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