/*
 * 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.ir.annotations.Immutable;
import jdk.nashorn.internal.ir.visitor.NodeVisitor;

IR representation for an IF statement.
/** * IR representation for an IF statement. */
@Immutable public final class IfNode extends Statement implements JoinPredecessor { private static final long serialVersionUID = 1L;
Test expression.
/** Test expression. */
private final Expression test;
Pass statements.
/** Pass statements. */
private final Block pass;
Fail statements.
/** Fail statements. */
private final Block fail;
Local variable conversions that need to be performed after test if it evaluates to false, and there's no else branch.
/** * Local variable conversions that need to be performed after test if it evaluates to false, and there's no else * branch. */
private final LocalVariableConversion conversion;
Constructor
Params:
  • lineNumber – line number
  • token – token
  • finish – finish
  • test – test
  • pass – block to execute when test passes
  • fail – block to execute when test fails or null
/** * Constructor * * @param lineNumber line number * @param token token * @param finish finish * @param test test * @param pass block to execute when test passes * @param fail block to execute when test fails or null */
public IfNode(final int lineNumber, final long token, final int finish, final Expression test, final Block pass, final Block fail) { super(lineNumber, token, finish); this.test = test; this.pass = pass; this.fail = fail; this.conversion = null; } private IfNode(final IfNode ifNode, final Expression test, final Block pass, final Block fail, final LocalVariableConversion conversion) { super(ifNode); this.test = test; this.pass = pass; this.fail = fail; this.conversion = conversion; } @Override public boolean isTerminal() { return pass.isTerminal() && fail != null && fail.isTerminal(); } @Override public Node accept(final NodeVisitor<? extends LexicalContext> visitor) { if (visitor.enterIfNode(this)) { return visitor.leaveIfNode( setTest((Expression)test.accept(visitor)). setPass((Block)pass.accept(visitor)). setFail(fail == null ? null : (Block)fail.accept(visitor))); } return this; } @Override public void toString(final StringBuilder sb, final boolean printTypes) { sb.append("if ("); test.toString(sb, printTypes); sb.append(')'); }
Get the else block of this IfNode
Returns:the else block, or null if none exists
/** * Get the else block of this IfNode * @return the else block, or null if none exists */
public Block getFail() { return fail; } private IfNode setFail(final Block fail) { if (this.fail == fail) { return this; } return new IfNode(this, test, pass, fail, conversion); }
Get the then block for this IfNode
Returns:the then block
/** * Get the then block for this IfNode * @return the then block */
public Block getPass() { return pass; } private IfNode setPass(final Block pass) { if (this.pass == pass) { return this; } return new IfNode(this, test, pass, fail, conversion); }
Get the test expression for this IfNode
Returns:the test expression
/** * Get the test expression for this IfNode * @return the test expression */
public Expression getTest() { return test; }
Reset the test expression for this IfNode
Params:
  • test – a new test expression
Returns:new or same IfNode
/** * Reset the test expression for this IfNode * @param test a new test expression * @return new or same IfNode */
public IfNode setTest(final Expression test) { if (this.test == test) { return this; } return new IfNode(this, test, pass, fail, conversion); } @Override public IfNode setLocalVariableConversion(final LexicalContext lc, final LocalVariableConversion conversion) { if(this.conversion == conversion) { return this; } return new IfNode(this, test, pass, fail, conversion); } @Override public LocalVariableConversion getLocalVariableConversion() { return conversion; } }