1 /* 2 * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package jdk.nashorn.internal.ir; 27 28 import jdk.nashorn.internal.ir.annotations.Immutable; 29 import jdk.nashorn.internal.ir.visitor.NodeVisitor; 30 31 /** 32 * IR representation for a labeled statement. It implements JoinPredecessor to hold conversions that need to be effected 33 * when the block exits normally, but is also targeted by a break statement that might bring different local variable 34 * types to the join at the break point. 35 */ 36 @Immutable 37 public final class LabelNode extends LexicalContextStatement implements JoinPredecessor { 38 private static final long serialVersionUID = 1L; 39 40 /** Label ident. */ 41 private final String labelName; 42 43 /** Statements. */ 44 private final Block body; 45 46 private final LocalVariableConversion localVariableConversion; 47 48 /** 49 * Constructor 50 * 51 * @param lineNumber line number 52 * @param token token 53 * @param finish finish 54 * @param labelName label name 55 * @param body body of label node 56 */ 57 public LabelNode(final int lineNumber, final long token, final int finish, final String labelName, final Block body) { 58 super(lineNumber, token, finish); 59 60 this.labelName = labelName; 61 this.body = body; 62 this.localVariableConversion = null; 63 } 64 65 private LabelNode(final LabelNode labelNode, final String labelName, final Block body, final LocalVariableConversion localVariableConversion) { 66 super(labelNode); 67 this.labelName = labelName; 68 this.body = body; 69 this.localVariableConversion = localVariableConversion; 70 } 71 72 @Override 73 public boolean isTerminal() { 74 return body.isTerminal(); 75 } 76 77 @Override 78 public Node accept(final LexicalContext lc, final NodeVisitor<? extends LexicalContext> visitor) { 79 if (visitor.enterLabelNode(this)) { 80 return visitor.leaveLabelNode(setBody(lc, (Block)body.accept(visitor))); 81 } 82 83 return this; 84 } 85 86 @Override 87 public void toString(final StringBuilder sb, final boolean printType) { 88 sb.append(labelName).append(':'); 89 } 90 91 /** 92 * Get the body of the node 93 * @return the body 94 */ 95 public Block getBody() { 96 return body; 97 } 98 99 /** 100 * Reset the body of the node 101 * @param lc lexical context 102 * @param body new body 103 * @return new for node if changed or existing if not 104 */ 105 public LabelNode setBody(final LexicalContext lc, final Block body) { 106 if (this.body == body) { 107 return this; 108 } 109 return Node.replaceInLexicalContext(lc, this, new LabelNode(this, labelName, body, localVariableConversion)); 110 } 111 112 /** 113 * Get the label name 114 * @return the label 115 */ 116 public String getLabelName() { 117 return labelName; 118 } 119 120 @Override 121 public LocalVariableConversion getLocalVariableConversion() { 122 return localVariableConversion; 123 } 124 125 @Override 126 public LabelNode setLocalVariableConversion(final LexicalContext lc, final LocalVariableConversion localVariableConversion) { 127 if(this.localVariableConversion == localVariableConversion) { 128 return this; 129 } 130 return Node.replaceInLexicalContext(lc, this, new LabelNode(this, labelName, body, localVariableConversion)); 131 } 132 }