Java Doc Server && ServerConnectionHandler

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

@@ -10,7 +10,15 @@ import java.util.Map;
 import java.util.concurrent.locks.Condition;
 import java.util.concurrent.locks.ReentrantLock;
 
-
+/**
+ * This Class represents a Server. The user can start the programm with the port number as a argument.
+ * If no argument has been set the {@link NetworkHandler#DEFAULT_PORT} is used as port number.
+ * After initialising the server:
+ * 1. Starts a Socketserver using the logic given in {@link NetworkHandler.NetworkServer#createServer()}
+ * 2. The server starts to listen for incoming connection using the Logic given in {@link NetworkHandler.NetworkServer#waitForConnection()}
+ * 3. New conections will be atached to a Connectionhandler: {@link ServerConnectionHandler} and placed in a Map containing all active connections {@link Server#connections}
+ *
+ */
 public class Server {
 
     // Server connection
@@ -61,6 +69,11 @@ public class Server {
         }
     }
 
+    /**
+     * The Constructor to create a new instance.
+     * @param serverPort to listen for incoming connections.
+     * @throws IOException thrown if an I/O error occurs when opening the socket.
+     */
     public Server(int serverPort) throws IOException {
         // Open server connection
         System.out.println("Create server connection");
@@ -68,6 +81,10 @@ public class Server {
         System.out.println("Listening on " + networkServer.getHostAddress() + ":" + networkServer.getHostPort());
     }
 
+    /**
+     * With this methode the instance waits for incoming connections. If a client tries to connect to the server.
+     * The connection will be registered in the connection registry if successful.
+     */
     private void start() {
         ReentrantLock mutex = new ReentrantLock();
         Condition nameComplete = mutex.newCondition();
@@ -108,6 +125,9 @@ public class Server {
         System.out.println("Server Stopped.");
     }
 
+    /**
+     * This method will stop the serversocket.
+     */
     public void terminate() {
         try {
             System.out.println("Close server port.");

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

@@ -16,7 +16,31 @@ import java.util.concurrent.locks.Condition;
 import java.util.concurrent.locks.ReentrantLock;
 
 
-
+/**
+ * This class represents the connection between the server and a client and offers the serverside logic.
+ * The ServerConnectionHandler receives data send from the client aswell as sends data to the client.
+ *
+ * The ServeConnectionHandler offers following functionality:
+ *
+ * Evaluating connection attempts from a client by:
+ * 1. Checks if Username is valid (Not used)
+ * 2. Saves Username in {@link ServerConnectionHandler#userName}
+ * 3. Saves the connection in the {@link ServerConnectionHandler#connectionRegistry}
+ *
+ * Processes disconnections from a client by:
+ * 1. Removing the connection from the {@link ServerConnectionHandler#connectionRegistry}
+ * 2. Terminates the socket by calling {@link NetworkHandler.NetworkConnection#close()}
+ *
+ * Processes Messages send from a client by:
+ * 1. Evaluating the reciever by differentiating between broadcast or unicast.
+ * 2. Sending the message accordingly.
+ *
+ * To use this class, start a new instance and start it in a thread.
+ * To constructor needs following parameter:
+ * 1. {@link ch.zhaw.pm2.multichat.protocol.NetworkHandler.NetworkConnection} representing the socket connection between server and client
+ * 2. {@link Map<String,ServerConnectionHandler>} registry to check for all active connections
+ * 3. {@link ReentrantLock @link Condition} to lock server thread to evaluate connection.
+ * */
 public class ServerConnectionHandler extends ConnectionHandler implements Runnable{
     private static final AtomicInteger connectionCounter = new AtomicInteger(0);
     private final int connectionId = connectionCounter.incrementAndGet();
@@ -29,11 +53,21 @@ public class ServerConnectionHandler extends ConnectionHandler implements Runnab
     private String userName = "Anonymous-"+connectionId;
     private State state = NEW;
 
+    /**
+     * Called when runnable gets started in a thread.
+     */
     @Override
     public void run() {
         startReceiving();
     }
 
