/jEdit/tags/jedit-4-2-pre4/gnu/regexp/REToken.java

 1/*
 2 *  gnu/regexp/REToken.java
 3 *  Copyright (C) 1998-2001 Wes Biggs
 4 *
 5 *  This library is free software; you can redistribute it and/or modify
 6 *  it under the terms of the GNU Lesser General Public License as published
 7 *  by the Free Software Foundation; either version 2.1 of the License, or
 8 *  (at your option) any later version.
 9 *
10 *  This library is distributed in the hope that it will be useful,
11 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
12 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 *  GNU Lesser General Public License for more details.
14 *
15 *  You should have received a copy of the GNU Lesser General Public License
16 *  along with this program; if not, write to the Free Software
17 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18 */
19
20package gnu.regexp;
21import java.io.Serializable;
22
23abstract class REToken implements Serializable {
24
25  protected REToken next = null;
26  protected REToken uncle = null;
27  protected int subIndex;
28
29  protected REToken(int subIndex) {
30      this.subIndex = subIndex;
31  }
32
33  int getMinimumLength() {
34    return 0;
35  }
36
37  void setUncle(REToken anUncle) {
38    uncle = anUncle;
39  }
40
41    /** Returns true if the match succeeded, false if it failed. */
42    abstract boolean match(CharIndexed input, REMatch mymatch);
43  
44    /** Returns true if the rest of the tokens match, false if they fail. */
45    protected boolean next(CharIndexed input, REMatch mymatch) {
46	if (next == null) {
47	    if (uncle == null) {
48		return true;
49	    } else {
50		return uncle.match(input, mymatch);
51	    }
52	} else {
53	    return next.match(input, mymatch);
54	}
55    }
56  
57  boolean chain(REToken token) {
58      next = token;
59      return true; // Token was accepted
60  }
61
62    abstract void dump(StringBuffer os);
63
64  void dumpAll(StringBuffer os) {
65    dump(os);
66    if (next != null) next.dumpAll(os);
67  }
68}