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/*
* Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package jdk.nashorn.internal.ir;
import jdk.nashorn.internal.codegen.Label;
import jdk.nashorn.internal.ir.visitor.NodeVisitor;
import jdk.nashorn.internal.runtime.Source;
/**
* IR representation for a WHILE statement. This is the superclass of all
* loop nodes
*/
public class WhileNode extends BreakableNode {
/** Test expression. */
protected Node test;
/** For body. */
protected Block body;
/** loop continue label. */
protected Label continueLabel;
/**
* Constructor
*
* @param source the source
* @param token token
* @param finish finish
*/
public WhileNode(final Source source, final long token, final int finish) {
super(source, token, finish);
this.breakLabel = new Label("while_break");
this.continueLabel = new Label("while_continue");
}
/**
* Copy constructor
*
* @param whileNode source node
* @param cs copy state
*/
protected WhileNode(final WhileNode whileNode, final CopyState cs) {
super(whileNode);
this.test = cs.existingOrCopy(whileNode.test);
this.body = (Block)cs.existingOrCopy(whileNode.body);
this.breakLabel = new Label(whileNode.breakLabel);
this.continueLabel = new Label(whileNode.continueLabel);
}
@Override
protected Node copy(final CopyState cs) {
return new WhileNode(this, cs);
}
@Override
public boolean isLoop() {
return true;
}
/**
* Assist in IR navigation.
* @param visitor IR navigating visitor.
*/
@Override
public Node accept(final NodeVisitor visitor) {
if (visitor.enterWhileNode(this) != null) {
test = test.accept(visitor);
body = (Block)body.accept(visitor);
return visitor.leaveWhileNode(this);
}
return this;
}
@Override
public void toString(final StringBuilder sb) {
sb.append("while (");
test.toString(sb);
sb.append(')');
}
/**
* Get the loop body
* @return body
*/
public Block getBody() {
return body;
}
/**
* Reset the loop body
* @param body new body
*/
public void setBody(final Block body) {
this.body = body;
}
/**
* Set the break label (described in {@link WhileNode#getBreakLabel()} for this while node
* @param breakLabel break label
*/
public void setBreakLabel(final Label breakLabel) {
this.breakLabel = breakLabel;
}
/**
* Get the continue label for this while node, i.e. location to go to on continue
* @return continue label
*/
public Label getContinueLabel() {
return continueLabel;
}
/**
* Set the continue label (described in {@link WhileNode#getContinueLabel()} for this while node
* @param continueLabel continue label
*/
public void setContinueLabel(final Label continueLabel) {
this.continueLabel = continueLabel;
}
/**
* Get the test expression for this loop, that upon evaluation to true does another iteration
* @return test expression
*/
public Node getTest() {
return test;
}
/**
* Set the test expression for this loop
* @param test test expression, null if infinite loop
*/
public void setTest(final Node test) {
this.test = test;
}
}
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