Merge pull request #51 from PM2-IT21bWIN-ruiz-mach-krea/useDataObjectToSend

Use data object to send

client/src/main/java/ch/zhaw/pm2/multichat/client/ChatWindowController.java

@@ -1,7 +1,9 @@
 package ch.zhaw.pm2.multichat.client;
 
+import ch.zhaw.pm2.multichat.protocol.ConnectionHandler;
 import ch.zhaw.pm2.multichat.protocol.ConnectionHandler.State;
 import ch.zhaw.pm2.multichat.protocol.ChatProtocolException;
+import ch.zhaw.pm2.multichat.protocol.Message;
 import javafx.application.Platform;
 import javafx.beans.value.ChangeListener;
 import javafx.beans.value.ObservableValue;
@@ -239,7 +241,7 @@ public class ChatWindowController {
      * @param message String to be added as Error
      */
     public void addError(String message) {
-        messages.addMessage(new Message(Message.MessageType.ERROR, null, null, message));
+        messages.addMessage(new Message(ConnectionHandler.DATA_TYPE.DATA_TYPE_ERROR, null, null, message));
     }
 
     /**
@@ -248,7 +250,6 @@ public class ChatWindowController {
     class WindowCloseHandler implements EventHandler<WindowEvent> {
 
         /**
-         *
          * @param event the event which occurred when Windows is closed
          */
         public void handle(WindowEvent event) {

client/src/main/java/ch/zhaw/pm2/multichat/client/ClientConnectionHandler.java

@@ -2,6 +2,7 @@ package ch.zhaw.pm2.multichat.client;
 
 import ch.zhaw.pm2.multichat.protocol.ChatProtocolException;
 import ch.zhaw.pm2.multichat.protocol.ConnectionHandler;
+import ch.zhaw.pm2.multichat.protocol.Message;
 import ch.zhaw.pm2.multichat.protocol.NetworkHandler;
 import javafx.beans.property.SimpleIntegerProperty;
 import javafx.beans.property.SimpleObjectProperty;
@@ -49,8 +50,8 @@ public class ClientConnectionHandler extends ConnectionHandler implements Runnab
      * Called to initialize the ClientConnectionHandler when trying to start a connection
      *
      * @param serverAddress to connect to
-     * @param serverPort to connect to
+     * @param serverPort    to connect to
-     * @param userName to connect as
+     * @param userName      to connect as
      * @throws IOException if connection to Server not possible
      */
     public void initialize(String serverAddress, int serverPort, String userName) throws IOException {
@@ -122,7 +123,7 @@ public class ClientConnectionHandler extends ConnectionHandler implements Runnab
         try {
             System.out.println("Start receiving data...");
             while (getConnection().isAvailable()) {
-                String data = getConnection().receive();
+                Message data = getConnection().receive();
                 processData(data);
             }
             System.out.println("Stopped receiving data");
@@ -162,95 +163,77 @@ public class ClientConnectionHandler extends ConnectionHandler implements Runnab
      *
      * @param data that is received in a form of a String and then used depending on its determined cause.
      */
-    private void processData(String data) {
+    private void processData(Message data) {
-        try {
+        // dispatch operation based on type parameter
-            Scanner scanner = new Scanner(data);
+        if (data.getType() == DATA_TYPE.DATA_TYPE_CONNECT) {
-            StringBuilder sender = new StringBuilder();
+            System.err.println("Illegal connect request from server");
-            StringBuilder receiver = new StringBuilder();
+        } else if (data.getType() == DATA_TYPE.DATA_TYPE_CONFIRM) {
-            StringBuilder type = new StringBuilder();
+            caseConfirm(data);
-            StringBuilder payload = new StringBuilder();
+        } else if (data.getType() == DATA_TYPE.DATA_TYPE_DISCONNECT) {
-            super.processData(scanner, sender, receiver, type, payload);
+            caseDisconnect(data);
-
+        } else if (data.getType() == DATA_TYPE.DATA_TYPE_MESSAGE) {
-            // dispatch operation based on type parameter
+            caseMessage(data);
-            if (type.toString().equals(getDataTypeConnect())) {
+        } else if (data.getType() == DATA_TYPE.DATA_TYPE_ERROR) {
-                System.err.println("Illegal connect request from server");
+            caseError(data);
-            } else if (type.toString().equals(getDataTypeConfirm())) {
+        } else {
-                caseConfirm(sender.toString(), receiver.toString(), payload.toString());
+            System.out.println("Unknown data type received: " + data.getType());
-            } else if (type.toString().equals(getDataTypeDisconnect())) {
-                caseDisconnect(sender.toString(), receiver.toString(), payload.toString());
-            } else if (type.toString().equals(getDataTypeMessage())) {
-                caseMessage(sender.toString(), receiver.toString(), payload.toString());
-            } else if (type.toString().equals(getDataTypeError())) {
-                caseError(sender.toString(), receiver.toString(), payload.toString());
-            } else {
-                System.out.println("Unknown data type received: " + type);
-            }
-        } catch (ChatProtocolException e) {
-            System.err.println("Error while processing data: " + e.getMessage());
-            sendData(USER_NONE, userName.get(), getDataTypeError(), e.getMessage());
         }
     }
 
