re-engineered stream receiver to make it cleaner and ready to be used with the rest of the program. #story[817]

src/main/java/seng302/models/parsers/StreamReceiver.java

@@ -3,35 +3,83 @@ package seng302.models.parsers;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
-import java.math.BigInteger;
 import java.net.Socket;
-import java.nio.ByteBuffer;
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.Comparator;
+import java.util.concurrent.PriorityBlockingQueue;
 import java.util.zip.CRC32;
 import java.util.zip.Checksum;
 
 
 public class StreamReceiver {
+    private InputStream stream;
+    private Socket host;
+    private  ByteArrayOutputStream crcBuffer;
+    public PriorityBlockingQueue<StreamPacket> packetBuffer;
 
-    private static ByteArrayOutputStream buffer;
+    public StreamReceiver(String hostAddress, int hostPort, PriorityBlockingQueue packetBuffer) {
-    private static InputStream stream = null;
+        try {
-    private static boolean reading = true;
+            host = new Socket(hostAddress, hostPort);
-    private static Collection<StreamPacket> priorityQue = new ArrayList<>();
+        } catch (IOException e) {
+            e.printStackTrace();
+            System.exit(1);
+        }
+        this.packetBuffer = packetBuffer;
+    }
+
+    public void connect(){
+        try {
+            stream = host.getInputStream();
+        } catch (IOException e) {
+            e.printStackTrace();
+            System.exit(1);
+        }
+
+        int sync1;
+        int sync2;
+        boolean moreBytes = true;
+        while(moreBytes) {
+            try {
+                crcBuffer = new ByteArrayOutputStream();
+                sync1 = readByte();
+                sync2 = readByte();
+                //checking if it is the start of the packet
+                if(sync1 == 0x47 && sync2 == 0x83) {
+                    int type = readByte();
+                    System.out.println("message type: " + type);
+                    long timeStamp = bytesToLong(getBytes(6));
+                    skipBytes(4);
+                    long payloadLength = bytesToLong(getBytes(2));
+                    //No. of milliseconds since Jan 1st 1970
+                    System.out.println("timeStamp = " + timeStamp);
+                    System.out.println("payload length: " + payloadLength);
+
+
+                    Checksum checksum = new CRC32();
+                    checksum.update(crcBuffer.toByteArray(), 0, crcBuffer.size());
+//                System.out.println(checksum.getValue());
+                    long crc = bytesToLong(getBytes(4));
+//                System.out.println(crc);
+                    if (checksum.getValue() == crc) {
+                        packetBuffer.add(new StreamPacket(type, payloadLength, timeStamp, getBytes((int) payloadLength)));
+                    } else {
+                        System.err.println("Packet has been dropped");
+                    }
+                }
+            } catch (Exception e) {
+                moreBytes = false;
+            }
 
-    private static void skipBytes(long n){
-        for (int i=0; i < n; i++){
-            readByte();
         }
     }
 
-    private static int readByte() {
+    private int readByte() {
         int currentByte = -1;
         try {
             currentByte = stream.read();
-            buffer.write(currentByte);
+            crcBuffer.write(currentByte);
             if (currentByte == -1){
-                reading = false;
             }
         } catch (IOException e) {
             e.printStackTrace();
@@ -39,95 +87,32 @@ public class StreamReceiver {
         return currentByte;
     }
 
-    private static void runTest() {
+    private byte[] getBytes(int n){
-
-        Socket host = null;
-//        String hostAddress = "livedata.americascup.com";
-        String hostAddress = "csse-s302staff.canterbury.ac.nz";
-        int hostPort = 4941;
-
-        try {
-            host = new Socket(hostAddress, hostPort);
-            stream = host.getInputStream();
-        } catch (IOException e) {
-            e.printStackTrace();
-        }
-
-        int sync1;
-        int sync2;
-        //currently "reading" will not break the program nicely (because there are multiple readBytes within the while loop)
-        while(reading) {
-            buffer = new ByteArrayOutputStream();
-            sync1 = readByte();
-//            System.out.println("sync1 = " + Integer.toBinaryString(sync1));
-            sync2 = readByte();
-            //checking if it is the start of the packet
-            if(sync1 == 0x47 && sync2 == 0x83) {
-                int type = readByte();
-//                System.out.println("message type: " + type);
-                byte[] timeStampBytes = getBytes(6);
-                skipBytes(4);
-
-//                byte[] b = new byte[2];
-//                try {
-//                    stream.read(b);
-//                } catch (IOException e){
-//                    e.printStackTrace();
-//                }
-//                System.out.println("b = " + Integer.toBinaryString(b[0]));
-//                System.out.println(timeStamp);
-                long timeStamp = 0;
-                long multiplier=1;
-                for(int i = 0;i < 6;i++) {
-                    timeStamp += timeStampBytes[i]*multiplier;
-                    multiplier *= 256;
-                }
-                long payloadLength = bytesToLong(getBytes(2));
-                //No. of milliseconds since Jan 1st 1970
-//                System.out.println("timeStamp = " + timeStamp);
-//                System.out.println("payload length: " + payloadLength);
-                priorityQue.add(new StreamPacket(type, payloadLength, timeStamp, getBytes((int)payloadLength)));
-                Checksum checksum = new CRC32();
-                checksum.update(buffer.toByteArray(), 0, buffer.size());
-//                System.out.println(checksum.getValue());
-                long crc = bytesToLong(getBytes(4));
-//                System.out.println(crc);
-            }
-        }
-
-        try {
-            if (host != null) {
-                host.close();
-            }
-        } catch (IOException e) {
-            e.printStackTrace();
-        }
-
-    }
-
-    private static byte[] getBytes(int n){
         byte[] bytes = new byte[n];
         for (int i = 0; i < n; i++){
             bytes[i] = (byte) readByte();
-//            System.out.println(Integer.toBinaryString(bytes[i]));
-//            System.out.println(bytes[i]);
         }
         return bytes;
     }
 
+
+    private void skipBytes(long n){
+        for (int i=0; i < n; i++){
+            readByte();
+        }
+    }
+
     /**
-     * takes an array of up to 4 bytes and returns a positive
+     * takes an array of up to 7 bytes and returns a positive
      * long constructed from the input bytes
      *
-     * (note it is assumed the bytes coming in need to be reversed like those from a stream)
+     * @return a positive long if there is less than 7 bytes -1 otherwise
-     *
-     * @return a positive long if there is less than 4 bytes -1 otherwise
      */
-    static long bytesToLong(byte[] bytes){
+    private long bytesToLong(byte[] bytes){
         long partialLong = 0;
         int index = 0;
         for (byte b: bytes){
-            if (index > 3){
+            if (index > 6){
                 return -1;
             }
             partialLong = partialLong | (b & 0xFFL) << (index * 8);
@@ -138,9 +123,7 @@ public class StreamReceiver {
 
 
     public static void main(String[] args) {
-
+//        StreamReceiver sr = new StreamReceiver("livedata.americascup.com", 4941, pq);
-        runTest();
+//        sr.connect();
-
     }
-
 }