Shrink code in the ConnectionHandlers

Fixes issue #37

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

@@ -29,12 +29,15 @@ public class ClientConnectionHandler extends ConnectionHandler implements Runnab
         super();
         this.messages = messages;
         state = new SimpleObjectProperty<>(State.NEW);
-        serverAddress = new SimpleStringProperty();
-        serverPort = new SimpleIntegerProperty();
+        serverAddress = new SimpleStringProperty(NetworkHandler.DEFAULT_ADDRESS.getCanonicalHostName());
+        serverPort = new SimpleIntegerProperty(NetworkHandler.DEFAULT_PORT);
+        this.userName = new SimpleStringProperty(null);
     }
 
     public void initialize(String serverAddress, int serverPort, String userName) throws IOException {
-        state = new SimpleObjectProperty<>(NEW);
+        state.set(NEW);
+        this.serverAddress.set(serverAddress);
+        this.serverPort.set(serverPort);
         setConnection(NetworkHandler.openConnection(serverAddress, serverPort));
         this.userName = new SimpleStringProperty((userName == null || userName.isBlank())? USER_NONE : userName);
     }
@@ -96,66 +99,24 @@ public class ClientConnectionHandler extends ConnectionHandler implements Runnab
 
     private void processData(String data) {
         try {
-            // parse data content
             Scanner scanner = new Scanner(data);
-            String sender = null;
-            String reciever = null;
-            String type = null;
-            String payload = null;
-            if (scanner.hasNextLine()) {
-                sender = scanner.nextLine();
-            } else {
-                throw new ChatProtocolException("No Sender found");
-            }
-            if (scanner.hasNextLine()) {
-                reciever = scanner.nextLine();
-            } else {
-                throw new ChatProtocolException("No Reciever found");
-            }
-            if (scanner.hasNextLine()) {
-                type = scanner.nextLine();
-            } else {
-                throw new ChatProtocolException("No Type found");
-            }
-            if (scanner.hasNextLine()) {
-                payload = scanner.nextLine();
-            }
+            StringBuilder sender = new StringBuilder();
+            StringBuilder reciever = new StringBuilder();
+            StringBuilder type = new StringBuilder();
+            StringBuilder payload = new StringBuilder();
+            super.processData(scanner,sender,reciever,type,payload);
+
             // dispatch operation based on type parameter
-            if (type.equals(getDataTypeConnect())) {
+            if (type.toString().equals(getDataTypeConnect())) {
                 System.err.println("Illegal connect request from server");
-            } else if (type.equals(getDataTypeConfirm())) {
-                if (state.get() == CONFIRM_CONNECT) {
-                    this.userName.set(reciever);
-                    this.serverPort.set(getConnection().getRemotePort());
-                    this.serverAddress.set(getConnection().getRemoteHost());
-                    messages.addMessage(new Message(Message.MessageType.INFO,sender,reciever,payload));
-                    System.out.println("CONFIRM: " + payload);
-                    this.setState(CONNECTED);
-                } else if (state.get() == CONFIRM_DISCONNECT) {
-                    messages.addMessage(new Message(Message.MessageType.INFO,sender,reciever,payload));
-                    System.out.println("CONFIRM: " + payload);
-                    this.setState(DISCONNECTED);
-                } else {
-                    System.err.println("Got unexpected confirm message: " + payload);
-                }
-            } else if (type.equals(getDataTypeDisconnect())) {
-                if (state.get() == DISCONNECTED) {
-                    System.out.println("DISCONNECT: Already in disconnected: " + payload);
-                    return;
-                }
-                messages.addMessage(new Message(Message.MessageType.INFO,sender,reciever,payload));
-                System.out.println("DISCONNECT: " + payload);
-                this.setState(DISCONNECTED);
-            } else if (type.equals(getDataTypeMessage())) {
-                if (state.get() != CONNECTED) {
-                    System.out.println("MESSAGE: Illegal state " + state + " for message: " + payload);
-                    return;
-                }
-                messages.addMessage(new Message(Message.MessageType.MESSAGE,sender,reciever,payload));
-                System.out.println("MESSAGE: From " + sender + " to " + reciever + ": "+  payload);
-            } else if (type.equals(getDataTypeError())) {
-                messages.addMessage(new Message(Message.MessageType.ERROR,sender,reciever,payload));
-                System.out.println("ERROR: " + payload);
+            } else if (type.toString().equals(getDataTypeConfirm())) {
+                caseConfirm(sender.toString(), reciever.toString(), payload.toString());
+            } else if (type.toString().equals(getDataTypeDisconnect())) {
+                caseDisconnect(sender.toString(),reciever.toString(),payload.toString());
+            } else if (type.toString().equals(getDataTypeMessage())) {
+                caseMessage(sender.toString(),reciever.toString(),payload.toString());
+            } else if (type.toString().equals(getDataTypeError())) {
+                caseError(sender.toString(), reciever.toString(), payload.toString());
             } else {
                 System.out.println("Unknown data type received: " + type);
             }
@@ -165,27 +126,47 @@ public class ClientConnectionHandler extends ConnectionHandler implements Runnab
         }
     }
 
