blob: b5d060eccc2309f7566850d31b3f1454d581c67e (
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
|
/*
* Copyright 2012 - 2018 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 io.netty.buffer.ByteBuf;
import io.netty.channel.Channel;
import io.netty.channel.ChannelHandlerContext;
import org.traccar.BaseFrameDecoder;
import java.text.ParseException;
public class Jt600FrameDecoder extends BaseFrameDecoder {
@Override
protected Object decode(
ChannelHandlerContext ctx, Channel channel, ByteBuf buf) throws Exception {
if (buf.readableBytes() < 10) {
return null;
}
char type = (char) buf.getByte(buf.readerIndex());
if (type == '$') {
boolean longFormat = buf.getUnsignedByte(buf.readerIndex() + 1) == 0x75;
int length = buf.getUnsignedShort(buf.readerIndex() + (longFormat ? 8 : 7)) + 10;
if (length <= buf.readableBytes()) {
return buf.readRetainedSlice(length);
}
} else if (type == '(') {
int endIndex = buf.indexOf(buf.readerIndex(), buf.writerIndex(), (byte) ')');
if (endIndex != -1) {
return buf.readRetainedSlice(endIndex + 1);
}
} else {
throw new ParseException(null, 0); // unknown message
}
return null;
}
}
|
