Implement Huabao frame decoder

src/org/traccar/protocol/HuabaoFrameDecoder.java

@@ -0,0 +1,58 @@
+/*
+ * Copyright 2015 Anton Tananaev ([email protected])
+ *
+ * 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.buffer.ChannelBuffers;
+import org.jboss.netty.channel.Channel;
+import org.jboss.netty.channel.ChannelHandlerContext;
+import org.jboss.netty.handler.codec.frame.FrameDecoder;
+
+public class HuabaoFrameDecoder extends FrameDecoder {
+
+    @Override
+    protected Object decode(
+            ChannelHandlerContext ctx, Channel channel, ChannelBuffer buf) throws Exception {
+
+        if (buf.readableBytes() < 2) {
+            return null;
+        }
+
+        int index = buf.indexOf(buf.readerIndex() + 1, buf.writerIndex(), (byte) 0x7e);
+        if (index != -1) {
+            ChannelBuffer result = ChannelBuffers.buffer(index + 1 - buf.readerIndex());
+
+            while (buf.readerIndex() <= index) {
+                int b = buf.readUnsignedByte();
+                if (b == 0x7d) {
+                    int ext = buf.readUnsignedByte();
+                    if (ext == 0x01) {
+                        result.writeByte(0x7d);
+                    } else if (ext == 0x02) {
+                        result.writeByte(0x7e);
+                    }
+                } else {
+                    result.writeByte(b);
+                }
+            }
+
+            return result;
+        }
+
+        return null;
+    }
+
+}

test/org/traccar/protocol/HuabaoFrameDecoderTest.java

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+package org.traccar.protocol;
+
+import org.junit.Assert;
+import org.junit.Test;
+import org.traccar.ProtocolDecoderTest;
+
+public class HuabaoFrameDecoderTest extends ProtocolDecoderTest {
+
+    @Test
+    public void testDecode() throws Exception {
+
+        HuabaoFrameDecoder decoder = new HuabaoFrameDecoder();
+
+        Assert.assertEquals(
+                binary("7e307e087d557e"),
+                decoder.decode(null, null, binary("7e307d02087d01557e")));
+
+    }
+
+}