | |
BIT_OR_ASSIGN, | |
BIT_XOR_ASSIGN, | |
REMAINDER_ASSIGN, | |
LEFT_SHIFT_ASSIGN, | |
RIGHT_SHIFT_SIGNED_ASSIGN, | |
RIGHT_SHIFT_UNSIGNED_ASSIGN | |
}; | |
for (int i = 0; i < ops.length; i++) { | |
CODES.put(ops[i].toString(), ops[i]); | |
} | |
} | |
} | |
/** | |
* The assignment operator; defaults to Assignment.Operator.ASSIGN | |
*/ | |
private Assignment.Operator assignmentOperator = Assignment.Operator.ASSIGN; | |
/** | |
* The left hand side; lazily initialized; defaults to an unspecified, | |
* but legal, simple name. | |
*/ | |
private Expression leftHandSide = null; | |
/** | |
* The right hand side; lazily initialized; defaults to an unspecified, | |
* but legal, simple name. | |
*/ | |
private Expression rightHandSide = null; | |
/** | |
* Creates a new AST node for an assignment expression owned by the given | |
* AST. By default, the node has an assignment operator, and unspecified | |
* left and right hand sides. | |
* | |
* @param ast the AST that is to own this node | |
*/ | |
Assignment(AST ast) { | |
super(ast); | |
} | |
/* (omit javadoc for this method) | |
* Method declared on ASTNode. | |
*/ | |
public int getNodeType() { | |
return ASSIGNMENT; | |
} | |
/* (omit javadoc for this method) | |
* Method declared on ASTNode. | |
*/ | |
ASTNode clone(AST target) { | |
Assignment result = new Assignment(target); | |
result.setOperator(getOperator()); | |
result.setLeftHandSide((Expression) getLeftHandSide().clone(target)); | |
result.setRightHandSide((Expression) getRightHandSide().clone(target)); | |
return result; | |
} | |
/* (omit javadoc for this method) | |
* Method declared on ASTNode. | |
*/ | |
public boolean subtreeMatch(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, getLeftHandSide()); | |
acceptChild(visitor, getRightHandSide()); | |
} | |
visitor.endVisit(this); | |
} | |
/** | |
* Returns the operator of this assignment expression. | |
* | |
* @return the assignment operator | |
*/ | |
public Assignment.Operator getOperator() { | |
return assignmentOperator; | |
} | |
/** | |
* Sets the operator of this assignment expression. | |
* | |
* @param assignmentOperator the assignment operator | |
* @exception IllegalArgumentException if the argument is incorrect | |
*/ | |
public void setOperator(Assignment.Operator assignmentOperator) { | |
if (assignmentOperator == null) { | |
throw new IllegalArgumentException(); | |
} | |
modifying(); | |
this.assignmentOperator = assignmentOperator; | |
} | |
/** | |
* Returns the left hand side of this assignment expression. | |
* | |
* @return the left hand side node | |
*/ | |
public Expression getLeftHandSide() { | |
if (leftHandSide == null) { | |
// lazy initialize - use setter to ensure parent link set too | |
setLeftHandSide(new SimpleName(getAST())); | |
} | |
return leftHandSide; | |
} | |
/** | |
* Sets the left hand side of this assignment expression. | |
* | |
* @param expression the left hand side node | |
* @exception IllegalArgumentException if the node belongs to a different AST | |
* @exception IllegalArgumentException if the node already has a parent | |
* @exception IllegalArgumentException if a cycle in would be created | |
*/ | |
public void setLeftHandSide(Expression expression) { | |
if (expression == null) { | |
throw new IllegalArgumentException(); | |
} | |
// an Assignment may occur inside a Expression - must check cycles | |
replaceChild((ASTNode) this.leftHandSide, (ASTNode) expression, true); | |
this.leftHandSide = expression; | |
} | |
/** | |
* Returns the right hand side of this assignment expression. | |
* | |
* @return the right hand side node | |
*/ | |
public Expression getRightHandSide() { | |
if (rightHandSide == null) { | |
// lazy initialize - use setter to ensure parent link set too | |
setRightHandSide(new SimpleName(getAST())); | |
} | |
return rightHandSide; | |
} | |
/** | |
* Sets the right hand side of this assignment expression. | |
* | |
* @param expression the right hand side node | |
* @exception IllegalArgumentException if the node belongs to a different AST | |
* @exception IllegalArgumentException if the node already has a parent | |
* @exception IllegalArgumentException if a cycle in would be created | |
*/ | |
public void setRightHandSide(Expression expression) { | |
if (expression == null) { | |
throw new IllegalArgumentException(); | |
} | |
// an Assignment may occur inside a Expression - must check cycles | |
replaceChild((ASTNode) this.rightHandSide, (ASTNode) expression, true); | |
this.rightHandSide = expression; | |
} | |
/* (omit javadoc for this method) | |
* Method declared on ASTNode. | |
*/ | |
int memSize() { | |
// treat Code as free | |
return BASE_NODE_SIZE + 3 * 4; | |
} | |
/* (omit javadoc for this method) | |
* Method declared on ASTNode. | |
*/ | |
int treeSize() { | |
return | |
memSize() | |
+ (leftHandSide == null ? 0 : getLeftHandSide().treeSize()) | |
+ (rightHandSide == null ? 0 : getRightHandSide().treeSize()); | |
} | |
} | |