The code contains 5 classes that you can cut & paste in a directory on your PC and it should work.
The 5 classes are:
- – ChatMessage.java
- – Server.java
- – Client.java
- – ServerGUI.java
- – ClientGUI.java
ChatMessage.java
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 |
import java.io.*; /* * This class defines the different type of messages that will be exchanged between the * Clients and the Server. * When talking from a Java Client to a Java Server a lot easier to pass Java objects, no * need to count bytes or to wait for a line feed at the end of the frame */ public class ChatMessage implements Serializable { protected static final long serialVersionUID = 1112122200 L; // The different types of message sent by the Client // WHOISIN to receive the list of the users connected // MESSAGE an ordinary message // LOGOUT to disconnect from the Server static final int WHOISIN = 0, MESSAGE = 1, LOGOUT = 2; private int type; private String message; // constructor ChatMessage(int type, String message) { this.type = type; this.message = message; } // getters int getType() { return type; } String getMessage() { return message; } } |
You can start the Server by typing
> java Server
at the console prompt. That will execute it in console mode and the server will wait for connection on port 1500. To use another port pass the port number to use as first parameter to the command
> java Server 1200
will ask the Server to listen on port 1200.
You can use <CTRL>C to stop the server.
Server.java
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 |
import java.io.*; import java.net.*; import java.text.SimpleDateFormat; import java.util.*; /* * The server that can be run both as a console application or a GUI */ public class Server { // a unique ID for each connection private static int uniqueId; // an ArrayList to keep the list of the Client private ArrayList & lt; ClientThread & gt; al; // if I am in a GUI private ServerGUI sg; // to display time private SimpleDateFormat sdf; // the port number to listen for connection private int port; // the boolean that will be turned of to stop the server private boolean keepGoing; /* * server constructor that receive the port to listen to for connection as parameter * in console */ public Server(int port) { this(port, null); } public Server(int port, ServerGUI sg) { // GUI or not this.sg = sg; // the port this.port = port; // to display hh:mm:ss sdf = new SimpleDateFormat("HH:mm:ss"); // ArrayList for the Client list al = new ArrayList & lt; ClientThread & gt; (); } public void start() { keepGoing = true; /* create socket server and wait for connection requests */ try { // the socket used by the server ServerSocket serverSocket = new ServerSocket(port); // infinite loop to wait for connections while (keepGoing) { // format message saying we are waiting display("Server waiting for Clients on port " + port + "."); Socket socket = serverSocket.accept(); // accept connection // if I was asked to stop if (!keepGoing) break; ClientThread t = new ClientThread(socket); // make a thread of it al.add(t); // save it in the ArrayList t.start(); } // I was asked to stop try { serverSocket.close(); for (int i = 0; i & lt; al.size(); ++i) { ClientThread tc = al.get(i); try { tc.sInput.close(); tc.sOutput.close(); tc.socket.close(); } catch (IOException ioE) { // not much I can do } } } catch (Exception e) { display("Exception closing the server and clients: " + e); } } // something went bad catch (IOException e) { String msg = sdf.format(new Date()) + " Exception on new ServerSocket: " + e + "\n"; display(msg); } } /* * For the GUI to stop the server */ protected void stop() { keepGoing = false; // connect to myself as Client to exit statement // Socket socket = serverSocket.accept(); try { new Socket("localhost", port); } catch (Exception e) { // nothing I can really do } } /* * Display an event (not a message) to the console or the GUI */ private void display(String msg) { String time = sdf.format(new Date()) + " " + msg; if (sg == null) System.out.println(time); else sg.appendEvent(time + "\n"); } /* * to broadcast a message to all Clients */ private synchronized void broadcast(String message) { // add HH:mm:ss and \n to the message String time = sdf.format(new Date()); String messageLf = time + " " + message + "\n"; // display message