-    private void caseConfirm(String sender, String receiver, String payload) {
+    private void caseConfirm(Message data) {
         if (state.get() == CONFIRM_CONNECT) {
-            this.userName.set(receiver);
+            this.userName.set(data.getReceiver());
             this.serverPort.set(getConnection().getRemotePort());
             this.serverAddress.set(getConnection().getRemoteHost());
-            messages.addMessage(new Message(Message.MessageType.INFO, sender, receiver, payload));
+            messages.addMessage(data);
-            System.out.println("CONFIRM: " + payload);
+            System.out.println("CONFIRM: " + data.getText());
             this.setState(CONNECTED);
         } else if (state.get() == CONFIRM_DISCONNECT) {
-            messages.addMessage(new Message(Message.MessageType.INFO, sender, receiver, payload));
+            messages.addMessage(data);
-            System.out.println("CONFIRM: " + payload);
+            System.out.println("CONFIRM: " + data.getText());
             this.setState(DISCONNECTED);
         } else {
-            System.err.println("Got unexpected confirm message: " + payload);
+            System.err.println("Got unexpected confirm message: " + data.getText());
         }
     }
 
     /**
      * Initiates the disconnect sequence and sends the message with all its info.
      *
-     * @param sender   the sender name of the message
+     * @param data Data which has been transmitted
-     * @param receiver the receiver name of the message
-     * @param payload  the added payload that corresponds to the message
      */
-    private void caseDisconnect(String sender, String receiver, String payload) {
+    private void caseDisconnect(Message data) {
         if (state.get() == DISCONNECTED) {
-            System.out.println("DISCONNECT: Already in disconnected: " + payload);
+            System.out.println("DISCONNECT: Already in disconnected: " + data.getText());
             return;
         }
-        messages.addMessage(new Message(Message.MessageType.INFO, sender, receiver, payload));
+        messages.addMessage(data);
-        System.out.println("DISCONNECT: " + payload);
+        System.out.println("DISCONNECT: " + data.getText());
         this.setState(DISCONNECTED);
     }
 
     /**
      * Initiates the procedure to send a new message and sends one as such.
      *
-     * @param sender   the sender name of the message
+     * @param data Data which has been transmitted
-     * @param receiver the receiver name of the message
-     * @param payload  the added payload that corresponds to the message
      */
-    private void caseMessage(String sender, String receiver, String payload) {
+    private void caseMessage(Message data) {
         if (state.get() != CONNECTED) {
-            System.out.println("MESSAGE: Illegal state " + state + " for message: " + payload);
+            System.out.println("MESSAGE: Illegal state " + state + " for message: " + data.getText());
             return;
         }
-        messages.addMessage(new Message(Message.MessageType.MESSAGE, sender, receiver, payload));
+        messages.addMessage(data);
-        System.out.println("MESSAGE: From " + sender + " to " + receiver + ": " + payload);
+        System.out.println("MESSAGE: From " + data.getSender() + " to " + data.getReceiver() + ": " + data.getText());
     }
 
