01: /*
02: [The "BSD licence"]
03: Copyright (c) 2005-2006 Terence Parr
04: All rights reserved.
05:
06: Redistribution and use in source and binary forms, with or without
07: modification, are permitted provided that the following conditions
08: are met:
09: 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.stringtemplate.StringTemplate;
31: import org.antlr.analysis.DecisionProbe;
32: import org.antlr.analysis.DFAState;
33: import org.antlr.analysis.NFAState;
34: import org.antlr.analysis.SemanticContext;
35: import antlr.Token;
36:
37: import java.util.Iterator;
38: import java.util.List;
39: import java.util.Set;
40:
41: /** Reports a potential parsing issue with a decision; the decision is
42: * nondeterministic in some way.
43: */
44: public class GrammarUnreachableAltsMessage extends Message {
45: public DecisionProbe probe;
46: public List alts;
47:
48: public GrammarUnreachableAltsMessage(DecisionProbe probe, List alts) {
49: super (ErrorManager.MSG_UNREACHABLE_ALTS);
50: this .probe = probe;
51: this .alts = alts;
52: // flip msg ID if alts are actually token refs in Tokens rule
53: if (probe.dfa.isTokensRuleDecision()) {
54: setMessageID(ErrorManager.MSG_UNREACHABLE_TOKENS);
55: }
56: }
57:
58: public String toString() {
59: GrammarAST decisionASTNode = probe.dfa.getDecisionASTNode();
60: line = decisionASTNode.getLine();
61: column = decisionASTNode.getColumn();
62: String fileName = probe.dfa.nfa.grammar.getFileName();
63: if (fileName != null) {
64: file = fileName;
65: }
66:
67: StringTemplate st = getMessageTemplate();
68:
69: if (probe.dfa.isTokensRuleDecision()) {
70: // alts are token rules, convert to the names instead of numbers
71: for (int i = 0; i < alts.size(); i++) {
72: Integer altI = (Integer) alts.get(i);
73: String tokenName = probe
74: .getTokenNameForTokensRuleAlt(altI.intValue());
75: // reset the line/col to the token definition
76: NFAState ruleStart = probe.dfa.nfa.grammar
77: .getRuleStartState(tokenName);
78: line = ruleStart.getAssociatedASTNode().getLine();
79: column = ruleStart.getAssociatedASTNode().getColumn();
80: st.setAttribute("tokens", tokenName);
81: }
82: } else {
83: // regular alt numbers, show the alts
84: st.setAttribute("alts", alts);
85: }
86:
87: return super.toString(st);
88: }
89:
90: }
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