-    private void sendData(String sender, String receiver, String type, String payload) {
-        if (getConnection().isAvailable()) {
-            new StringBuilder();
-            String data = new StringBuilder()
-                .append(sender+"\n")
-                .append(receiver+"\n")
-                .append(type+"\n")
-                .append(payload+"\n")
-                .toString();
-            try {
-                getConnection().send(data);
-            } catch (SocketException e) {
-                System.err.println("Connection closed: " + e.getMessage());
-            } catch (EOFException e) {
-                System.out.println("Connection terminated by remote");
-            } catch(IOException e) {
-                System.err.println("Communication error: " + e.getMessage());
-            }
+    private void caseConfirm(String sender, String reciever, String payload) {
+        if (state.get() == CONFIRM_CONNECT) {
+            this.userName.set(reciever);
+            this.serverPort.set(getConnection().getRemotePort());
+            this.serverAddress.set(getConnection().getRemoteHost());
+            messages.addMessage(new Message(Message.MessageType.INFO,sender,reciever,payload));
+            System.out.println("CONFIRM: " + payload);
+            this.setState(CONNECTED);
+        } else if (state.get() == CONFIRM_DISCONNECT) {
+            messages.addMessage(new Message(Message.MessageType.INFO,sender,reciever,payload));
+            System.out.println("CONFIRM: " + payload);
+            this.setState(DISCONNECTED);
+        } else {
+            System.err.println("Got unexpected confirm message: " + payload);
         }
     }
 
+    private void caseDisconnect(String sender, String reciever, String payload) {
+        if (state.get() == DISCONNECTED) {
+            System.out.println("DISCONNECT: Already in disconnected: " + payload);
+            return;
+        }
+        messages.addMessage(new Message(Message.MessageType.INFO,sender,reciever,payload));
+        System.out.println("DISCONNECT: " + payload);
+        this.setState(DISCONNECTED);
+    }
+
+    private void caseMessage(String sender, String reciever, String payload) {
+        if (state.get() != CONNECTED) {
+            System.out.println("MESSAGE: Illegal state " + state + " for message: " + payload);
+            return;
+        }
+        messages.addMessage(new Message(Message.MessageType.MESSAGE,sender,reciever,payload));
+        System.out.println("MESSAGE: From " + sender + " to " + reciever + ": "+  payload);
+    }
+
+    private void caseError(String sender, String reciever, String payload) {
+        messages.addMessage(new Message(Message.MessageType.ERROR,sender,reciever,payload));
+        System.out.println("ERROR: " + payload);
+    }
+
     public void connect() throws ChatProtocolException {
         if (state.get() != NEW) throw new ChatProtocolException("Illegal state for connect: " + state);
         this.sendData(userName.get(), USER_NONE, getDataTypeConnect(),null);
@@ -215,5 +196,4 @@ public class ClientConnectionHandler extends ConnectionHandler implements Runnab
             return false;
         }
     }
-
 }