     /**
      * Stores the message as an error message and displays it as such as well.
      *
-     * @param sender   the sender name of the message
+     * @param data Data which has been transmitted
-     * @param receiver the receiver name of the message
-     * @param payload  the added payload that corresponds to the message
      */
-    private void caseError(String sender, String receiver, String payload) {
+    private void caseError(Message data) {
-        messages.addMessage(new Message(Message.MessageType.ERROR, sender, receiver, payload));
+        messages.addMessage(data);
-        System.out.println("ERROR: " + payload);
+        System.out.println("ERROR: " + data.getText());
     }
 
     /**

client/src/main/java/ch/zhaw/pm2/multichat/client/ClientMessageList.java

@@ -1,5 +1,7 @@
 package ch.zhaw.pm2.multichat.client;
 
+import ch.zhaw.pm2.multichat.protocol.ConnectionHandler;
+import ch.zhaw.pm2.multichat.protocol.Message;
 import javafx.beans.property.SimpleBooleanProperty;
 
 import java.util.ArrayList;
@@ -15,6 +17,7 @@ public class ClientMessageList {
 
     /**
      * Adds a new message to ArrayList and also informs Listener.
+     *
      * @param message that should be added
      */
     public void addMessage(Message message) {
@@ -35,12 +38,10 @@ public class ClientMessageList {
         for (Message message : messages) {
             if (showAll || message.matchesFilter(filter)) {
                 switch (message.getType()) {
-                    case MESSAGE ->
+                    case DATA_TYPE_MESSAGE -> result.append(String.format("[%s -> %s] %s\n", message.getSender(), message.getReceiver(), message.getText()));
-                            result.append(String.format("[%s -> %s] %s\n", message.getSender(), message.getReceiver(), message.getText()));
+                    case DATA_TYPE_ERROR -> result.append(String.format("[ERROR] %s\n", message.getText()));
-                    case ERROR -> result.append(String.format("[ERROR] %s\n", message.getText()));
+                    case DATA_TYPE_CONFIRM, DATA_TYPE_DISCONNECT, DATA_TYPE_CONNECT -> result.append(String.format("[INFO] %s\n", message.getText()));
-                    case INFO -> result.append(String.format("[INFO] %s\n", message.getText()));
+                    default -> result.append(String.format("[ERROR] %s\n", "Unexpected message type: " + message.getType()));
-                    default ->
-                            result.append(String.format("[ERROR] %s\n", "Unexpected message type: " + message.getType()));
                 }
             }
         }

protocol/src/main/java/ch/zhaw/pm2/multichat/protocol/ConnectionHandler.java

@@ -3,23 +3,15 @@ package ch.zhaw.pm2.multichat.protocol;
 import java.io.EOFException;
 import java.io.IOException;
 import java.net.SocketException;
-import java.util.Scanner;
 
 /**
  * This abstract class is the superclass for ClientConnectionHandler and ServerConnectionHandler
- * It offers the DATA_TYPE Strings and a {@link State} enum for all valid connection states.
+ * It offers the DATA_TYPE for message and a {@link State} enum for all valid connection states.
- * Shared methods are implemented in this class as well {@link ConnectionHandler#sendData(String, String, String, String)} {@link ConnectionHandler#processData(Scanner, StringBuilder, StringBuilder, StringBuilder, StringBuilder)}
+ * Shared methods are implemented in this class as well {@link ConnectionHandler#sendData(String, String, DATA_TYPE, String)}
  */
 public abstract class ConnectionHandler {
     private NetworkHandler.NetworkConnection<String> connection;
 
-    // Data types used for the Chat Protocol
-    private static final String DATA_TYPE_CONNECT = "CONNECT";
-    private static final String DATA_TYPE_CONFIRM = "CONFIRM";
-    private static final String DATA_TYPE_DISCONNECT = "DISCONNECT";
-    private static final String DATA_TYPE_MESSAGE = "MESSAGE";
-    private static final String DATA_TYPE_ERROR = "ERROR";
-
     public static final String USER_NONE = "";
     public static final String USER_ALL = "*";
 