on console or GUI if (sg == null) System.out.print(messageLf); else sg.appendRoom(messageLf); // append in the room window // we loop in reverse order in case we would have to remove a Client // because it has disconnected for (int i = al.size(); --i & gt; = 0;) { ClientThread ct = al.get(i); // try to write to the Client if it fails remove it from the list if (!ct.writeMsg(messageLf)) { al.remove(i); display("Disconnected Client " + ct.username + " removed from list."); } } } // for a client who logoff using the LOGOUT message synchronized void remove(int id) { // scan the array list until we found the Id for (int i = 0; i & lt; al.size(); ++i) { ClientThread ct = al.get(i); // found it if (ct.id == id) { al.remove(i); return; } } } /* * To run as a console application just open a console window and: * > java Server * > java Server portNumber * If the port number is not specified 1500 is used */ public static void main(String[] args) { // start server on port 1500 unless a PortNumber is specified int portNumber = 1500; switch (args.length) { case 1: try { portNumber = Integer.parseInt(args[0]); } catch (Exception e) { System.out.println("Invalid port number."); System.out.println("Usage is: > java Server [portNumber]"); return; } case 0: break; default: System.out.println("Usage is: > java Server [portNumber]"); return; } // create a server object and start it Server server = new Server(portNumber); server.start(); } /** One instance of this thread will run for each client */ class ClientThread extends Thread { // the socket where to listen/talk Socket socket; ObjectInputStream sInput; ObjectOutputStream sOutput; // my unique id (easier for deconnection) int id; // the Username of the Client String username; // the only type of message a will receive ChatMessage cm; // the date I connect String date; // Constructore ClientThread(Socket socket) { // a unique id id = ++uniqueId; this.socket = socket; /* Creating both Data Stream */ System.out.println("Thread trying to create Object Input/Output Streams"); try { // create output first sOutput = new ObjectOutputStream(socket.getOutputStream()); sInput = new ObjectInputStream(socket.getInputStream()); // read the username username = (String) sInput.readObject(); display(username + " just connected."); } catch (IOException e) { display("Exception creating new Input/output Streams: " + e); return; } // have to catch ClassNotFoundException // but I read a String, I am sure it will work catch (ClassNotFoundException e) {} date = new Date().toString() + "\n"; } // what will run forever public void run() { // to loop until LOGOUT boolean keepGoing = true; while (keepGoing) { // read a String (which is an object) try { cm = (ChatMessage) sInput.readObject(); } catch (IOException e) { display(username + " Exception reading Streams: " + e); break; } catch (ClassNotFoundException e2) { break; } // the messaage part of the ChatMessage String message = cm.getMessage(); // Switch on the type of message receive switch (cm.getType()) { case ChatMessage.MESSAGE: broadcast(username + ": " + message); break; case ChatMessage.LOGOUT: display(username + " disconnected with a LOGOUT message."); keepGoing = false; break; case ChatMessage.WHOISIN: writeMsg("List of the users connected at " + sdf.format(new Date()) + "\n"); // scan al the users connected for (int i = 0; i & lt; al.size(); ++i) { ClientThread ct = al.get(i); writeMsg((i + 1) + ") " + ct.username + " since " + ct.date); } break; } } // remove myself from the arrayList containing the list of the // connected Clients remove(id); close(); } // try to close everything private void close() { // try to close the connection try { if (sOutput != null) sOutput.close(); } catch (Exception e) {} try { if (sInput != null) sInput.close(); } catch (Exception e) {}; try { if (socket != null) socket.close(); } catch (Exception e) {} } /* * Write a String to the Client output stream */ private boolean writeMsg(String msg) { // if Client is still connected send the message to it if (!socket.isConnected()) { close(); return false; } // write the message to the stream try { sOutput.writeObject(msg); } // if an error occurs, do not abort just inform the user catch (IOException e) { display("Error sending message to " + username); display(e.toString()); } return true; } } } |
The Client class.
