Home | History | Annotate | Download | only in tool 
      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  */
     28 package org.antlr.tool;
     29 
     30 import org.antlr.analysis.DecisionProbe;
     31 import org.antlr.analysis.NFAState;
     32 import org.stringtemplate.v4.ST;
     33 
     34 import java.util.List;
     35 
     36 /** Reports a potential parsing issue with a decision; the decision is
     37  *  nondeterministic in some way.
     38  */
     39 public 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