@@ -28,39 +20,44 @@ public abstract class ConnectionHandler {
         NEW, CONFIRM_CONNECT, CONNECTED, CONFIRM_DISCONNECT, DISCONNECTED, ERROR;
     }
 
-    /**
+    // DATA_TYPE of the messages
-     * @return {@link ConnectionHandler#DATA_TYPE_CONNECT}
+    public enum DATA_TYPE {
-     */
+        DATA_TYPE_CONNECT, DATA_TYPE_CONFIRM, DATA_TYPE_DISCONNECT, DATA_TYPE_MESSAGE, DATA_TYPE_ERROR
-    public static String getDataTypeConnect() {
-        return DATA_TYPE_CONNECT;
     }
 
     /**
-     * @return {@link ConnectionHandler#DATA_TYPE_CONFIRM}
+     * @return {@link DATA_TYPE}
      */
-    public static String getDataTypeConfirm() {
+    public static DATA_TYPE getDataTypeConnect() {
-        return DATA_TYPE_CONFIRM;
+        return DATA_TYPE.DATA_TYPE_CONNECT;
     }
 
     /**
-     * @return {@link ConnectionHandler#DATA_TYPE_DISCONNECT}
+     * @return {@link DATA_TYPE}
      */
-    public static String getDataTypeDisconnect() {
+    public static DATA_TYPE getDataTypeConfirm() {
-        return DATA_TYPE_DISCONNECT;
+        return DATA_TYPE.DATA_TYPE_CONFIRM;
     }
 
     /**
-     * @return {@link ConnectionHandler#DATA_TYPE_MESSAGE
+     * @return {@link DATA_TYPE}
      */
-    public static String getDataTypeMessage() {
+    public static DATA_TYPE getDataTypeDisconnect() {
-        return DATA_TYPE_MESSAGE;
+        return DATA_TYPE.DATA_TYPE_DISCONNECT;
     }
 
     /**
-     * @return {@link ConnectionHandler#DATA_TYPE_ERROR}
+     * @return {@link DATA_TYPE}
      */
-    public static String getDataTypeError() {
+    public static DATA_TYPE getDataTypeMessage() {
-        return DATA_TYPE_ERROR;
+        return DATA_TYPE.DATA_TYPE_MESSAGE;
+    }
+
+    /**
+     * @return {@link DATA_TYPE}
+     */
+    public static DATA_TYPE getDataTypeError() {
+        return DATA_TYPE.DATA_TYPE_ERROR;
     }
 
     /**
@@ -79,40 +76,6 @@ public abstract class ConnectionHandler {
         this.connection = connection;
     }
 
-    /**
-     * This method reads the data when a ConnectionHandler receives it. It tries to read out the sender, receiver, type and payload.
-     * If the data does not contain the expected number of lines, it throws a {@link ChatProtocolException}
-     *
-     * @param scanner  to read data
-     * @param sender   of the data
-     * @param receiver for the data
-     * @param type     of data
-     * @param payload  the data sent
-     * @throws ChatProtocolException if the data does not contain the expected number of lines
-     */
-    protected void processData(Scanner scanner, StringBuilder sender, StringBuilder receiver, StringBuilder type, StringBuilder payload) throws ChatProtocolException {
-        // parse data content
-        if (scanner.hasNextLine()) {
-            sender.append(scanner.nextLine());
-        } else if (scanner.hasNextLine()) {
-            receiver.append(scanner.nextLine());
-        } else {
-            throw new ChatProtocolException("No Sender found");
-        }
-        if (scanner.hasNextLine()) {
-            receiver.append(scanner.nextLine());
-        } else {
-            throw new ChatProtocolException("No Reciever found");
-        }
-        if (scanner.hasNextLine()) {
-            type.append(scanner.nextLine());
-        } else {
-            throw new ChatProtocolException("No Type found");
-        }
-        if (scanner.hasNextLine()) {
-            payload.append(scanner.nextLine());
-        }
-    }
 
