/*
* Copyright 2013 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;
import org.traccar.helper.StringFinder;
public class WondexFrameDecoder extends FrameDecoder {
private static final int KEEP_ALIVE_LENGTH = 8;
@Override
protected Object decode(
ChannelHandlerContext ctx, Channel channel, ChannelBuffer buf) throws Exception {
if (buf.readableBytes() < KEEP_ALIVE_LENGTH) {
return null;
}
if (buf.getUnsignedByte(buf.readerIndex()) == 0xD0) {
// Send response
ChannelBuffer frame = buf.readBytes(KEEP_ALIVE_LENGTH);
if (channel != null) {
channel.write(frame);
}
return frame;
} else {
int index = buf.indexOf(buf.readerIndex(), buf.writerIndex(), new StringFinder("\r\n"));
if (index != -1) {
ChannelBuffer frame = buf.readBytes(index - buf.readerIndex());
buf.skipBytes(2);
return frame;
}
}
return null;
}
}