+    /**
+     * Constructor to intitialize the connection
+     * @param connection representing the socket connection between server and clinet
+     * @param registry map containing all active connections between server and clients
+     * @param mutex to lock thread
+     * @param nameComplete condition to call threads
+     */
     public ServerConnectionHandler(NetworkHandler.NetworkConnection<String> connection,
                                    Map<String,ServerConnectionHandler> registry, ReentrantLock mutex, Condition nameComplete) {
         super();
@@ -45,14 +79,26 @@ public class ServerConnectionHandler extends ConnectionHandler implements Runnab
         this.nameComplete = nameComplete;
     }
 
+    /**
+     *
+     * @return the username of the connected client
+     */
     public String getUserName() {
         return this.userName;
     }
 
+    /**
+     *
+     * @return state of the connection. Poosible states are see {@link ch.zhaw.pm2.multichat.protocol.ConnectionHandler.State}
+     */
     public State getState() {
         return state;
     }
 
+    /**
+     * This methods runs in a whileloop as long as the socket between server and client is available
+     * and the connection State is not ERROR.
+     */
     private void startReceiving() {
             System.out.println("Starting Connection Handler for new User");
             try {
@@ -83,6 +129,9 @@ public class ServerConnectionHandler extends ConnectionHandler implements Runnab
 
     }
 
+    /**
+     * This method will call {@link NetworkHandler.NetworkConnection#close()} to close the Socket.
+     */
     private void stopReceiving() {
         System.out.println("Closing Connection Handler for " + userName);
         try {
@@ -95,6 +144,17 @@ public class ServerConnectionHandler extends ConnectionHandler implements Runnab
         System.out.println("Closed Connection Handler for " + userName);
     }
 
+    /**
+     * This method gets called when socket recieves data. The method checks for the data type and reacts accordingly
+     * If data type:
+     * 1. Connect => checks if username is valid. if valid sends response to client with confirmation.
+     *  If username not valid quits connection by changing status to ERROR.
+     * 2. Confirm => Server should not recieve this kind of message. STDOUT informs about it.
+     * 3. Disconnect => Disconnects connection by removing connection from registry and calling method to terminate socket.
+     * 4. Message => Checks if broadcast or unicast. Sends data accordingly
+     * 5. Error => STDERR message
+     * @param data recieved by the server
+     */
     private void processData(String data)  {
         try {
             Scanner scanner = new Scanner(data);
@@ -125,6 +185,12 @@ public class ServerConnectionHandler extends ConnectionHandler implements Runnab
         }
     }
 
+    /**
+     * This method is called by method {@link ServerConnectionHandler#processData(String)}
+     * Checks if username is valid. if valid sends response to client with confirmation.
+     * @param sender of the payload
+     * @throws ChatProtocolException if username not valid
+     */
     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;
@@ -141,7 +207,7 @@ public class ServerConnectionHandler extends ConnectionHandler implements Runnab
         }
         mutex.lock();
         try {
-            this.userName = sender.toString();
+            this.userName = sender;
             nameComplete.signal();
         }
         finally {
@@ -152,6 +218,11 @@ public class ServerConnectionHandler extends ConnectionHandler implements Runnab
         this.state = CONNECTED;
     }
 
+    /**
+     * This method is called by method {@link ServerConnectionHandler#processData(String)}
+     * Disconnects connection by removing connection from registry and calling method {@link ServerConnectionHandler#stopReceiving()} to terminate socket.
+     * @throws ChatProtocolException if state allready DISCONNECTED.
+     */
     private void caseDisconnect() throws ChatProtocolException {
         if (state == DISCONNECTED)
             throw new ChatProtocolException("Illegal state for disconnect request: " + state);
@@ -163,6 +234,15 @@ public class ServerConnectionHandler extends ConnectionHandler implements Runnab
         this.stopReceiving();
     }
 
+    /**
+     * This method is called by method {@link ServerConnectionHandler#processData(String)}
+     * Checks if broadcast or unicast. Sends data accordingly
+     * @param sender who sent data
+     * @param reciever to recieve data
+     * @param type of message
+     * @param payload data to transmit
+     * @throws ChatProtocolException if state not equal to CONNECT
+     */
     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)) {