     /**
      * This method gets called to send data via the socket defined in the {@link NetworkHandler.NetworkConnection}
@@ -122,14 +85,10 @@ public abstract class ConnectionHandler {
      * @param type     of the data
      * @param payload  of the data
      */
-    protected void sendData(String sender, String receiver, String type, String payload) {
+    protected void sendData(String sender, String receiver, DATA_TYPE type, String payload) {
         if (connection.isAvailable()) {
-            String data = sender + "\n" +
-                    receiver + "\n" +
-                    type + "\n" +
-                    payload + "\n";
             try {
-                connection.send(data);
+                connection.send(new Message(type, sender, receiver, payload));
             } catch (SocketException e) {
                 System.err.println("Connection closed: " + e.getMessage());
             } catch (EOFException e) {

protocol/src/main/java/ch/zhaw/pm2/multichat/protocol/Message.java

@@ -1,10 +1,12 @@
-package ch.zhaw.pm2.multichat.client;
+package ch.zhaw.pm2.multichat.protocol;
+
+import java.io.Serializable;
 
 /**
  * A Message object represents one Message of a client. Can be stored in ClientMessageList.
  */
-public class Message {
+public class Message implements Serializable {
-    private final MessageType type;
+    private final ConnectionHandler.DATA_TYPE type;
     private final String sender;
     private final String receiver;
     private final String text;
@@ -17,7 +19,7 @@ public class Message {
      * @param receiver The User who should receive the message.
      * @param text     The Text of the message.
      */
-    public Message(MessageType type, String sender, String receiver, String text) {
+    public Message(ConnectionHandler.DATA_TYPE type, String sender, String receiver, String text) {
         this.type = type;
         this.sender = sender;
         this.receiver = receiver;
@@ -39,7 +41,7 @@ public class Message {
     /**
      * @return The type of the message.
      */
-    public MessageType getType() {
+    public ConnectionHandler.DATA_TYPE getType() {
         return type;
     }
 
@@ -64,10 +66,4 @@ public class Message {
         return text;
     }
 
-    /**
-     * Enumeration of Message Types.
-     */
-    public enum MessageType {
-        INFO, MESSAGE, ERROR;
-    }
 }

protocol/src/main/java/ch/zhaw/pm2/multichat/protocol/NetworkHandler.java

@@ -38,7 +38,7 @@ import java.util.Objects;
  *             on the client side, usually the result is displayed to the user). After processing is finished the
  *             process calls {@link NetworkConnection#receive()} again to wait for the next request.
  *             </li>
- *             <li>sending data: call {@link NetworkConnection#send(Serializable data)}, which sends the given data
+ *             <li>sending data: call {@link NetworkConnection#send(Message)}, which sends the given data
  *             object to the remote side. The method returns as soon the object has been transmitted.
  *             <b>Important: {@link NetworkConnection} is not thread safe</b>, therefore make sure that only one thread
  *             at a time is sending data.</li>
@@ -270,7 +270,7 @@ public class NetworkHandler {
      *         on the client side, usually the result is displayed to the user). After processing is finished the
      *         process calls {@link NetworkConnection#receive()} again to wait for the next request.
      *     </li>
-     *     <li>sending data: call {@link NetworkConnection#send(Serializable data)}, which sends the given data
+     *     <li>sending data: call {@link NetworkConnection#send(Message)}, which sends the given data
      *         object to the remote side. The method returns as soon the object has been transmitted.
      *         <b>Important: {@link NetworkConnection} is not thread safe</b>, therefore make sure that only one thread
      *         at a time is sending data.
@@ -305,7 +305,7 @@ public class NetworkHandler {
          * @param data  data object of type T to be submitted through the connection.
          * @throws IOException if an error occurs (e.g. connection interrupted while sending, ...)
          */
-        public synchronized void send(T data) throws IOException {
+        public synchronized void send(Message data) throws IOException {
             ObjectOutputStream outputStream = new ObjectOutputStream(socket.getOutputStream());
             outputStream.writeObject(data);
         }
@@ -320,9 +320,9 @@ public class NetworkHandler {
          * @throws IOException if an error occours. (e.g. terminated locally/remotely) see above.
          * @throws ClassNotFoundException if the data object received does not match any class in the local classpath
          */
-        public T receive() throws IOException, ClassNotFoundException {
+        public Message receive() throws IOException, ClassNotFoundException {
             ObjectInputStream inputStream = new ObjectInputStream(this.socket.getInputStream());
-            return (T) inputStream.readObject();
+            return (Message) inputStream.readObject();
         }
 