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

@@ -1,5 +1,10 @@
 package ch.zhaw.pm2.multichat.protocol;
 
+import java.io.EOFException;
+import java.io.IOException;
+import java.net.SocketException;
+import java.util.Scanner;
+
 public abstract class ConnectionHandler {
     private NetworkHandler.NetworkConnection<String> connection;
 
@@ -14,7 +19,7 @@ public abstract class ConnectionHandler {
     public static final String USER_ALL = "*";
 
     public enum State {
-        NEW, CONFIRM_CONNECT, CONNECTED, CONFIRM_DISCONNECT, DISCONNECTED;
+        NEW, CONFIRM_CONNECT, CONNECTED, CONFIRM_DISCONNECT, DISCONNECTED, ERROR;
     }
 
     public static String getDataTypeConnect() {
@@ -44,4 +49,47 @@ public abstract class ConnectionHandler {
     protected void setConnection(NetworkHandler.NetworkConnection<String> connection) {
         this.connection = connection;
     }
+
+    protected void processData(Scanner scanner, StringBuilder sender, StringBuilder reciever, StringBuilder type, StringBuilder payload) throws ChatProtocolException {
+        // parse data content
+        if (scanner.hasNextLine()) {
+            sender.append(scanner.nextLine());
+        } else {
+            throw new ChatProtocolException("No Sender found");
+        }
+        if (scanner.hasNextLine()) {
+            reciever.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());
+        }
+    }
+
+    protected void sendData(String sender, String receiver, String type, String payload) {
+        if (connection.isAvailable()) {
+            new StringBuilder();
+            String data = new StringBuilder()
+                    .append(sender+"\n")
+                    .append(receiver+"\n")
+                    .append(type+"\n")
+                    .append(payload+"\n")
+                    .toString();
+            try {
+                getConnection().send(data);
+            } catch (SocketException e) {
+                System.err.println("Connection closed: " + e.getMessage());
+            } catch (EOFException e) {
+                System.out.println("Connection terminated by remote");
+            } catch(IOException e) {
+                System.err.println("Communication error: " + e.getMessage());
+            }
+        }
+    }
 }

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

@@ -1,5 +1,6 @@
 package ch.zhaw.pm2.multichat.server;
 
+import ch.zhaw.pm2.multichat.protocol.ConnectionHandler;
 import ch.zhaw.pm2.multichat.protocol.NetworkHandler;
 
 import java.io.IOException;
@@ -75,11 +76,17 @@ public class Server {
                  mutex.lock();
                  try {
                      nameComplete.await();
-                     System.out.println(String.format("Connected new Client %s with IP:Port <%s:%d>",
-                             connectionHandler.getUserName(),
-                             connection.getRemoteHost(),
-                             connection.getRemotePort()
-                     ));
+                     if(connectionHandler.getState() == ConnectionHandler.State.ERROR) {
+                         System.out.println(String.format("Connecting failed for new Client with IP:Port <%s:%d>.\nReason: Name already taken.",
+                                 connection.getRemoteHost(),
+                                 connection.getRemotePort()));
+                     }
+                     else {
+                         System.out.println(String.format("Connected new Client %s with IP:Port <%s:%d>",
+                                 connectionHandler.getUserName(),
+                                 connection.getRemoteHost(),
+                                 connection.getRemotePort()));
+                     }
                  }
                 finally {
                      mutex.unlock();

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

@@ -8,7 +8,6 @@ import ch.zhaw.pm2.multichat.protocol.NetworkHandler;
 import java.io.EOFException;
 import java.io.IOException;
 import java.net.SocketException;
-import java.util.HashMap;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Scanner;
@@ -50,11 +49,15 @@ public class ServerConnectionHandler extends ConnectionHandler implements Runnab
         return this.userName;
     }
 
