Modify JT600 frame decoder

2 files changed, 33 insertions, 17 deletions

diff --git a/src/org/traccar/protocol/Jt600FrameDecoder.java b/src/org/traccar/protocol/Jt600FrameDecoder.java
index 8b8f4f642..22bbd5514 100644
--- a/src/org/traccar/protocol/Jt600FrameDecoder.java
+++ b/src/org/traccar/protocol/Jt600FrameDecoder.java
@@ -26,34 +26,26 @@ public class Jt600FrameDecoder extends FrameDecoder {
 
     @Override
     protected Object decode(
-            ChannelHandlerContext ctx,
-            Channel channel,
-            ChannelBuffer buf) throws Exception {
+            ChannelHandlerContext ctx, Channel channel, ChannelBuffer buf) throws Exception {
 
-        // Check minimum length
-        int available = buf.readableBytes();
-        if (available < 10) {
+        if (buf.readableBytes() < 10) {
             return null;
         }
 
-        // Message identifier
-        char first = (char) buf.getByte(buf.readerIndex());
+        char type = (char) buf.getByte(buf.readerIndex());
 
-        if (first == '$') {
-            // Check length
+        if (type == '$') {
             int length = buf.getUnsignedShort(buf.readerIndex() + 7) + 10;
-            if (length >= available) {
+            if (length >= buf.readableBytes()) {
                 return buf.readBytes(length);
             }
-        } else if (first == '(') {
-            // Find ending
-            Integer endIndex = ChannelBufferTools.find(buf, buf.readerIndex(), available, ")");
-            if (endIndex != null) {
+        } else if (type == '(') {
+            int endIndex = buf.indexOf(buf.readerIndex(), buf.writerIndex(), (byte) ')');
+            if (endIndex != -1) {
                 return buf.readBytes(endIndex + 1);
             }
         } else {
-            // Unknown message
-            throw new ParseException(null, 0);
+            throw new ParseException(null, 0); // unknown message
         }
 
         return null;
diff --git a/test/org/traccar/protocol/Jt600FrameDecoderTest.java b/test/org/traccar/protocol/Jt600FrameDecoderTest.java
new file mode 100644
index 000000000..d4b124db7
--- /dev/null
+++ b/test/org/traccar/protocol/Jt600FrameDecoderTest.java
@@ -0,0 +1,24 @@
+package org.traccar.protocol;
+
+import org.junit.Assert;
+import org.junit.Test;
+import org.traccar.ProtocolDecoderTest;
+
+public class Jt600FrameDecoderTest extends ProtocolDecoderTest {
+
+    @Test
+    public void testDecode() throws Exception {
+
+        Jt600FrameDecoder decoder = new Jt600FrameDecoder();
+
+        Assert.assertEquals(
+                binary("28333132303832303032392C5730312C30323535332E333535352C452C323433382E303939372C532C412C3137313031322C3035333333392C302C382C32302C362C33312C352C32302C323029"),
+                decoder.decode(null, null, binary("28333132303832303032392C5730312C30323535332E333535352C452C323433382E303939372C532C412C3137313031322C3035333333392C302C382C32302C362C33312C352C32302C323029")));
+
+        Assert.assertEquals(
+                binary("24312082002911001B171012053405243809970255335555000406140003EE2B91044D1F02"),
+                decoder.decode(null, null, binary("24312082002911001B171012053405243809970255335555000406140003EE2B91044D1F02")));
+
+    }
+
+}