         /**

server/src/main/java/ch/zhaw/pm2/multichat/server/Server.java

@@ -85,7 +85,7 @@ public class Server {
     private void start() {
         System.out.println("Server started.");
         try {
-            while (true) {
+            while (networkServer.isAvailable()) {
                 NetworkHandler.NetworkConnection<String> connection = networkServer.waitForConnection();
                 ServerConnectionHandler connectionHandler = new ServerConnectionHandler(connection, connections);
                 new Thread(connectionHandler).start();

server/src/main/java/ch/zhaw/pm2/multichat/server/ServerConnectionHandler.java

@@ -5,6 +5,7 @@ import ch.zhaw.pm2.multichat.protocol.ConnectionHandler;
 
 import static ch.zhaw.pm2.multichat.protocol.ConnectionHandler.State.*;
 
+import ch.zhaw.pm2.multichat.protocol.Message;
 import ch.zhaw.pm2.multichat.protocol.NetworkHandler;
 
 import java.io.EOFException;
@@ -61,10 +62,8 @@ public class ServerConnectionHandler extends ConnectionHandler implements Runnab
     /**
      * Constructor to initialize the connection
      *
-     * @param connection   representing the socket connection between server and client
+     * @param connection representing the socket connection between server and client
-     * @param registry     map containing all active connections between server and clients
+     * @param registry   map containing all active connections between server and clients
-
-
      */
     public ServerConnectionHandler(NetworkHandler.NetworkConnection<String> connection,
                                    Map<String, ServerConnectionHandler> registry) {
@@ -84,7 +83,7 @@ public class ServerConnectionHandler extends ConnectionHandler implements Runnab
         try {
             System.out.println("Start receiving data...");
             while (getConnection().isAvailable() && !(state == ERROR)) {
-                String data = getConnection().receive();
+                Message data = getConnection().receive();
                 processData(data);
             }
             System.out.println("Stopped receiving data");
@@ -136,28 +135,21 @@ public class ServerConnectionHandler extends ConnectionHandler implements Runnab
      *
      * @param data received by the server
      */
-    private void processData(String data) {
+    private void processData(Message data) {
         try {
-            Scanner scanner = new Scanner(data);
-            StringBuilder sender = new StringBuilder();
-            StringBuilder receiver = new StringBuilder();
-            StringBuilder type = new StringBuilder();
-            StringBuilder payload = new StringBuilder();
-            super.processData(scanner, sender, receiver, type, payload);
-
             // dispatch operation based on type parameter
-            if (type.toString().equals(getDataTypeConnect())) {
+            if (data.getType() == DATA_TYPE.DATA_TYPE_CONNECT) {
-                caseConnect(sender.toString());
+                caseConnect(data);
-            } else if (type.toString().equals(getDataTypeConfirm())) {
+            } else if (data.getType() == DATA_TYPE.DATA_TYPE_CONFIRM) {
                 System.out.println("Not expecting to receive a CONFIRM request from client");
-            } else if (type.toString().equals(getDataTypeDisconnect())) {
+            } else if (data.getType() == DATA_TYPE.DATA_TYPE_DISCONNECT) {
                 caseDisconnect();
-            } else if (type.toString().equals(getDataTypeMessage())) {
+            } else if (data.getType() == DATA_TYPE.DATA_TYPE_MESSAGE) {
-                caseMessage(sender.toString(), receiver.toString(), type.toString(), payload.toString());
+                caseMessage(data);
-            } else if (type.toString().equals(getDataTypeError())) {
+            } else if (data.getType() == DATA_TYPE.DATA_TYPE_ERROR) {
-                System.err.println("Received error from client (" + sender + "): " + payload);
+                System.err.println("Received error from client (" + data.getSender() + "): " + data.getText());
             } else {
-                System.err.println("Unknown data type received: " + type);
+                System.err.println("Unknown data type received: " + data.getType());
 
             }
         } catch (ChatProtocolException e) {
@@ -167,25 +159,26 @@ public class ServerConnectionHandler extends ConnectionHandler implements Runnab
     }
 
