1 /*
2  [The "BSD license"]
3  Copyright (c) 2005-2009 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.runtime.debug;
29 
30 import org.antlr.runtime.*;
31 
32 public class DebugTokenStream implements TokenStream {
33 	protected DebugEventListener dbg;
34 	public TokenStream input;
35 	protected boolean initialStreamState = true;
36 
37 	/** Track the last mark() call result value for use in rewind(). */
38 	protected int lastMarker;
39 
DebugTokenStream(TokenStream input, DebugEventListener dbg)40 	public DebugTokenStream(TokenStream input, DebugEventListener dbg) {
41 		this.input = input;
42 		setDebugListener(dbg);
43 		// force TokenStream to get at least first valid token
44 		// so we know if there are any hidden tokens first in the stream
45 		input.LT(1);
46 	}
47 
setDebugListener(DebugEventListener dbg)48 	public void setDebugListener(DebugEventListener dbg) {
49 		this.dbg = dbg;
50 	}
51 
52 	@Override
consume()53 	public void consume() {
54 		if ( initialStreamState ) {
55 			consumeInitialHiddenTokens();
56 		}
57 		int a = input.index();
58 		Token t = input.LT(1);
59 		input.consume();
60 		int b = input.index();
61 		dbg.consumeToken(t);
62 		if ( b>a+1 ) {
63 			// then we consumed more than one token; must be off channel tokens
64 			for (int i=a+1; i<b; i++) {
65 				dbg.consumeHiddenToken(input.get(i));
66 			}
67 		}
68 	}
69 
70 	/* consume all initial off-channel tokens */
consumeInitialHiddenTokens()71 	protected void consumeInitialHiddenTokens() {
72 		int firstOnChannelTokenIndex = input.index();
73 		for (int i=0; i<firstOnChannelTokenIndex; i++) {
74 			dbg.consumeHiddenToken(input.get(i));
75 		}
76 		initialStreamState = false;
77 	}
78 
79 	@Override
LT(int i)80 	public Token LT(int i) {
81 		if ( initialStreamState ) {
82 			consumeInitialHiddenTokens();
83 		}
84 		dbg.LT(i, input.LT(i));
85 		return input.LT(i);
86 	}
87 
88 	@Override
LA(int i)89 	public int LA(int i) {
90 		if ( initialStreamState ) {
91 			consumeInitialHiddenTokens();
92 		}
93 		dbg.LT(i, input.LT(i));
94 		return input.LA(i);
95 	}
96 
97 	@Override
get(int i)98 	public Token get(int i) {
99 		return input.get(i);
100 	}
101 
102 	@Override
mark()103 	public int mark() {
104 		lastMarker = input.mark();
105 		dbg.mark(lastMarker);
106 		return lastMarker;
107 	}
108 
109 	@Override
index()110 	public int index() {
111 		return input.index();
112 	}
113 
114 	@Override
range()115 	public int range() {
116 		return input.range();
117 	}
118 
119 	@Override
rewind(int marker)120 	public void rewind(int marker) {
121 		dbg.rewind(marker);
122 		input.rewind(marker);
123 	}
124 
125 	@Override
rewind()126 	public void rewind() {
127 		dbg.rewind();
128 		input.rewind(lastMarker);
129 	}
130 
131 	@Override
release(int marker)132 	public void release(int marker) {
133 	}
134 
135 	@Override
seek(int index)136 	public void seek(int index) {
137 		// TODO: implement seek in dbg interface
138 		// db.seek(index);
139 		input.seek(index);
140 	}
141 
142 	@Override
size()143 	public int size() {
144 		return input.size();
145 	}
146 
147 	@Override
getTokenSource()148 	public TokenSource getTokenSource() {
149 		return input.getTokenSource();
150 	}
151 
152 	@Override
getSourceName()153 	public String getSourceName() {
154 		return getTokenSource().getSourceName();
155 	}
156 
157 	@Override
toString()158 	public String toString() {
159 		return input.toString();
160 	}
161 
162 	@Override
toString(int start, int stop)163 	public String toString(int start, int stop) {
164 		return input.toString(start,stop);
165 	}
166 
167 	@Override
toString(Token start, Token stop)168 	public String toString(Token start, Token stop) {
169 		return input.toString(start,stop);
170 	}
171 }
172