working v 1.0

src/javaChat/ChatClient.java

@@ -0,0 +1,90 @@
+package javaChat;
+
+import java.net.* ;
+import java.io.* ;
+
+public class ChatClient
+    {
+
+    /**
+     * 
+     *
+     * @param args
+     * @throws IOException
+     */
+    public static void main( String[] args ) throws IOException
+        {
+        // Get server IP
+        BufferedReader keyboard = new BufferedReader( new InputStreamReader( System.in ) ) ;
+        System.out.print( "\nPlease enter the IP of the desired server: " ); // GUI: IP BOX
+        
+        String serverIP = keyboard.readLine() ;
+        
+        // Open your connection to a server, at port 6789
+        Socket socket = new Socket( serverIP , 6789 ) ;
+        
+        // Create communication streams
+        DataInputStream dataStreamIn = new DataInputStream( socket.getInputStream() ) ;    
+        DataOutputStream dataStreamOut = new DataOutputStream( socket.getOutputStream() ) ;
+       
+        // Establish connection, make user-name
+        System.out.print( "\nConnection established,\nPlease enter a username: " ) ;       
+        String username = keyboard.readLine() ;
+        dataStreamOut.writeUTF( username ) ;
+        
+        /////////////////////////
+        //// Program Running ////
+        /////////////////////////
+        
+        // Thread for sending messages
+        Thread sendMessage = new Thread(new Runnable()
+            {
+            @Override
+            public void run() 
+                {
+                System.out.print( "\n-= Type /help for a list of commands =-" ) ;
+                while( true )
+                    {
+                    try
+                        {
+                        String messageOut = keyboard.readLine() ;
+                        dataStreamOut.writeUTF( messageOut ) ;
+                        }
+                    catch( IOException x )
+                        {
+                        x.printStackTrace() ;
+                        System.exit( 0 ) ;
+                        }
+                    }
+                }
+            }) ;
+        
+        // Thread for receiving messages
+        Thread receiveMessage = new Thread( new Runnable()
+            {
+            
+            @Override
+            public void run()
+               {
+               while( true )
+                   {
+                   try
+                       {
+                       String messageIn = dataStreamIn.readUTF() ;
+                       System.out.printf( "%n%s\n", messageIn ) ;
+                       }
+                   catch( IOException x )
+                       {
+                       x.printStackTrace() ;
+                       System.exit( 0 ) ;
+                       } 
+                   }
+               }
+            });
+        
+        // Begin threads
+        sendMessage.start() ;
+        receiveMessage.start() ;
+        }
+    }
+	// end class ChatClient

