Implement GPS056 protocol

1 files changed, 43 insertions, 0 deletions

diff --git a/src/org/traccar/protocol/Gps056FrameDecoder.java b/src/org/traccar/protocol/Gps056FrameDecoder.java
new file mode 100644
index 000000000..7adfddd07
--- /dev/null
+++ b/src/org/traccar/protocol/Gps056FrameDecoder.java
@@ -0,0 +1,43 @@
+/*
+ * Copyright 2017 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 java.nio.charset.StandardCharsets;
+
+public class Gps056FrameDecoder extends FrameDecoder {
+
+    private static final int MESSAGE_HEADER = 4;
+
+    @Override
+    protected Object decode(
+            ChannelHandlerContext ctx, Channel channel, ChannelBuffer buf) throws Exception {
+
+        if (buf.readableBytes() >= MESSAGE_HEADER) {
+            int length = Integer.parseInt(buf.toString(2, 2, StandardCharsets.US_ASCII)) + 5;
+            if (buf.readableBytes() >= length) {
+                return buf.readBytes(length);
+            }
+        }
+
+        return null;
+    }
+
+}