Once the Server is started you can start the Client by typing
> java Client
at the console port. That will start the Client with the username Anonymous on the localhost using port 1500. So the command is equivalent to
> java Client Anonymous 1500 localhost
You can specify any of the parameter in order
> java Client Me == > java Client Me 1500 localhost
> java Client Me 1200 == > java Client Me 1200 localhost
> java Client Me 1200 12.14.13.14 == > java Client Me 1200 12.14.13.14
Once the Client started in console mode you can enter:
– LOGOUT to logout and close the connections
– WHOISIN to receive the list of the user connected to the server
– anything else is a message that will be broadcast, with your username, to all the Clients on the room
Client.java
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 |
import java.net.*; import java.io.*; import java.util.*; /* * The Client that can be run both as a console or a GUI */ public class Client { // for I/O private ObjectInputStream sInput; // to read from the socket private ObjectOutputStream sOutput; // to write on the socket private Socket socket; // if I use a GUI or not private ClientGUI cg; // the server, the port and the username private String server, username; private int port; /* * Constructor called by console mode * server: the server address * port: the port number * username: the username */ Client(String server, int port, String username) { // which calls the common constructor with the GUI set to null this(server, port, username, null); } /* * Constructor call when used from a GUI * in console mode the ClienGUI parameter is null */ Client(String server, int port, String username, ClientGUI cg) { this.server = server; this.port = port; this.username = username; // save if we are in GUI mode or not this.cg = cg; } /* * To start the dialog */ public boolean start() { // try to connect to the server try { socket = new Socket(server, port); } // if it failed not much I can so catch (Exception ec) { display("Error connectiong to server:" + ec); return false; } String msg = "Connection accepted " + socket.getInetAddress() + ":" + socket.getPort(); display(msg); /* Creating both Data Stream */ try { sInput = new ObjectInputStream(socket.getInputStream()); sOutput = new ObjectOutputStream(socket.getOutputStream()); } catch (IOException eIO) { display("Exception creating new Input/output Streams: " + eIO); return false; } // creates the Thread to listen from the server new ListenFromServer().start(); // Send our username to the server this is the only message that we // will send as a String. All other messages will be ChatMessage objects try { sOutput.writeObject(username); } catch (IOException eIO) { display("Exception doing login : " + eIO); disconnect(); return false; } // success we inform the caller that it worked return true; } /* * To send a message to the console or the GUI */ private void display(String msg) { if (cg == null) System.out.println(msg); // println in console mode else cg.append(msg + "\n"); // append to the ClientGUI JTextArea (or whatever) } /* * To send a message to the server */ void sendMessage(ChatMessage msg) { try { sOutput.writeObject(msg); } catch (IOException e) { display("Exception writing to server: " + e); } } /* * When something goes wrong * Close the Input/Output streams and disconnect not much to do in the catch clause */ private void disconnect() { try { if (sInput != null) sInput.close(); } catch (Exception e) {} // not much else I can do try { if (sOutput != null) sOutput.close(); } catch (Exception e) {} // not much else I can do try { if (socket != null) socket.close(); } catch (Exception e) {} // not much else I can do // inform the GUI if (cg != null) cg.connectionFailed(); } /* * To start the Client in console mode use one of the following command * > java Client * > java Client username * > java Client username portNumber * > java Client username portNumber serverAddress * at the console prompt * If the portNumber is not specified 1500 is used * If the serverAddress is not specified "localHost" is used * If the username is not specified "Anonymous" is used * > java Client * is equivalent to * > java Client Anonymous 1500 localhost * are eqquivalent * * In console mode, if an error occurs the program simply stops * when a GUI id used, the GUI is informed of the disconnection */ public static void main(String[] args) { // default values int portNumber = 1500; String serverAddress = "localhost"; String userName = "Anonymous"; // depending of the number of arguments provided we fall through switch (args.length) { // > javac Client username portNumber serverAddr case 3: serverAddress = args[2]; // > javac Client username portNumber case 2: try { portNumber = Integer.parseInt(args[1]); } catch (Exception e) { System.out.println("Invalid port number."); System.out.println("Usage is: > java Client [username] [portNumber] [serverAddress]"); return; } // > javac Client username case 1: userName = args[0]; // > java Client case 0: break; // invalid number of arguments default: System.out.println("Usage is: > java Client [username] [portNumber] {serverAddress]"); return; } // create the Client object Client client = new Client(serverAddress, portNumber, userName); // test if we can start the connection to the Server // if it failed nothing we can do if (!client.start()) return; // wait for messages from user Scanner scan = new Scanner(System.in); // loop forever for message from the user while (true) { System.out.print("> "); // read message from user String msg = scan.nextLine(); // logout if message is LOGOUT if (msg.equalsIgnoreCase("LOGOUT")) { client.sendMessage(new ChatMessage(ChatMessage.LOGOUT, "")); // break to do the disconnect break; } // message WhoIsIn else if (msg.equalsIgnoreCase("WHOISIN")) { client.sendMessage(new ChatMessage(ChatMessage.WHOISIN, "")); } else { // default to ordinary message client.sendMessage(new ChatMessage(ChatMessage.MESSAGE, msg)); } } // done disconnect client.disconnect(); } /* * a class that waits for the message from the server and append them to the JTextArea * if we have a GUI or simply System.out.println() it in console mode */ class ListenFromServer extends Thread { public void run() { while (true) { try { String msg = (String) sInput.readObject(); // if console mode print the message and add back the prompt if (cg == null) { System.out.println(msg); System.out.print("> "); } else { cg.append(msg); } } catch (IOException e) { display("Server has close the connection: " + e); if (cg != null) cg.connectionFailed(); break; } // can't happen with a String object but need the catch anyhow catch (ClassNotFoundException e2) {} } } } } |
The GUI is a simple GUI using JTextArea don’t expect fancy fonts, colors, Icons,… I kept it as simple as possible.
