XML Message Encoder and tests class added

-added XMLMessageEncoder to encode xml files into byte array
-added test class for xml encoder
-added regatta.xml to the test resources

#story[778, 782]

src/main/java/seng302/XMLMessageEncoder.java

@@ -0,0 +1,69 @@
+package seng302;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.util.Arrays;
+
+/**
+ * Encodes a XML file into a message of AC35 format
+ */
+public class XMLMessageEncoder {
+    private byte messageVersionNumber;
+    private short ackNumber;
+    private long timeStamp;
+    private byte xmlMsgSubType;
+    private short sequenceNumber;
+    private short xmlMsgLength;
+    private String xmlMessage;
+
+    public XMLMessageEncoder(byte messageVersionNumber, short ackNumber, long timeStamp, byte xmlMsgSubType, short sequenceNumber, short xmlMsgLenght, String xmlMessage) {
+        this.messageVersionNumber = messageVersionNumber;
+        this.ackNumber = ackNumber;
+        this.timeStamp = timeStamp;
+        this.xmlMsgSubType = xmlMsgSubType;
+        this.sequenceNumber = sequenceNumber;
+        this.xmlMsgLength = xmlMsgLenght;
+        this.xmlMessage = xmlMessage;
+    }
+
+    public byte[] getByteArray() {
+        byte[] messageBytes = xmlMessage.getBytes();
+        if (messageBytes.length > this.xmlMsgLength) {
+            //System.err.println("Xml message is to big");
+            return null;
+        }
+        ByteBuffer tempOutputByteBuffer = ByteBuffer.allocate(14 + messageBytes.length);
+
+        //ackNumber converted to bytes
+        byte[] ackNumberBytes = new byte[2];
+        ackNumberBytes[0] = (byte) (ackNumber & 0xff);
+        ackNumberBytes[1] = (byte) ((ackNumber >> 8) & 0xff);
+
+        //sequenceNumber converted to bytes
+        byte[] sequenceNumberBytes = new byte[2];
+        sequenceNumberBytes[0] = (byte) (sequenceNumber & 0xff);
+        sequenceNumberBytes[1] = (byte) ((sequenceNumber >> 8) & 0xff);
+
+        //xmlMsgLength converted to bytes
+        byte[] xmlMsgLengthBytes = new byte[2];
+        xmlMsgLengthBytes[0] = (byte) (xmlMsgLength & 0xff);
+        xmlMsgLengthBytes[1] = (byte) ((xmlMsgLength >> 8) & 0xff);
+
+
+        tempOutputByteBuffer.put(messageVersionNumber);
+        tempOutputByteBuffer.put(ackNumberBytes);
+        tempOutputByteBuffer.put(longToSixBytes(timeStamp));
+        tempOutputByteBuffer.put(xmlMsgSubType);
+        tempOutputByteBuffer.put(sequenceNumberBytes);
+        tempOutputByteBuffer.put(xmlMsgLengthBytes);
+        tempOutputByteBuffer.put(messageBytes);
+
+        return tempOutputByteBuffer.array();
+    }
+
+    public byte[] longToSixBytes(long x) {
+        ByteBuffer buffer = ByteBuffer.allocate(Long.BYTES);
+        buffer.putLong(x);
+        return Arrays.copyOfRange(buffer.array(), 2, 8);
+    }
+}

src/test/java/XMLMessageEncoderTest.java

@@ -0,0 +1,54 @@
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+import seng302.XMLMessageEncoder;
+
+import java.io.*;
+
+/**
+ * Created by hba56 on 19/04/17.
+ */
+public class XMLMessageEncoderTest {
+    @Test
+    public void getByteArrayTest(){
+        StringBuilder xmlString;
+        try{
+            BufferedReader br = new BufferedReader(new InputStreamReader(
+                    this.getClass().getResourceAsStream(("raceXML/Regatta.xml"))));
+            String line;
+            xmlString = new StringBuilder();
+            while((line=br.readLine())!= null){
+                xmlString.append(line.trim());
+            }
+            XMLMessageEncoder testEncoder = new  XMLMessageEncoder((byte)1, (short)1, System.currentTimeMillis(), (byte)7, (short)1, (short)xmlString.length(), xmlString.toString());
+
+            byte[] encodedXML = testEncoder.getByteArray();
+
+            //1 + 2 + 6 + 1 + 2 + 2 + 374
+            Assert.assertEquals(388, encodedXML.length);
+        }catch (IOException e){
+            System.out.println(e);
+        }
+    }
+
+    @Test
+    public void getByteArrayNullTest(){
+        StringBuilder xmlString;
+        try{
+            BufferedReader br = new BufferedReader(new InputStreamReader(
+                    this.getClass().getResourceAsStream(("raceXML/Regatta.xml"))));
+            String line;
+            xmlString = new StringBuilder();
+            while((line=br.readLine())!= null){
+                xmlString.append(line.trim());
+            }
+            XMLMessageEncoder testEncoder = new  XMLMessageEncoder((byte)1, (short)1, System.currentTimeMillis(), (byte)7, (short)1, (short)1, xmlString.toString());
+
+            byte[] encodedXML = testEncoder.getByteArray();
+
+            Assert.assertEquals(null, encodedXML);
+        }catch (IOException e){
+            System.out.println(e);
+        }
+    }
+}

src/test/resources/raceXML/Regatta.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<RegattaConfig>
+    <RegattaID>1</RegattaID>
+    <RegattaName>Seng302 Mock Test</RegattaName>
+    <CourseName>Bermuda AC35</CourseName>
+    <CentralLatitude>-32.296577</CentralLatitude>
+    <CentralLongitude>64.854304</CentralLongitude>
+    <CentralAltitude>0.00</CentralAltitude>
+    <UtcOffset>-4</UtcOffset>
+    <MagneticVariation>-14.78</MagneticVariation>
+</RegattaConfig>