1 //////////////////////////////////////////////////////////////////////////////
2 // dexterIM - Instant Messaging Framework
3 // Copyright (C) 2003 Christoph Walcher
4 //
5 // This program is free software; you can redistribute it and/or modify
6 // it under the terms of the GNU General Public License as published by
7 // the Free Software Foundation; either version 2 of the License, or
8 // (at your option) any later version.
9 //
10 // This program 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 General Public License for more details.
14 //
15 // You should have received a copy of the GNU General Public License
16 // along with this program; if not, write to the Free Software
17 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 //////////////////////////////////////////////////////////////////////////////
19 package net.sf.dexterim.oscar.entity;
20
21 import java.io.ByteArrayInputStream;
22 import java.io.IOException;
23
24 /***
25 * @author christoph
26 *
27 */
28 public class TLVLexer {
29 private static TLVLexer instance;
30
31 private TLVLexer() {
32
33 }
34
35 public TLVCollection lexData(byte[] data, int offset) {
36 TLVCollection returnValue = new TLVCollection();
37
38 ByteArrayInputStream in = new ByteArrayInputStream(data);
39
40 in.skip(offset);
41
42 try {
43 while (in.available() > 0) {
44 // Read type word
45 byte type[] = new byte[2];
46 in.read(type);
47
48 // Read length word
49 byte lengthBytes[] = new byte[2];
50 in.read(lengthBytes);
51
52 int length = new Word(lengthBytes).getValue();
53
54 // Based on length word read data section
55 byte dataBytes[] = new byte[length];
56
57 if (length > 0) {
58 in.read(dataBytes);
59 }
60
61 // Add tlv
62 TLV tlv = new TLV(new Word(type));
63
64 tlv.setData(new VariableByte(dataBytes));
65 returnValue.add(tlv);
66 }
67 } catch (IOException e) {
68 e.printStackTrace();
69 }
70
71 return returnValue;
72 }
73
74 public TLVCollection lexData(byte[] data) {
75 return lexData(data, 0);
76 }
77
78 public static synchronized TLVLexer getInstance() {
79 if (instance == null) {
80 instance = new TLVLexer();
81 }
82
83 return instance;
84 }
85 }