+    public State getState() {
+        return state;
+    }
+
     private void startReceiving() {
             System.out.println("Starting Connection Handler for new User");
             try {
                 System.out.println("Start receiving data...");
-                while (getConnection().isAvailable()) {
+                while (getConnection().isAvailable() && !(state == ERROR)) {
                     String data = getConnection().receive();
                     processData(data);
                 }
@@ -72,7 +75,11 @@ public class ServerConnectionHandler extends ConnectionHandler implements Runnab
             } catch (ClassNotFoundException e) {
                 System.err.println("Received object of unknown type: " + e.getMessage());
             }
+        if (state == ERROR) {
+            System.out.println("Stopping Connection Handler for Rejected Client");
+        } else {
             System.out.println("Stopping Connection Handler for " + userName);
+        }
 
     }
 
@@ -83,112 +90,94 @@ public class ServerConnectionHandler extends ConnectionHandler implements Runnab
             getConnection().close();
             System.out.println("Stopped receiving data.");
         } catch (IOException e) {
-            System.err.println("Failed to close connection." + e);
+            System.err.println("Failed to close connection." + e.getMessage());
         }
         System.out.println("Closed Connection Handler for " + userName);
     }
 
     private void processData(String data)  {
         try {
-            // parse data content
             Scanner scanner = new Scanner(data);
-            String sender = null;
-            String reciever = null;
-            String type = null;
-            String payload = null;
-            if (scanner.hasNextLine()) {
-                sender = scanner.nextLine();
-            } else {
-                throw new ChatProtocolException("No Sender found");
-            }
-            if (scanner.hasNextLine()) {
-                reciever = scanner.nextLine();
-            } else {
-                throw new ChatProtocolException("No Reciever found");
-            }
-            if (scanner.hasNextLine()) {
-                type = scanner.nextLine();
-            } else {
-                throw new ChatProtocolException("No Type found");
-            }
-            if (scanner.hasNextLine()) {
-                payload = scanner.nextLine();
-            }
+            StringBuilder sender = new StringBuilder();
+            StringBuilder reciever = new StringBuilder();
+            StringBuilder type = new StringBuilder();
+            StringBuilder payload = new StringBuilder();
+            super.processData(scanner,sender,reciever,type,payload);
 
             // dispatch operation based on type parameter
-            if (type.equals(getDataTypeConnect())) {
-                if (this.state != NEW) throw new ChatProtocolException("Illegal state for connect request: " + state);
-                if (sender == null || sender.isBlank()) sender = this.userName;
-                if (connectionRegistry.containsKey(sender))
-                    throw new ChatProtocolException("User name already taken: " + sender);
-                mutex.lock();
-                try {
-                    this.userName = sender;
-                    nameComplete.signal();
-                }
-                finally {
-                    mutex.unlock();
-                }
-                connectionRegistry.put(userName, this);
-                sendData(USER_NONE, userName, getDataTypeConfirm(), "Registration successfull for " + userName);
-                this.state = CONNECTED;
-            } else if (type.equals(getDataTypeConfirm())) {
+            if (type.toString().equals(getDataTypeConnect())) {
+                caseConnect(sender.toString());
+            } else if (type.toString().equals(getDataTypeConfirm())) {
                 System.out.println("Not expecting to receive a CONFIRM request from client");
-            } else if (type.equals(getDataTypeDisconnect())) {
-                if (state == DISCONNECTED)
-                    throw new ChatProtocolException("Illegal state for disconnect request: " + state);
-                if (state == CONNECTED) {
-                    connectionRegistry.remove(this.userName);
-                }
-                sendData(USER_NONE, userName, getDataTypeConfirm(), "Confirm disconnect of " + userName);
-                this.state = DISCONNECTED;
-                this.stopReceiving();
-            } else if (type.equals(getDataTypeMessage())) {
-                if (state != CONNECTED) throw new ChatProtocolException("Illegal state for message request: " + state);
-                if (USER_ALL.equals(reciever)) {
-                    for (ServerConnectionHandler handler : connectionRegistry.values()) {
-                        handler.sendData(sender, reciever, type, payload);
-                    }
-                } else {
-                    ServerConnectionHandler handler = connectionRegistry.get(reciever);
-                    if (handler != null) {
-                        handler.sendData(sender, reciever, type, payload);
-                        if(!reciever.equals(sender)){
-                            sendData(sender, reciever, type, payload); //send message to sender if it's a direct message and sender is not receiver.
-                        }
-                    } else {
-                        this.sendData(USER_NONE, userName, getDataTypeError(), "Unknown User: " + reciever);
-                    }
-                }
-            } else if (type.equals(getDataTypeError())) {
+            } else if (type.toString().equals(getDataTypeDisconnect())) {
+                caseDisconnect();
+            } else if (type.toString().equals(getDataTypeMessage())) {
+                caseMessage(sender.toString(), reciever.toString(), type.toString(), payload.toString());
+            } else if (type.toString().equals(getDataTypeError())) {
                 System.err.println("Received error from client (" + sender + "): " + payload);
             } else {
                 System.err.println("Unknown data type received: " + type);
 
