Add JT600 support (fix #58)

1 files changed, 57 insertions, 0 deletions

diff --git a/src/org/traccar/protocol/Jt600FrameDecoder.java b/src/org/traccar/protocol/Jt600FrameDecoder.java
new file mode 100644
index 000000000..2e2fd228b
--- /dev/null
+++ b/src/org/traccar/protocol/Jt600FrameDecoder.java
@@ -0,0 +1,57 @@
+/*
+ * Copyright 2012 Anton Tananaev (anton.tananaev@gmail.com)
+ *
+ * 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 java.text.ParseException;
+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.ChannelBufferTools;
+
+public class Jt600FrameDecoder extends FrameDecoder {
+
+    private static int MESSAGE_LENGTH = 37;
+
+    protected Object decode(
+            ChannelHandlerContext ctx,
+            Channel channel,
+            ChannelBuffer buf) throws Exception {
+
+        // Message identifier
+        char first = (char) buf.getByte(0);
+        int length = buf.readableBytes();
+        
+        if (first == '$') {
+            // Check length
+            if (length >= MESSAGE_LENGTH) {
+                return buf.readBytes(MESSAGE_LENGTH);
+            }
+        } else if (first == '(') {
+            // Find ending
+            Integer endIndex = ChannelBufferTools.find(buf, 0, length, ")");
+            if (endIndex != null) {
+                return buf.readBytes(endIndex + 1);
+            }
+        } else {
+            // Unknown message
+            throw new ParseException(null, 0);
+        }
+
+        return null;
+    }
+
+}