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.Tool;
31import org.antlr.runtime.*;
32import org.antlr.runtime.tree.ParseTree;
33
34import java.io.BufferedReader;
35import java.io.FileReader;
36import java.util.HashSet;
37import java.util.List;
38import java.util.Set;
39import java.util.StringTokenizer;
40
41/** Interpret any ANTLR grammar:
42 *
43 *  java Interp file.g tokens-to-ignore start-rule input-file
44 *
45 *  java Interp C.g 'WS COMMENT' program t.c
46 *
47 *  where the WS and COMMENT are the names of tokens you want to have
48 *  the parser ignore.
49 */
50public class Interp {
51    public static class FilteringTokenStream extends CommonTokenStream {
52        public FilteringTokenStream(TokenSource src) { super(src); }
53        Set<Integer> hide = new HashSet<Integer>();
54        protected void sync(int i) {
55            super.sync(i);
56            if ( hide.contains(get(i).getType()) ) get(i).setChannel(Token.HIDDEN_CHANNEL);
57        }
58        public void setTokenTypeChannel(int ttype, int channel) {
59            hide.add(ttype);
60        }
61    }
62
63	// pass me a java file to parse
64	public static void main(String[] args) throws Exception {
65		if ( args.length!=4 ) {
66			System.err.println("java Interp file.g tokens-to-ignore start-rule input-file");
67			return;
68		}
69		String grammarFileName = args[0];
70		String ignoreTokens = args[1];
71		String startRule = args[2];
72		String inputFileName = args[3];
73
74		// TODO: using wrong constructor now
75		Tool tool = new Tool();
76		CompositeGrammar composite = new CompositeGrammar();
77		Grammar parser = new Grammar(tool, grammarFileName, composite);
78		composite.setDelegationRoot(parser);
79		FileReader fr = new FileReader(grammarFileName);
80		BufferedReader br = new BufferedReader(fr);
81		parser.parseAndBuildAST(br);
82		br.close();
83
84		parser.composite.assignTokenTypes();
85		parser.composite.defineGrammarSymbols();
86		parser.composite.createNFAs();
87
88		List leftRecursiveRules = parser.checkAllRulesForLeftRecursion();
89		if ( leftRecursiveRules.size()>0 ) {
90			return;
91		}
92
93		if ( parser.getRule(startRule)==null ) {
94			System.out.println("undefined start rule "+startRule);
95			return;
96		}
97
98		String lexerGrammarText = parser.getLexerGrammar();
99		Grammar lexer = new Grammar(tool);
100		lexer.importTokenVocabulary(parser);
101		lexer.fileName = grammarFileName;
102		lexer.setTool(tool);
103		if ( lexerGrammarText!=null ) {
104			lexer.setGrammarContent(lexerGrammarText);
105		}
106		else {
107			System.err.println("no lexer grammar found in "+grammarFileName);
108		}
109		lexer.composite.createNFAs();
110
111		CharStream input =
112			new ANTLRFileStream(inputFileName);
113		Interpreter lexEngine = new Interpreter(lexer, input);
114		FilteringTokenStream tokens = new FilteringTokenStream(lexEngine);
115		StringTokenizer tk = new StringTokenizer(ignoreTokens, " ");
116		while ( tk.hasMoreTokens() ) {
117			String tokenName = tk.nextToken();
118			tokens.setTokenTypeChannel(lexer.getTokenType(tokenName), 99);
119		}
120
121		if ( parser.getRule(startRule)==null ) {
122			System.err.println("Rule "+startRule+" does not exist in "+grammarFileName);
123			return;
124		}
125		Interpreter parseEngine = new Interpreter(parser, tokens);
126		ParseTree t = parseEngine.parse(startRule);
127		System.out.println(t.toStringTree());
128	}
129}
130