             }
         } catch(ChatProtocolException e) {
-            System.out.println("Error while processing data" + e.getMessage());
+            System.out.println("Error while processing data " + e.getMessage());
             sendData(USER_NONE, userName, getDataTypeError(), e.getMessage());
         }
     }
 
-    private void sendData(String sender, String receiver, String type, String payload) {
-        if (getConnection().isAvailable()) {
-            new StringBuilder();
-            String data = new StringBuilder()
-                .append(sender+"\n")
-                .append(receiver+"\n")
-                .append(type+"\n")
-                .append(payload+"\n")
-                .toString();
+    private void caseConnect(String sender) throws ChatProtocolException {
+        if (this.state != NEW) throw new ChatProtocolException("Illegal state for connect request: " + state);
+        if (sender.isBlank()) sender = this.userName;
+        if (connectionRegistry.containsKey(sender)) {
+            mutex.lock();
             try {
-                getConnection().send(data);
-            } catch (SocketException e) {
-                System.out.println("Connection closed: " + e.getMessage());
-            } catch (EOFException e) {
-                System.out.println("Connection terminated by remote");
-            } catch(IOException e) {
-                System.out.println("Communication error: " + e.getMessage());
+                state = ERROR;
+                nameComplete.signal();
+            }
+            finally {
+                mutex.unlock();
+            }
+            throw new ChatProtocolException("User name already taken: " + sender);
+        }
+        mutex.lock();
+        try {
+            this.userName = sender.toString();
+            nameComplete.signal();
+        }
+        finally {
+            mutex.unlock();
+        }
+        connectionRegistry.put(userName, this);
+        sendData(USER_NONE, userName, getDataTypeConfirm(), "Registration successfull for " + userName);
+        this.state = CONNECTED;
+    }
+
+    private void caseDisconnect() throws ChatProtocolException {
+        if (state == DISCONNECTED)
+            throw new ChatProtocolException("Illegal state for disconnect request: " + state);
+        if (state == CONNECTED) {
+            connectionRegistry.remove(this.userName);
+        }
+        sendData(USER_NONE, userName, getDataTypeConfirm(), "Confirm disconnect of " + userName);
+        this.state = DISCONNECTED;
+        this.stopReceiving();
+    }
+
+    private void caseMessage(String sender, String reciever, String type, String payload) throws ChatProtocolException{
+        if (state != CONNECTED) throw new ChatProtocolException("Illegal state for message request: " + state);
+        if (USER_ALL.equals(reciever)) {
+            for (ServerConnectionHandler handler : connectionRegistry.values()) {
+                handler.sendData(sender, reciever, type, payload);
+            }
+        } else {
+            ServerConnectionHandler handler = connectionRegistry.get(reciever);
+            if (handler != null) {
+                handler.sendData(sender, reciever, type, payload);
+                if(!reciever.equals(sender)){
+                    sendData(sender, reciever, type, payload); //send message to sender if it's a direct message and sender is not receiver.
+                }
+            } else {
+                this.sendData(USER_NONE, userName, getDataTypeError(), "Unknown User: " + reciever);
             }
         }
     }