     /**
-     * This method is called by method {@link ServerConnectionHandler#processData(String)}
+     * This method is called by method {@link ServerConnectionHandler#processData(Message)}
      * Checks if username is valid. if valid sends response to client with confirmation.
      *
-     * @param sender of the payload
+     * @param data sent
      * @throws ChatProtocolException if username not valid
      */
-    private void caseConnect(String sender) throws ChatProtocolException {
+    private void caseConnect(Message data) throws ChatProtocolException {
         if (this.state != NEW) throw new ChatProtocolException("Illegal state for connect request: " + state);
-        if (sender.isBlank()) sender = this.userName;
         //if username not valid
-        if (connectionRegistry.containsKey(sender)) {
+        if (connectionRegistry.containsKey(data.getSender())) {
             state = ERROR;
             System.out.println(String.format("Connecting failed for new Client with IP:Port <%s:%d>.\nReason: Name already taken.",
                     getConnection().getRemoteHost(),
                     getConnection().getRemotePort()));
-            throw new ChatProtocolException("User name already taken: " + sender);
+            throw new ChatProtocolException("User name already taken: " + data.getSender());
         }
         //if username valid
-        this.userName = sender;
+        if (!data.getSender().isBlank()) {
+            this.userName = data.getSender();
+        }
         connectionRegistry.put(userName, this);
         sendData(USER_NONE, userName, getDataTypeConfirm(), "Registration successful for " + userName);
         this.state = CONNECTED;
@@ -196,7 +189,7 @@ public class ServerConnectionHandler extends ConnectionHandler implements Runnab
     }
 
     /**
-     * This method is called by method {@link ServerConnectionHandler#processData(String)}
+     * This method is called by method {@link ServerConnectionHandler#processData(Message)}
      * Disconnects connection by removing connection from registry and calling method {@link ServerConnectionHandler#stopReceiving()} to terminate socket.
      *
      * @throws ChatProtocolException if state already DISCONNECTED.
@@ -213,30 +206,27 @@ public class ServerConnectionHandler extends ConnectionHandler implements Runnab
     }
 
     /**
-     * This method is called by method {@link ServerConnectionHandler#processData(String)}
+     * This method is called by method {@link ServerConnectionHandler#processData(Message)}
      * Checks if broadcast or unicast. Sends data accordingly
      *
-     * @param sender   who sent data
+     * @param data to transmit
-     * @param receiver to receive data
-     * @param type     of message
-     * @param payload  data to transmit
      * @throws ChatProtocolException if state not equal to CONNECT
      */
-    private void caseMessage(String sender, String receiver, String type, String payload) throws ChatProtocolException {
+    private void caseMessage(Message data) throws ChatProtocolException {
         if (state != CONNECTED) throw new ChatProtocolException("Illegal state for message request: " + state);
-        if (USER_ALL.equals(receiver)) {
+        if (USER_ALL.equals(data.getReceiver())) {
             for (ServerConnectionHandler handler : connectionRegistry.values()) {
-                handler.sendData(sender, receiver, type, payload);
+                handler.sendData(data.getSender(), data.getReceiver(), data.getType(), data.getText());
             }
         } else {
-            ServerConnectionHandler handler = connectionRegistry.get(receiver);
+            ServerConnectionHandler handler = connectionRegistry.get(data.getReceiver());
             if (handler != null) {
-                handler.sendData(sender, receiver, type, payload);
+                handler.sendData(data.getSender(), data.getReceiver(), data.getType(), data.getText());
-                if (!receiver.equals(sender)) {
+                if (!data.getReceiver().equals(data.getSender())) {
-                    sendData(sender, receiver, type, payload); //send message to sender if it's a direct message and sender is not receiver.
+                    sendData(data.getSender(), data.getReceiver(), data.getType(), data.getText()); //send message to sender if it's a direct message and sender is not receiver.
                 }
             } else {
-                this.sendData(USER_NONE, userName, getDataTypeError(), "Unknown User: " + receiver);
+                this.sendData(USER_NONE, userName, getDataTypeError(), "Unknown User: " + data.getReceiver());
             }
         }
     }