1/* 2 * [The "BSD license"] 3 * Copyright (c) 2010 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 */ 28package org.antlr.tool; 29 30import org.antlr.analysis.DecisionProbe; 31import org.antlr.analysis.NFAState; 32import org.stringtemplate.v4.ST; 33 34import java.util.List; 35 36/** Reports a potential parsing issue with a decision; the decision is 37 * nondeterministic in some way. 38 */ 39public class GrammarUnreachableAltsMessage extends Message { 40 public DecisionProbe probe; 41 public List alts; 42 43 public GrammarUnreachableAltsMessage(DecisionProbe probe, 44 List alts) 45 { 46 super(ErrorManager.MSG_UNREACHABLE_ALTS); 47 this.probe = probe; 48 this.alts = alts; 49 // flip msg ID if alts are actually token refs in Tokens rule 50 if ( probe.dfa.isTokensRuleDecision() ) { 51 setMessageID(ErrorManager.MSG_UNREACHABLE_TOKENS); 52 } 53 } 54 55 public String toString() { 56 GrammarAST decisionASTNode = probe.dfa.getDecisionASTNode(); 57 line = decisionASTNode.getLine(); 58 column = decisionASTNode.getCharPositionInLine(); 59 String fileName = probe.dfa.nfa.grammar.getFileName(); 60 if ( fileName!=null ) { 61 file = fileName; 62 } 63 64 ST st = getMessageTemplate(); 65 66 if ( probe.dfa.isTokensRuleDecision() ) { 67 // alts are token rules, convert to the names instead of numbers 68 for (int i = 0; i < alts.size(); i++) { 69 Integer altI = (Integer) alts.get(i); 70 String tokenName = 71 probe.getTokenNameForTokensRuleAlt(altI.intValue()); 72 // reset the line/col to the token definition 73 NFAState ruleStart = 74 probe.dfa.nfa.grammar.getRuleStartState(tokenName); 75 line = ruleStart.associatedASTNode.getLine(); 76 column = ruleStart.associatedASTNode.getCharPositionInLine(); 77 st.add("tokens", tokenName); 78 } 79 } 80 else { 81 // regular alt numbers, show the alts 82 st.add("alts", alts); 83 } 84 85 return super.toString(st); 86 } 87 88} 89