src/javaChat/ChatServer.java

@@ -0,0 +1,237 @@
+package javaChat;
+
+import java.net.* ;
+import java.util.* ;
+import java.io.* ;
+
+public class ChatServer
+    {
+
+    // List of all active users in Server
+    static ArrayList<ClientHandler> userList = new ArrayList<>() ;
+    
+    /**
+     * Accepts Client requests to join chat server, and
+     * creates new thread for each individual client.
+     *
+     * @param args
+     * @throws IOException
+     */
+    public static void main( String[] args ) throws IOException
+        {
+        
+        // Register service on port 6789
+        ServerSocket serverSocket = new ServerSocket( 6789 ) ;
+        Socket socket = null ;
+        
+        System.out.println( "\nServer established. Awaiting connections..." ) ;
+        
+        // Accept client requests
+        while( true )
+            {
+            socket = serverSocket.accept() ;
+            
+            DataOutputStream dataStreamOut = new DataOutputStream( socket.getOutputStream() ) ;        
+            DataInputStream dataStreamIn = new DataInputStream ( socket.getInputStream() ) ;
+            
+            System.out.println( "\nClient connection detected, requesting username..." ) ;
+            String username = dataStreamIn.readUTF() ;
+            
+            ClientHandler handle = new ClientHandler( socket, username, dataStreamOut, dataStreamIn ) ;
+            
+            System.out.println( "\nCreating new thread...\n" ) ;
+            Thread thread = new Thread( handle ) ;
+            
+            userList.add( handle ) ;
+            
+            thread.start() ;
+            
+            }
+        }
+
+    }
+    // end class ChatClient
+
+
+
+
+    // This class manages the actual messages being sent around
+    @SuppressWarnings( "javadoc" )
+    class ClientHandler implements Runnable
+        {
+        
+        Socket socket ;
+        String username ;
+        final DataOutputStream dataStreamOut ;
+        final DataInputStream dataStreamIn ;
+        boolean loggedIn ;
+        private ArrayList<ClientHandler> userList ;
+    
+        
+    /**
+     * Constructor
+     * @param s : client socket
+     * @param user  : client's user-name
+     * @param dos : data stream to client
+     * @param dis : data stream from client
+     */
+    public ClientHandler( Socket s, String user, 
+                          DataOutputStream dos,
+                          DataInputStream dis )
+        {
+        this.username = user ;
+        this.socket = s ;
+        this.dataStreamOut = dos ;
+        this.dataStreamIn = dis ;
+        this.loggedIn = true ;
+        
+        }
+    
+    @Override
+    public void run() 
+        {
+        
+        // Note the connection of the new user
+        String announcement = String.format( "-= User \"%s\" has successfully connected =-\n", this.username ) ;
+        System.out.println( announcement ) ;
+       
+        // Distribute announcement to entire server
+        distributeAll( announcement ) ;
+            
+        // Message management
+        String message = "" ;      
+        while( true ) 
+            {
+                // Read incoming messages
+                try
+                    {
+                    message = this.dataStreamIn.readUTF() ;
+                    }
+                catch ( IOException x )
+                    {
+                    x.printStackTrace() ;
+                    }      
+                
+                // Check message for user commands, returns TRUE is user quits
+                if( commands(message, this) )
+                    {
+                    break ;
+                    }
+                
+                // Print the message server-side
+                message = String.format( "%s: %s", this.username, message ) ;
+                System.out.println( message ) ;
+                
+                // Distribute the message to all users
+                sendMessage( message ) ;
+                // end try
+            
+            }
+        
+            try
+                {
+                this.loggedIn = false ;
+                this.socket.close() ;
+                }
+            catch( IOException x )
+                {
+                x.printStackTrace() ;
+                }
+        }
+ 
+    
+    // This method manages the usage of user-commands
+    public boolean commands(String message, ClientHandler user) 
+        {
+        String[] commands = new String[] {"/help", "/quit", "/userlist"} ;
+        
+        try {
+            
+            // Quit command terminates connection, with an announcement
+            if( message.equals( "/quit" )) 
+                {
+                String announcement = String.format( "\n-= \"%s\" has disconnected =- \n", user.username ) ;
+                System.out.println( announcement ) ;
+                distributeAll( announcement ) ;
+                return true ;
+                }
+            
+            if( message.equals( "/userlist" ) ) 
+                {
+                user.dataStreamOut.writeUTF( "Current list of users in the server: " ) ;
+                for( ClientHandler users : ChatServer.userList )
+                    {                    
+                    if( !users.loggedIn )
+                        {
+                        continue ;
+                        }
+                    
+                    user.dataStreamOut.writeUTF( users.username ) ;
+                    
+                    }   
+                }
+            
+            if( message.contentEquals( "/help" ) )
+                {
+                user.dataStreamOut.writeUTF( "\nAll available commands: " );
+                for(int i = 0; i < commands.length; i++ ) 
+                    {
+                    user.dataStreamOut.writeUTF( commands[i] );
+                    }
+                
+                    user.dataStreamOut.writeUTF( "\n" ) ;
+                }
+        }
+        
+        catch( IOException x )
+            {
+            System.out.println( x ) ;
+            }
+        
+        return false ;
+        }
+    
+    
+    // Convenience method to send messages (but not to the user that's sending the message)
+    private void sendMessage(String message)
+        {
+        try
+            {      
+            for( ClientHandler users : ChatServer.userList )
+                {                    
+                if( !users.loggedIn || users.equals( this ) )
+                    {
+                    continue ;
+                    }
+                users.dataStreamOut.writeUTF( "> " + message ) ;
+                }    
+            }
+        catch ( IOException x )
+            {
+            x.printStackTrace() ;
+            }
+        }
+    
+    
+    // Convenience method to distribute messages to all clients (announcements)
+    private void distributeAll(String message)
+        {
+        try
+            {      
+            for( ClientHandler users : ChatServer.userList )
+                {                    
+                if( !users.loggedIn )
+                    {
+                    continue ;
+                    }
+                users.dataStreamOut.writeUTF( message ) ;
+                }    
+            }
+        catch ( IOException x )
+            {
+            x.printStackTrace() ;
+            }
+        }
+
+    }
+    // end class ClientHandler

src/module-info.java

@@ -6,4 +6,5 @@
  *
  */
 module javaChat
-    {}
+    {
+    requires java.desktop;}