ClientChat.java

import java.io.*;
import java.net.*;
import java.awt.*;
import java.util.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.Border;

/**
 * ClientChat.java
 * 
 * Copyright 2015 David Camacho
 * 
 * This program makes the client that connects to the server so that it can chat with other clients
 * It uses a GUI to send information to the client and from the client
 * 
 */


public class ClientChat extends JFrame implements ActionListener{
    private JTextArea jtaSendText;
    private JTextArea jtaRecvText;
    private JButton jbSend;
    private JButton jbExit;
    private JButton jbConnect;
    private Socket socket = null;
    private PrintWriter pw = null;
    private BufferedReader br = null;
    ClientThread clientThread = null;

    public static void main (String args[]) {
        ClientChat cc = new ClientChat();    // starts the ClientChat constructor
    }

  /**
    * ClientChat constructor makes the GUI to interact with  
    */
	
    public ClientChat(){
        super("Chat Client");
        JPanel topP = new JPanel();
        JPanel middleP = new JPanel();
        JPanel bottomP = new JPanel();
        topP.setLayout(new FlowLayout());
        middleP.setLayout(new GridLayout(0,2));
        bottomP.setLayout(new FlowLayout());

        JLabel title = new JLabel("Chatroom Client");
        Font f = new Font("Sans", Font.BOLD, 20);
        title.setFont(f);
        topP.add(title);

        Border border = BorderFactory.createLineBorder(Color.BLACK);
        jtaRecvText = new JTextArea(30,10);
        jtaSendText = new JTextArea(30,10);
        jtaRecvText.setBorder(border);
        jtaSendText.setBorder(border);
        jtaSendText.setLineWrap(true);
        jtaSendText.setWrapStyleWord(true);
        jtaRecvText.setLineWrap(true);
        jtaRecvText.setWrapStyleWord(true);
        jtaRecvText.setEditable(false);
        middleP.add(jtaRecvText);
        middleP.add(jtaSendText);

        jbSend = new JButton("Send");
        jbExit = new JButton("Exit");
        jbConnect = new JButton("Connect");

        jbConnect.addActionListener(this);
        jbSend.addActionListener(this);
        jbExit.addActionListener(this);

        bottomP.add(jbConnect);
        bottomP.add(jbSend);
        bottomP.add(jbExit);

        add(topP, BorderLayout.NORTH);
        add(middleP, BorderLayout.CENTER);
        add(bottomP, BorderLayout.SOUTH);

        setSize(550,400);
        setLocation(200,300);
        setResizable(true);
        setVisible(true);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
	
    public void actionPerformed(ActionEvent ae){

      /**
        *  Once a client clicks the connect button it goes here where we establish the connection
        *  and then starts the ClientThread class where we use threads to read from the server.
        * 
        */
        if(ae.getActionCommand().equals("Connect")){
            try{ 
                socket = new Socket("localhost", 16457);
                jtaRecvText.append("Connected: " + socket);
                jtaRecvText.append("\n");
                br   = new BufferedReader(new InputStreamReader(socket.getInputStream()));
                pw = new PrintWriter(new OutputStreamWriter(socket.getOutputStream()));

                clientThread = new ClientThread();
                clientThread.start();
            }

            catch(UnknownHostException uhe){
                jtaRecvText.append("Host unknown: " + uhe.getMessage()); 
            }
            catch(IOException ioe){  
                jtaRecvText.append("Unexpected exception: " + ioe.getMessage()); 
            }
        }
		
      /**
        *  When the user writes something to the JTextArea and then clicks send it 
        *  sends the string to the server and then resets the text.
        * 
        */
        if(ae.getActionCommand().equals("Send")){
            try{
                String sendMsg;
                sendMsg = jtaSendText.getText();

                pw.println(sendMsg);
                pw.flush();
                jtaSendText.setText("");
            }
            catch(Exception e){
                jtaRecvText.append("Something messed up");
            }
        }
			
      /**
        *  When the user clicks this button it closes the connection and exits the GUi
        */
        if(ae.getActionCommand().equals("Exit")){
            try{
                socket.close();
                System.exit(0);	
            }
            catch(Exception e){
                jtaRecvText.append("Could not exit");
            }
        }
    }
	
    class ClientThread extends Thread{
        String getMsg;

        public ClientThread(){

        }
      /**
        * Once the thread is started when the user clicks connect it goes here to
        * loop the readline so we can get the information from the server and put it in the
        * the JTextArea.
        * 
        */
        public void run(){

            while(true){
                try{
                    getMsg = br.readLine();
                    jtaRecvText.append(getMsg + "\n");
                }
                catch(Exception e){
                    jtaRecvText.append("Something went wrong.");
                }
            }
        }
		
    }
}