1 /* 2 [The "BSD license"] 3 Copyright (c) 2005-2009 Terence Parr 4 All rights reserved. 5 6 Redistribution and use in source and binary forms, with or without 7 modification, are permitted provided that the following conditions 8 are met: 9 1. Redistributions of source code must retain the above copyright 10 notice, this list of conditions and the following disclaimer. 11 2. Redistributions in binary form must reproduce the above copyright 12 notice, this list of conditions and the following disclaimer in the 13 documentation and/or other materials provided with the distribution. 14 3. The name of the author may not be used to endorse or promote products 15 derived from this software without specific prior written permission. 16 17 THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 package org.antlr.runtime.tree; 29 30 import org.antlr.runtime.Token; 31 32 /** A tree node that is wrapper for a Token object. After 3.0 release 33 * while building tree rewrite stuff, it became clear that computing 34 * parent and child index is very difficult and cumbersome. Better to 35 * spend the space in every tree node. If you don't want these extra 36 * fields, it's easy to cut them out in your own BaseTree subclass. 37 */ 38 public class CommonTree extends BaseTree { 39 /** A single token is the payload */ 40 public Token token; 41 42 /** What token indexes bracket all tokens associated with this node 43 * and below? 44 */ 45 protected int startIndex=-1, stopIndex=-1; 46 47 /** Who is the parent node of this node; if null, implies node is root */ 48 public CommonTree parent; 49 50 /** What index is this node in the child list? Range: 0..n-1 */ 51 public int childIndex = -1; 52 53 public CommonTree() { } 54 55 public CommonTree(CommonTree node) { 56 super(node); 57 this.token = node.token; 58 this.startIndex = node.startIndex; 59 this.stopIndex = node.stopIndex; 60 } 61 62 public CommonTree(Token t) { 63 this.token = t; 64 } 65 66 public Token getToken() { 67 return token; 68 } 69 70 public Tree dupNode() { 71 return new CommonTree(this); 72 } 73 74 public boolean isNil() { 75 return token==null; 76 } 77 78 public int getType() { 79 if ( token==null ) { 80 return Token.INVALID_TOKEN_TYPE; 81 } 82 return token.getType(); 83 } 84 85 public String getText() { 86 if ( token==null ) { 87 return null; 88 } 89 return token.getText(); 90 } 91 92 public int getLine() { 93 if ( token==null || token.getLine()==0 ) { 94 if ( getChildCount()>0 ) { 95 return getChild(0).getLine(); 96 } 97 return 0; 98 } 99 return token.getLine(); 100 } 101 102 public int getCharPositionInLine() { 103 if ( token==null || token.getCharPositionInLine()==-1 ) { 104 if ( getChildCount()>0 ) { 105 return getChild(0).getCharPositionInLine(); 106 } 107 return 0; 108 } 109 return token.getCharPositionInLine(); 110 } 111 112 public int getTokenStartIndex() { 113 if ( startIndex==-1 && token!=null ) { 114 return token.getTokenIndex(); 115 } 116 return startIndex; 117 } 118 119 public void setTokenStartIndex(int index) { 120 startIndex = index; 121 } 122 123 public int getTokenStopIndex() { 124 if ( stopIndex==-1 && token!=null ) { 125 return token.getTokenIndex(); 126 } 127 return stopIndex; 128 } 129 130 public void setTokenStopIndex(int index) { 131 stopIndex = index; 132 } 133 134 /** For every node in this subtree, make sure it's start/stop token's 135 * are set. Walk depth first, visit bottom up. Only updates nodes 136 * with at least one token index < 0. 137 */ 138 public void setUnknownTokenBoundaries() { 139 if ( children==null ) { 140 if ( startIndex<0 || stopIndex<0 ) { 141 startIndex = stopIndex = token.getTokenIndex(); 142 } 143 return; 144 } 145 for (int i=0; i<children.size(); i++) { 146 ((CommonTree)children.get(i)).setUnknownTokenBoundaries(); 147 } 148 if ( startIndex>=0 && stopIndex>=0 ) return; // already set 149 if ( children.size() > 0 ) { 150 CommonTree firstChild = (CommonTree)children.get(0); 151 CommonTree lastChild = (CommonTree)children.get(children.size()-1); 152 startIndex = firstChild.getTokenStartIndex(); 153 stopIndex = lastChild.getTokenStopIndex(); 154 } 155 } 156 157 public int getChildIndex() { 158 return childIndex; 159 } 160 161 public Tree getParent() { 162 return parent; 163 } 164 165 public void setParent(Tree t) { 166 this.parent = (CommonTree)t; 167 } 168 169 public void setChildIndex(int index) { 170 this.childIndex = index; 171 } 172 173 public String toString() { 174 if ( isNil() ) { 175 return "nil"; 176 } 177 if ( getType()==Token.INVALID_TOKEN_TYPE ) { 178 return "<errornode>"; 179 } 180 if ( token==null ) { 181 return null; 182 } 183 return token.getText(); 184 } 185 } 186