The ClientGUI class.
This is a simple GUI. It is a BorderLayout with in the NORTH region an editable JTextField containing the port number the Server should listen to and 2 buttons to Start/Stop the Server.
The CENTER region contains two JScrollPane both containing a JTextArea. The first JTextArea contains the messages exchanged in the ChatRoom, basically what the Clients see. The secong JTextArea contains event messages: who login, who logout, error messages, and so on
To execute that GUI type
> java ServerGUI
at the console prompt
ServerGUI.Java
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 |
import javax.swing.*; import java.awt.*; import java.awt.event.*; /* * The server as a GUI */ public class ServerGUI extends JFrame implements ActionListener, WindowListener { private static final long serialVersionUID = 1 L; // the stop and start buttons private JButton stopStart; // JTextArea for the chat room and the events private JTextArea chat, event; // The port number private JTextField tPortNumber; // my server private Server server; // server constructor that receive the port to listen to for connection as parameter ServerGUI(int port) { super("Chat Server"); server = null; // in the NorthPanel the PortNumber the Start and Stop buttons JPanel north = new JPanel(); north.add(new JLabel("Port number: ")); tPortNumber = new JTextField(" " + port); north.add(tPortNumber); // to stop or start the server, we start with "Start" stopStart = new JButton("Start"); stopStart.addActionListener(this); north.add(stopStart); add(north, BorderLayout.NORTH); // the event and chat room JPanel center = new JPanel(new GridLayout(2, 1)); chat = new JTextArea(80, 80); chat.setEditable(false); appendRoom("Chat room.\n"); center.add(new JScrollPane(chat)); event = new JTextArea(80, 80); event.setEditable(false); appendEvent("Events log.\n"); center.add(new JScrollPane(event)); add(center); // need to be informed when the user click the close button on the frame addWindowListener(this); setSize(400, 600); setVisible(true); } // append message to the two JTextArea // position at the end void appendRoom(String str) { chat.append(str); chat.setCaretPosition(chat.getText().length() - 1); } void appendEvent(String str) { event.append(str); event.setCaretPosition(chat.getText().length() - 1); } // start or stop where clicked public void actionPerformed(ActionEvent e) { // if running we have to stop if (server != null) { server.stop(); server = null; tPortNumber.setEditable(true); stopStart.setText("Start"); return; } // OK start the server int port; try { port = Integer.parseInt(tPortNumber.getText().trim()); } catch (Exception er) { appendEvent("Invalid port number"); return; } // ceate a new Server server = new Server(port, this); // and start it as a thread new ServerRunning().start(); stopStart.setText("Stop"); tPortNumber.setEditable(false); } // entry point to start the Server public static void main(String[] arg) { // start server default port 1500 new ServerGUI(1500); } /* * If the user click the X button to close the application * I need to close the connection with the server to free the port */ public void windowClosing(WindowEvent e) { // if my Server exist if (server != null) { try { server.stop(); // ask the server to close the conection } catch (Exception eClose) {} server = null; } // dispose the frame dispose(); System.exit(0); } // I can ignore the other WindowListener method public void windowClosed(WindowEvent e) {} public void windowOpened(WindowEvent e) {} public void windowIconified(WindowEvent e) {} public void windowDeiconified(WindowEvent e) {} public void windowActivated(WindowEvent e) {} public void windowDeactivated(WindowEvent e) {} /* * A thread to run the Server */ class ServerRunning extends Thread { public void run() { server.start(); // should execute until if fails // the server failed stopStart.setText("Start"); tPortNumber.setEditable(true); appendEvent("Server crashed\n"); server = null; } } } |
The ClientGUI class.
This is the GUI for the Client. Also a BorderLayout. In the NORTH region two JTextField to enter the host name of the Server and the port number it is listening to.
The CENTER region contains a JScrollPane with a JTextArea that contains the messages exchanged in the ChatRoom.
The SOUTH region conatisn 3 buttons: “Login”, “Logout”, “Who is in”.
