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

Use data object to send
This commit is contained in:
Roman Schenk 2022-04-16 22:39:52 +02:00 committed by GitHub Enterprise
commit a603f05135
8 changed files with 121 additions and 191 deletions

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@ -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) {

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@ -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 userName to connect as
* @param serverPort to connect to
* @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) {
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())) {
System.err.println("Illegal connect request from server");
} else if (type.toString().equals(getDataTypeConfirm())) {
caseConfirm(sender.toString(), receiver.toString(), payload.toString());
} 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 processData(Message data) {
// dispatch operation based on type parameter
if (data.getType() == DATA_TYPE.DATA_TYPE_CONNECT) {
System.err.println("Illegal connect request from server");
} else if (data.getType() == DATA_TYPE.DATA_TYPE_CONFIRM) {
caseConfirm(data);
} else if (data.getType() == DATA_TYPE.DATA_TYPE_DISCONNECT) {
caseDisconnect(data);
} else if (data.getType() == DATA_TYPE.DATA_TYPE_MESSAGE) {
caseMessage(data);
} else if (data.getType() == DATA_TYPE.DATA_TYPE_ERROR) {
caseError(data);
} else {
System.out.println("Unknown data type received: " + data.getType());
}
}
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));
System.out.println("CONFIRM: " + payload);
messages.addMessage(data);
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));
System.out.println("CONFIRM: " + payload);
messages.addMessage(data);
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 receiver the receiver name of the message
* @param payload the added payload that corresponds to the message
* @param data Data which has been transmitted
*/
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));
System.out.println("DISCONNECT: " + payload);
messages.addMessage(data);
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 receiver the receiver name of the message
* @param payload the added payload that corresponds to the message
* @param data Data which has been transmitted
*/
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));
System.out.println("MESSAGE: From " + sender + " to " + receiver + ": " + payload);
messages.addMessage(data);
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 receiver the receiver name of the message
* @param payload the added payload that corresponds to the message
* @param data Data which has been transmitted
*/
private void caseError(String sender, String receiver, String payload) {
messages.addMessage(new Message(Message.MessageType.ERROR, sender, receiver, payload));
System.out.println("ERROR: " + payload);
private void caseError(Message data) {
messages.addMessage(data);
System.out.println("ERROR: " + data.getText());
}
/**

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@ -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 ->
result.append(String.format("[%s -> %s] %s\n", message.getSender(), message.getReceiver(), message.getText()));
case ERROR -> result.append(String.format("[ERROR] %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()));
case DATA_TYPE_MESSAGE -> 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 DATA_TYPE_CONFIRM, DATA_TYPE_DISCONNECT, DATA_TYPE_CONNECT -> result.append(String.format("[INFO] %s\n", message.getText()));
default -> result.append(String.format("[ERROR] %s\n", "Unexpected message type: " + message.getType()));
}
}
}

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@ -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.
* Shared methods are implemented in this class as well {@link ConnectionHandler#sendData(String, String, String, String)} {@link ConnectionHandler#processData(Scanner, StringBuilder, StringBuilder, StringBuilder, StringBuilder)}
* 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, 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;
}
/**
* @return {@link ConnectionHandler#DATA_TYPE_CONNECT}
*/
public static String getDataTypeConnect() {
return DATA_TYPE_CONNECT;
// DATA_TYPE of the messages
public enum DATA_TYPE {
DATA_TYPE_CONNECT, DATA_TYPE_CONFIRM, DATA_TYPE_DISCONNECT, DATA_TYPE_MESSAGE, DATA_TYPE_ERROR
}
/**
* @return {@link ConnectionHandler#DATA_TYPE_CONFIRM}
* @return {@link DATA_TYPE}
*/
public static String getDataTypeConfirm() {
return DATA_TYPE_CONFIRM;
public static DATA_TYPE getDataTypeConnect() {
return DATA_TYPE.DATA_TYPE_CONNECT;
}
/**
* @return {@link ConnectionHandler#DATA_TYPE_DISCONNECT}
* @return {@link DATA_TYPE}
*/
public static String getDataTypeDisconnect() {
return DATA_TYPE_DISCONNECT;
public static DATA_TYPE getDataTypeConfirm() {
return DATA_TYPE.DATA_TYPE_CONFIRM;
}
/**
* @return {@link ConnectionHandler#DATA_TYPE_MESSAGE
* @return {@link DATA_TYPE}
*/
public static String getDataTypeMessage() {
return DATA_TYPE_MESSAGE;
public static DATA_TYPE getDataTypeDisconnect() {
return DATA_TYPE.DATA_TYPE_DISCONNECT;
}
/**
* @return {@link ConnectionHandler#DATA_TYPE_ERROR}
* @return {@link DATA_TYPE}
*/
public static String getDataTypeError() {
return DATA_TYPE_ERROR;
public static DATA_TYPE getDataTypeMessage() {
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) {

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@ -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 {
private final MessageType type;
public class Message implements Serializable {
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;
}
}

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@ -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();
}
/**

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@ -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();

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@ -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 registry map containing all active connections between server and clients
* @param connection representing the socket connection between server and client
* @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())) {
caseConnect(sender.toString());
} else if (type.toString().equals(getDataTypeConfirm())) {
if (data.getType() == DATA_TYPE.DATA_TYPE_CONNECT) {
caseConnect(data);
} 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())) {
caseMessage(sender.toString(), receiver.toString(), type.toString(), payload.toString());
} else if (type.toString().equals(getDataTypeError())) {
System.err.println("Received error from client (" + sender + "): " + payload);
} else if (data.getType() == DATA_TYPE.DATA_TYPE_MESSAGE) {
caseMessage(data);
} else if (data.getType() == DATA_TYPE.DATA_TYPE_ERROR) {
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 receiver to receive data
* @param type of message
* @param payload data to transmit
* @param 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);
if (!receiver.equals(sender)) {
sendData(sender, receiver, type, payload); //send message to sender if it's a direct message and sender is not receiver.
handler.sendData(data.getSender(), data.getReceiver(), data.getType(), data.getText());
if (!data.getReceiver().equals(data.getSender())) {
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());
}
}
}