Renamed Heartbeat to HeartBeat.

Added HeartBeatDecoder.
Added HeartBeatEncoder.
BinaryMessageDecoder now uses HeartBeatDecoder.
MockOutput now logs a warning if a heartBeat cannot be encoded.
Added HeartBeatDecoderTest.
issue #35 #36
#story[1095]

racevisionGame/src/test/java/network/MessageDecoders/HeartBeatDecoderTest.java

@@ -0,0 +1,74 @@
+package network.MessageDecoders;
+
+import network.Exceptions.InvalidMessageException;
+import network.MessageEncoders.RaceVisionByteEncoder;
+import network.Messages.BoatAction;
+import network.Messages.Enums.BoatActionEnum;
+import network.Messages.HeartBeat;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+
+/**
+ * Test for the HeartBeat encoder and decoder
+ */
+public class HeartBeatDecoderTest {
+
+
+    /**
+     * Encodes and decodes a given message.
+     * @param message Message to encode/decode.
+     * @return The decoded message.
+     */
+    private HeartBeat encodeDecodeMessage(HeartBeat message) throws InvalidMessageException {
+
+        //Encode.
+        byte [] testEncodedMessage = RaceVisionByteEncoder.encode(message);
+
+        //Decode.
+        HeartBeatDecoder testDecoder = new HeartBeatDecoder(testEncodedMessage);
+        HeartBeat decodedMessage = testDecoder.getMessage();
+
+        return decodedMessage;
+    }
+
+
+    /**
+     * Tests if a heartbeat message with a given sequence number can be encoded and decoded correctly.
+     * @param sequenceNumber The sequenceNumber to use.
+     */
+    private void heartBeatTest(long sequenceNumber) throws Exception {
+
+        //Prepare message.
+        HeartBeat beforeMessage = new HeartBeat(sequenceNumber);
+
+
+        //Encode/decode it.
+        HeartBeat afterMessage = encodeDecodeMessage(beforeMessage);
+
+
+        //Compare.
+        assertEquals(beforeMessage.getSequenceNumber(), afterMessage.getSequenceNumber());
+
+    }
+
+
+    /**
+     * Tests if a heartbeat message with a sequence number of zero can be encoded and decoded correctly.
+     */
+    @Test
+    public void heartBeatZeroTest() throws Exception {
+        heartBeatTest(0);
+    }
+
+    /**
+     * Tests if a heartbeat message with a sequence number of 1234512 can be encoded and decoded correctly.
+     */
+    @Test
+    public void heartBeatNonZeroTest() throws Exception {
+        heartBeatTest(1234512);
+    }
+
+
+}