To start the Client type
>java ClientGUI
at the command prompt
ClientGUI.java
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 |
import javax.swing.*; import java.awt.*; import java.awt.event.*; /* * The Client with its GUI */ public class ClientGUI extends JFrame implements ActionListener { private static final long serialVersionUID = 1L; // will first hold "Username:", later on "Enter message" private JLabel label; // to hold the Username and later on the messages private JTextField tf; // to hold the server address an the port number private JTextField tfServer, tfPort; // to Logout and get the list of the users private JButton login, logout, whoIsIn; // for the chat room private JTextArea ta; // if it is for connection private boolean connected; // the Client object private Client client; // the default port number private int defaultPort; private String defaultHost; // Constructor connection receiving a socket number ClientGUI(String host, int port) { super("Chat Client"); defaultPort = port; defaultHost = host; // The NorthPanel with: JPanel northPanel = new JPanel(new GridLayout(3,1)); // the server name anmd the port number JPanel serverAndPort = new JPanel(new GridLayout(1,5, 1, 3)); // the two JTextField with default value for server address and port number tfServer = new JTextField(host); tfPort = new JTextField("" + port); tfPort.setHorizontalAlignment(SwingConstants.RIGHT); serverAndPort.add(new JLabel("Server Address: ")); serverAndPort.add(tfServer); serverAndPort.add(new JLabel("Port Number: ")); serverAndPort.add(tfPort); serverAndPort.add(new JLabel("")); // adds the Server an port field to the GUI northPanel.add(serverAndPort); // the Label and the TextField label = new JLabel("Enter your username below", SwingConstants.CENTER); northPanel.add(label); tf = new JTextField("Anonymous"); tf.setBackground(Color.WHITE); northPanel.add(tf); add(northPanel, BorderLayout.NORTH); // The CenterPanel which is the chat room ta = new JTextArea("Welcome to the Chat room\n", 80, 80); JPanel centerPanel = new JPanel(new GridLayout(1,1)); centerPanel.add(new JScrollPane(ta)); ta.setEditable(false); add(centerPanel, BorderLayout.CENTER); // the 3 buttons login = new JButton("Login"); login.addActionListener(this); logout = new JButton("Logout"); logout.addActionListener(this); logout.setEnabled(false); // you have to login before being able to logout whoIsIn = new JButton("Who is in"); whoIsIn.addActionListener(this); whoIsIn.setEnabled(false); // you have to login before being able to Who is in JPanel southPanel = new JPanel(); southPanel.add(login); southPanel.add(logout); southPanel.add(whoIsIn); add(southPanel, BorderLayout.SOUTH); setDefaultCloseOperation(EXIT_ON_CLOSE); setSize(600, 600); setVisible(true); tf.requestFocus(); } // called by the Client to append text in the TextArea void append(String str) { ta.append(str); ta.setCaretPosition(ta.getText().length() - 1); } // called by the GUI is the connection failed // we reset our buttons, label, textfield void connectionFailed() { login.setEnabled(true); logout.setEnabled(false); whoIsIn.setEnabled(false); label.setText("Enter your username below"); tf.setText("Anonymous"); // reset port number and host name as a construction time tfPort.setText("" + defaultPort); tfServer.setText(defaultHost); // let the user change them tfServer.setEditable(false); tfPort.setEditable(false); // don't react to a after the username tf.removeActionListener(this); connected = false; } /* * Button or JTextField clicked */ public void actionPerformed(ActionEvent e) { Object o = e.getSource(); // if it is the Logout button if(o == logout) { client.sendMessage(new ChatMessage(ChatMessage.LOGOUT, "")); return; } // if it the who is in button if(o == whoIsIn) { client.sendMessage(new ChatMessage(ChatMessage.WHOISIN, "")); return; } // ok it is coming from the JTextField if(connected) { // just have to send the message client.sendMessage(new ChatMessage(ChatMessage.MESSAGE, tf.getText())); tf.setText(""); return; } if(o == login) { // ok it is a connection request String username = tf.getText().trim(); // empty username ignore it if(username.length() == 0) return; // empty serverAddress ignore it String server = tfServer.getText().trim(); if(server.length() == 0) return; // empty or invalid port numer, ignore it String portNumber = tfPort.getText().trim(); if(portNumber.length() == 0) return; int port = 0; try { port = Integer.parseInt(portNumber); } catch(Exception en) { return; // nothing I can do if port number is not valid } // try creating a new Client with GUI client = new Client(server, port, username, this); // test if we can start the Client if(!client.start()) return; tf.setText(""); label.setText("Enter your message below"); connected = true; // disable login button login.setEnabled(false); // enable the 2 buttons logout.setEnabled(true); whoIsIn.setEnabled(true); // disable the Server and Port JTextField tfServer.setEditable(false); tfPort.setEditable(false); // Action listener for when the user enter a message tf.addActionListener(this); } } // to start the whole thing the server public static void main(String[] args) { new ClientGUI("localhost", 1500); } } |
