blob: c8a520772cc6f669fcd5ab91242d568ec544de60 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
|
/*
* Copyright 2016 Anton Tananaev (anton@traccar.org)
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.traccar.protocol;
import org.jboss.netty.buffer.ChannelBuffer;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelHandlerContext;
import org.jboss.netty.handler.codec.frame.FrameDecoder;
public class L100FrameDecoder extends FrameDecoder {
@Override
protected Object decode(
ChannelHandlerContext ctx, Channel channel, ChannelBuffer buf) throws Exception {
if (buf.readableBytes() < 10) {
return null;
}
int header = buf.getByte(buf.readerIndex());
boolean obd = header == 'L' || header == 'H';
int index;
if (obd) {
index = buf.indexOf(buf.readerIndex(), buf.writerIndex(), (byte) '*');
} else {
index = buf.indexOf(buf.readerIndex(), buf.writerIndex(), (byte) 0x02);
if (index == -1) {
index = buf.indexOf(buf.readerIndex(), buf.writerIndex(), (byte) 0x04);
if (index == -1) {
return null;
}
}
}
index += 2; // checksum
if (buf.writerIndex() >= index) {
if (!obd) {
buf.skipBytes(2); // header
}
ChannelBuffer frame = buf.readBytes(index - buf.readerIndex() - 2);
buf.skipBytes(2); // footer
return frame;
}
return null;
}
}
|
