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 */
28package org.antlr.runtime.debug;
29
30import org.antlr.runtime.*;
31
32import java.util.List;
33
34public class DebugTokenStream implements TokenStream {
35	protected DebugEventListener dbg;
36	public TokenStream input;
37	protected boolean initialStreamState = true;
38
39	/** Track the last mark() call result value for use in rewind(). */
40	protected int lastMarker;
41
42	public DebugTokenStream(TokenStream input, DebugEventListener dbg) {
43		this.input = input;
44		setDebugListener(dbg);
45		// force TokenStream to get at least first valid token
46		// so we know if there are any hidden tokens first in the stream
47		input.LT(1);
48	}
49
50	public void setDebugListener(DebugEventListener dbg) {
51		this.dbg = dbg;
52	}
53
54	public void consume() {
55		if ( initialStreamState ) {
56			consumeInitialHiddenTokens();
57		}
58		int a = input.index();
59		Token t = input.LT(1);
60		input.consume();
61		int b = input.index();
62		dbg.consumeToken(t);
63		if ( b>a+1 ) {
64			// then we consumed more than one token; must be off channel tokens
65			for (int i=a+1; i<b; i++) {
66				dbg.consumeHiddenToken(input.get(i));
67			}
68		}
69	}
70
71	/* consume all initial off-channel tokens */
72	protected void consumeInitialHiddenTokens() {
73		int firstOnChannelTokenIndex = input.index();
74		for (int i=0; i<firstOnChannelTokenIndex; i++) {
75			dbg.consumeHiddenToken(input.get(i));
76		}
77		initialStreamState = false;
78	}
79
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	public int LA(int i) {
89		if ( initialStreamState ) {
90			consumeInitialHiddenTokens();
91		}
92		dbg.LT(i, input.LT(i));
93		return input.LA(i);
94	}
95
96	public Token get(int i) {
97		return input.get(i);
98	}
99
100	public int mark() {
101		lastMarker = input.mark();
102		dbg.mark(lastMarker);
103		return lastMarker;
104	}
105
106	public int index() {
107		return input.index();
108	}
109
110	public int range() {
111		return input.range();
112	}
113
114	public void rewind(int marker) {
115		dbg.rewind(marker);
116		input.rewind(marker);
117	}
118
119	public void rewind() {
120		dbg.rewind();
121		input.rewind(lastMarker);
122	}
123
124	public void release(int marker) {
125	}
126
127	public void seek(int index) {
128		// TODO: implement seek in dbg interface
129		// db.seek(index);
130		input.seek(index);
131	}
132
133	public int size() {
134		return input.size();
135	}
136
137	public TokenSource getTokenSource() {
138		return input.getTokenSource();
139	}
140
141	public String getSourceName() {
142		return getTokenSource().getSourceName();
143	}
144
145	public String toString() {
146		return input.toString();
147	}
148
149	public String toString(int start, int stop) {
150		return input.toString(start,stop);
151	}
152
153	public String toString(Token start, Token stop) {
154		return input.toString(start,stop);
155	}
156}
157