Refactoring for server package, Changed GameServerThread to MainServerThread.

All Server classes now in single gameServer package tags: #story[1055]
2026-05-09 06:18:44 +00:00 · 2017-07-20 11:22:30 +12:00
parent b301ce5d27
commit 8f00f3a80c
9 changed files with 85 additions and 437 deletions
@@ -0,0 +1,165 @@
+package seng302.gameServer;
+
+import seng302.gameServer.GameState;
+import seng302.models.Player;
+import seng302.models.stream.PacketBufferDelegate;
+import seng302.models.stream.StreamParser;
+import seng302.models.stream.packets.StreamPacket;
+import seng302.server.messages.Message;
+
+import java.io.*;
+import java.net.Socket;
+import java.util.zip.CRC32;
+import java.util.zip.Checksum;
+
+/**
+ * A class describing a single connection to a Client for the purposes of sending and receiving on its own thread.
+ * All server threads created and owned by the server thread handler which can trigger client updates on its threads
+ * Created by wmu16 on 13/07/17.
+ */
+public class ServerToClientThread extends Thread {
+
+    private static final Integer MAX_ID_ATTEMPTS = 10;
+
+    private InputStream is;
+    private OutputStream os;
+    private Socket socket;
+
+    private  ByteArrayOutputStream crcBuffer;
+
+    private Boolean userIdentified = false;
+    private Boolean connected = true;
+    private Boolean updateClient = true;
+
+    public ServerToClientThread(Socket socket) {
+        this.socket = socket;
+        try {
+            is = socket.getInputStream();
+            os = socket.getOutputStream();
+        } catch (IOException e) {
+            System.out.println("IO error in server thread upon grabbing streams");
+        }
+//                threeWayHandshake();
+        GameState.addPlayer(new Player(socket));
+    }
+
+    public void run() {
+        int sync1;
+        int sync2;
+        // TODO: 14/07/17 wmu16 - Work out how to fix this while loop
+        while(true) {
+            //System.out.print(".");
+
+            try {
+                //Perform a write if it is time to as delegated by the MainServerThread
+                if (updateClient) {
+                    // TODO: 13/07/17 wmu16 - Write out game state - some function that would write all appropriate messages to this output stream
+//                try {
+//                    GameState.outputState(os);
+//                } catch (IOException e) {
+//                    System.out.println("IO error in server thread upon writing to output stream");
+//                }
+                    updateClient = false;
+                }
+
+                crcBuffer = new ByteArrayOutputStream();
+                sync1 = readByte();
+                sync2 = readByte();
+                //checking if it is the start of the packet
+                if(sync1 == 0x47 && sync2 == 0x83) {
+                    int type = readByte();
+                    //No. of milliseconds since Jan 1st 1970
+                    long timeStamp = Message.bytesToLong(getBytes(6));
+                    skipBytes(4);
+                    long payloadLength = Message.bytesToLong(getBytes(2));
+                    byte[] payload = getBytes((int) payloadLength);
+                    Checksum checksum = new CRC32();
+                    checksum.update(crcBuffer.toByteArray(), 0, crcBuffer.size());
+                    long computedCrc = checksum.getValue();
+                    long packetCrc = Message.bytesToLong(getBytes(4));
+                    if (computedCrc == packetCrc) {
+                        //System.out.println("RECEIVED A PACKET");
+                        StreamParser.parsePacket(new StreamPacket(type, payloadLength, timeStamp, payload));
+                        // TODO: 17/07/17 wmu16 - Fix this or maybe we dont need to go through the main server at all!?!?
+                    } else {
+                        System.err.println("Packet has been dropped");
+                    }
+                }
+            } catch (Exception e) {
+                closeSocket();
+                return;
+            }
+        }
+
+    }
+
+    public void updateClient() {
+        updateClient = true;
+    }
+
+
+    /**
+     * Tries to confirm the connection just accepted.
+     * Sends ID, expects that ID echoed for confirmation,
+     * if so, sends a confirmation packet back to that connection
+     * Creates a player instance with that ID and this thread and adds it to the GameState
+     * If not, close the socket and end the threads execution
+     */
+    private void threeWayHandshake() {
+//        // TODO: 13/07/17 Finish using AC35
+//        Integer playerID = GameState.getUniquePlayerID();
+//        Integer confirmationID = null;
+//        Integer identificationAttempt = 0
+//        while (!userIdentified) {
+//            os.write(playerID);                                       //Send out new ID looking for echo
+//            confirmationID = is.read();
+//            if (playerID == idConfirmation) {                         //ID is echoed back. Connection is a client
+//                os.write(  some determined confirmation message  );   //Confirm to client
+//                GameState.addPlayer(new Player(playerID, this));      //Create a player in game state for client
+//                userIdentified = true;
+//            } else if (identificationAttempt > MAX_ID_ATTEMPTS) {     //No response. not a client. tidy up and go home.
+//                closeSocket();
+//                return;
+//            }
+//        identificationAttempt++;
+//        }
+    }
+
+    public void closeSocket() {
+        try {
+            socket.close();
+        } catch (IOException e) {
+            System.out.println("IO error in server thread upon trying to close socket");
+        }
+    }
+
+
+    private int readByte() throws Exception {
+        int currentByte = -1;
+        try {
+            // @TODO @FIX ConnectionReset Exception when a client disconnects before it is garbage collected
+            currentByte = is.read();
+            crcBuffer.write(currentByte);
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+        if (currentByte == -1){
+            throw new Exception();
+        }
+        return currentByte;
+    }
+
+    private byte[] getBytes(int n) throws Exception{
+        byte[] bytes = new byte[n];
+        for (int i = 0; i < n; i++){
+            bytes[i] = (byte) readByte();
+        }
+        return bytes;
+    }
+
+    private void skipBytes(long n) throws Exception{
+        for (int i=0; i < n; i++){
+            readByte();
+        }
+    }
+}