diff options
Diffstat (limited to 'src/main/java/org/traccar/protocol/H02FrameDecoder.java')
-rw-r--r-- | src/main/java/org/traccar/protocol/H02FrameDecoder.java | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/src/main/java/org/traccar/protocol/H02FrameDecoder.java b/src/main/java/org/traccar/protocol/H02FrameDecoder.java new file mode 100644 index 000000000..583ad599f --- /dev/null +++ b/src/main/java/org/traccar/protocol/H02FrameDecoder.java @@ -0,0 +1,95 @@ +/* + * Copyright 2013 - 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; + +public class H02FrameDecoder extends BaseFrameDecoder { + + private static final int MESSAGE_SHORT = 32; + private static final int MESSAGE_LONG = 45; + + private int messageLength; + + public H02FrameDecoder(int messageLength) { + this.messageLength = messageLength; + } + + @Override + protected Object decode( + ChannelHandlerContext ctx, Channel channel, ByteBuf buf) throws Exception { + + char marker = (char) buf.getByte(buf.readerIndex()); + + while (marker != '*' && marker != '$' && marker != 'X' && buf.readableBytes() > 0) { + buf.skipBytes(1); + if (buf.readableBytes() > 0) { + marker = (char) buf.getByte(buf.readerIndex()); + } + } + + switch (marker) { + case '*': + + // Return text message + int index = buf.indexOf(buf.readerIndex(), buf.writerIndex(), (byte) '#'); + if (index != -1) { + ByteBuf result = buf.readRetainedSlice(index + 1 - buf.readerIndex()); + while (buf.isReadable() + && (buf.getByte(buf.readerIndex()) == '\r' || buf.getByte(buf.readerIndex()) == '\n')) { + buf.readByte(); // skip new line + } + return result; + } + + break; + + case '$': + + if (messageLength == 0) { + if (buf.readableBytes() == MESSAGE_LONG) { + messageLength = MESSAGE_LONG; + } else { + messageLength = MESSAGE_SHORT; + } + } + + if (buf.readableBytes() >= messageLength) { + return buf.readRetainedSlice(messageLength); + } + + break; + + case 'X': + + if (buf.readableBytes() >= MESSAGE_SHORT) { + return buf.readRetainedSlice(MESSAGE_SHORT); + } + + break; + + default: + + return null; + } + + return null; + } + +} |