jmessenger.java

an instant messenger written in java (client)

import javax.swing.*;
import java.util.*;

public class JMessenger implements LoginListener, ChatListener, PrivateMessageListener, TransportListener
{
    public String loginname;  // use to record the input name 
    private JTransport contact;
    private JLogin login = null;
    private JChat chat = null;
    
    private LinkedList privateMessages = new LinkedList();     // use java.util.LinkedList
    
    public JMessenger()
    {
    contact = new JTransport(this);
    login = new JLogin(this);
    chat = new JChat(this);
    
    login.setVisible(true);
    }
    
    // TransportListener
    public void onConnect()
    {
        contact.authenticateUser(loginname);
    }
    
    public void onUserValid()
    {
        login.setVisible(false);
        chat.setTitle("Messenger -- Logged in --> " + loginname);
        chat.showChat();
    }
        
    public void onUserJoin(String name)
    {
        chat.userJoin(name);
    }
    
    public void onUserLeave(String name)
    {
        chat.userLeft(name);
        for (int i=0; i<privateMessages.size(); i++)
        {
            if (((JPrivateMessage)privateMessages.get(i)).remotename.equalsIgnoreCase(name))
            {
                ((JPrivateMessage)privateMessages.get(i)).userLeft();
                break;
            }
        }
    }
    
    public void onMessageRev(String from, String message)
    {
        // if no private chat window open yet
        JPrivateMessage first;
        boolean available = false;
        
        for (int i=0; i<privateMessages.size(); i++)
        {
            if (((JPrivateMessage)privateMessages.get(i)).remotename.equalsIgnoreCase(from))
            {
                available = true;
                ((JPrivateMessage)privateMessages.get(i)).revMessage(message);
            }
        }

        if (!available)    // then create a new private chat window
        {
            first = new JPrivateMessage(this, loginname, from);
            first.revMessage(message);
            privateMessages.add(first);
        }
    }
    
    public void onMessageRevFromAll(String from, String message)
    {
        chat.revMessage(from, message);    
    }
    
    public void onSendMessageError(int id, String description)
    {
        System.out.println("Error! Fail to send." + description);
    }
    
    public void onLostConnection()
    {
        System.out.println("Lost connection");
        
        chat.setVisible(false);
        
        for (int i=0; i<privateMessages.size(); i++)     // i=1??
            ((JPrivateMessage)privateMessages.get(i)).dispose();
        
        privateMessages.clear();
        login.setVisible(true);
    }
    
    // PrivateMessageListener
    public void onSendMessage(String to, String message)
    {
        contact.sendMessage(to, message);
    }
    
    public void onClosePrivateMessage(String remotename)
    {
        for(int i = 0; i < privateMessages.size(); i++)
        {
            if(((JPrivateMessage)privateMessages.get(i)).remotename.equalsIgnoreCase(remotename))
            {
                ((JPrivateMessage)privateMessages.get(i)).dispose();
                privateMessages.remove(i);
                break;
            }
        }
    }
    
    // ChatListener
    public void onSendMessageToAll(String message)
    {   
        contact.sendMessageToAll(message);
    }
    
    public void onInitiatePrivateMessage(String remoteUser)
    {   
        if(remoteUser.equals(loginname))    // try to talk with oneself
            JOptionPane.showMessageDialog(null, "You can't talk to yourself!", "Contact Error", JOptionPane.ERROR_MESSAGE);
        else if (!remoteUser.equalsIgnoreCase(loginname))
        {
            JPrivateMessage initial;
            boolean available = false;
            
            for (int i=0; i<privateMessages.size(); i++)
            {
                if (((JPrivateMessage)privateMessages.get(i)).remotename.equalsIgnoreCase(remoteUser))
                {
                    available = true;
                    ((JPrivateMessage)privateMessages.get(i)).toFront();
                }
            }

            if (!available)    // then create a new private chat window
            {
                initial = new JPrivateMessage(this, loginname, remoteUser);
                privateMessages.add(initial);
            }     
        }
    }
   
    // LoginListener
    public void onConnectRequest(String host, int port, String username)
    {
        loginname = username;    // record the login name of the user
        contact.connect(host, port);
    }

    public void onLoginCancel()
    {
        System.exit(0);
    }
    
    public static void main(String argv[])
    {
        JMessenger main = new JMessenger();
    }
}