Created encoder and decoder for BoatState messages (HP packets)

- Added new MessageType.BOATSTATE enum to support new message type
- Modified EncoderFactory and DecoderFactory to support new enum
- Verify that original and decoded messages match

#story[1291]

racevisionGame/src/main/java/network/MessageDecoders/BoatStateDecoder.java

@@ -0,0 +1,38 @@
+package network.MessageDecoders;
+
+import network.Exceptions.InvalidMessageException;
+import network.Messages.AC35Data;
+import network.Messages.BoatState;
+
+import java.util.Arrays;
+
+import static network.Utils.ByteConverter.bytesToInt;
+
+/**
+ * Decoder for {@link BoatState} messages
+ */
+public class BoatStateDecoder implements MessageDecoder {
+    /**
+     * Decoded BoatState message
+     */
+    private BoatState message;
+
+    @Override
+    public AC35Data decode(byte[] encodedMessage) throws InvalidMessageException {
+        byte[] sourceID = Arrays.copyOfRange(encodedMessage, 0, 4);
+        byte boatHealth = encodedMessage[4];
+
+        // Unpack bytes into BoatState
+        this.message = new BoatState(
+                bytesToInt(sourceID),
+                boatHealth
+        );
+
+        // Return BoatState
+        return this.message;
+    }
+
+    public BoatState getMessage() {
+        return message;
+    }
+}

racevisionGame/src/main/java/network/MessageDecoders/DecoderFactory.java

@@ -59,6 +59,7 @@ public class DecoderFactory {
 
             case BOATACTION: return new BoatActionDecoder();
 
+            case BOATSTATE: return new BoatStateDecoder();
 
             default: throw new InvalidMessageTypeException("Unrecognised message type: " + type);
         }

racevisionGame/src/main/java/network/MessageDecoders/MessageDecoder.java

@@ -18,6 +18,5 @@ public interface MessageDecoder {
      * @return The decoded message.
      * @throws InvalidMessageException Thrown if the encoded message is invalid in some way, or cannot be decoded.
      */
-    public AC35Data decode(byte[] encodedMessage) throws InvalidMessageException;
+     AC35Data decode(byte[] encodedMessage) throws InvalidMessageException;
-
 }

racevisionGame/src/main/java/network/MessageEncoders/BoatStateEncoder.java

@@ -0,0 +1,32 @@
+package network.MessageEncoders;
+
+import network.Exceptions.InvalidMessageException;
+import network.Messages.AC35Data;
+import network.Messages.BoatState;
+
+import java.nio.ByteBuffer;
+
+import static network.Utils.ByteConverter.intToBytes;
+
+/**
+ * Encoder for {@link BoatState} message
+ */
+public class BoatStateEncoder implements MessageEncoder {
+    @Override
+    public byte[] encode(AC35Data message) throws InvalidMessageException {
+        // Downcast message
+        BoatState boatState = (BoatState)message;
+
+        //Serialise message
+        byte[] sourceID = intToBytes(boatState.getSourceID());
+        byte boatHealth = (byte)boatState.getBoatHealth();
+
+        // Pack bytes into string
+        ByteBuffer boatStateMessage = ByteBuffer.allocate(5);
+        boatStateMessage.put(sourceID);
+        boatStateMessage.put(boatHealth);
+
+        // Return byte string
+        return boatStateMessage.array();
+    }
+}

racevisionGame/src/main/java/network/MessageEncoders/EncoderFactory.java

@@ -59,6 +59,7 @@ public class EncoderFactory {
 
             case BOATACTION: return new BoatActionEncoder();
 
+            case BOATSTATE: return new BoatStateEncoder();
 
             default: throw new InvalidMessageTypeException("Unrecognised message type: " + type);
         }

racevisionGame/src/main/java/network/Messages/BoatState.java

@@ -0,0 +1,31 @@
+package network.Messages;
+
+import network.Messages.Enums.MessageType;
+
+/**
+ * Represents the information in a BoatState message according to protocol meeting
+ */
+public class BoatState extends AC35Data {
+    /**
+     * Source ID of boat described in message
+     */
+    private int sourceID;
+    /**
+     * Health between 0-100 of boat with above source ID
+     */
+    private int boatHealth;
+
+    public BoatState(int sourceID, int boatHealth) {
+        super(MessageType.BOATSTATE);
+        this.sourceID = sourceID;
+        this.boatHealth = boatHealth;
+    }
+
+    public int getSourceID() {
+        return sourceID;
+    }
+
+    public int getBoatHealth() {
+        return boatHealth;
+    }
+}

racevisionGame/src/main/java/network/Messages/Enums/MessageType.java

@@ -43,6 +43,8 @@ public enum MessageType {
 
     HOSTED_GAMES_REQUEST(109),
 
+    BOATSTATE(103),
+
     NOTAMESSAGE(0);
 
 
@@ -56,7 +58,7 @@ public enum MessageType {
      * Creates a MessageType enum from a given primitive integer value, cast to a byte.
      * @param value Integer, which is cast to byte, to construct from.
      */
-    private MessageType(int value) {
+    MessageType(int value) {
         this.value = (byte)value;
     }
 

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

@@ -0,0 +1,33 @@
+package network.MessageDecoders;
+
+import network.Exceptions.InvalidMessageException;
+import network.MessageEncoders.RaceVisionByteEncoder;
+import network.Messages.BoatState;
+import org.junit.Before;
+import org.junit.Test;
+
+import static org.testng.Assert.*;
+
+/**
+ * Test for the {@link network.Messages.BoatState} encoder and decoder.
+ */
+public class BoatStateDecoderTest {
+    private BoatState originalMessage;
+    private BoatState decodedMessage;
+
+    @Before
+    public void setUp() throws InvalidMessageException {
+        originalMessage = new BoatState(0, 100);
+
+        byte[] encodedMessage = RaceVisionByteEncoder.encode(originalMessage);
+        BoatStateDecoder decoder = new BoatStateDecoder();
+        decoder.decode(encodedMessage);
+        decodedMessage = decoder.getMessage();
+    }
+
+    @Test
+    public void decodingEqualsOriginal() {
+        assertEquals(originalMessage.getSourceID(), decodedMessage.getSourceID());
+        assertEquals(originalMessage.getBoatHealth(), decodedMessage.getBoatHealth());
+    }
+}