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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.analysis;
29 
30 import org.antlr.tool.Grammar;
31 import org.antlr.tool.NFAFactory;
32 
33 /** An NFA (collection of NFAStates) constructed from a grammar.  This
34  *  NFA is one big machine for entire grammar.  Decision points are recorded
35  *  by the Grammar object so we can, for example, convert to DFA or simulate
36  *  the NFA (interpret a decision).
37  */
38 public class NFA {
39     public static final int INVALID_ALT_NUMBER = -1;
40 
41     /** This NFA represents which grammar? */
42     public Grammar grammar;
43 
44 	/** Which factory created this NFA? */
45     protected NFAFactory factory = null;
46 
47 	public boolean complete;
48 
NFA(Grammar g)49 	public NFA(Grammar g) {
50         this.grammar = g;
51     }
52 
getNewNFAStateNumber()53 	public int getNewNFAStateNumber() {
54 		return grammar.composite.getNewNFAStateNumber();
55 	}
56 
addState(NFAState state)57 	public void addState(NFAState state) {
58 		grammar.composite.addState(state);
59     }
60 
getState(int s)61     public NFAState getState(int s) {
62 		return grammar.composite.getState(s);
63     }
64 
getFactory()65     public NFAFactory getFactory() {
66         return factory;
67     }
68 
setFactory(NFAFactory factory)69     public void setFactory(NFAFactory factory) {
70         this.factory = factory;
71     }
72 }
73 
74