ChatClient.java

//Jonathan Nelson
//ChatClient.java
 
import java.util.*;
import java.io.*;
import java.net.*;
import javax.swing.text.*;
import java.awt.event.*;


public class ChatClient extends javax.swing.JFrame {

	private static Socket socket;
	private String serverAddress;
	private int port = 1850;
	private static InputStream in = null;
	private static OutputStream out = null;
	private static PrintWriter pout = null;
	private static BufferedReader console = null;
	private static BufferedReader inReader = null;
	//private static String inMessage = null;
	private static String outMessage = null;
	private static boolean nowConnected = false;
	
	


    /**
     * Creates new form ChatClient
     */
    public ChatClient() {
        initComponents();
		//setDoubleBuffered(true);
    }

    /**
     * This method is called from within the constructor to initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is always
     * regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
    private void initComponents() {

        serverName = new javax.swing.JTextField();
        serverLabel = new javax.swing.JLabel();
        uNameLabel = new javax.swing.JLabel();
        uName = new javax.swing.JTextField();
        connectButton = new javax.swing.JButton();
        jSplitPane1 = new javax.swing.JSplitPane();
        jScrollPane1 = new javax.swing.JScrollPane();
        chatLogArea = new javax.swing.JTextArea();
        jScrollPane2 = new javax.swing.JScrollPane();
        userListArea = new javax.swing.JTextArea();
        messageText = new javax.swing.JTextField();
        sendButton = new javax.swing.JButton();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        serverLabel.setText("Server");

        uNameLabel.setText("User Name");

        uName.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                uNameActionPerformed(evt);
            }
        });

        connectButton.setText("Connect");
        connectButton.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                connectButtonActionPerformed(evt);
            }
        });

        jSplitPane1.setDividerLocation(600);

        chatLogArea.setColumns(20);
        chatLogArea.setRows(5);
        jScrollPane1.setViewportView(chatLogArea);

        jSplitPane1.setLeftComponent(jScrollPane1);

        userListArea.setColumns(20);
        userListArea.setRows(5);
        jScrollPane2.setViewportView(userListArea);

        jSplitPane1.setRightComponent(jScrollPane2);

	//enable double buffereing on the scroll panes
	//jScrollPane1.setDoubleBufferd(true);
	//jScrollPane2.setDoubleBufferd(true);

        messageText.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                messageTextActionPerformed(evt);
            }
        });

        sendButton.setText("Send");
        sendButton.addActionListener(new java.awt.event.ActionListener() {
			public void actionPerformed(java.awt.event.ActionEvent evt) {
				sendButtonActionPerformed(evt);
			}
		});

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addContainerGap()
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addComponent(jSplitPane1)
                    .addGroup(layout.createSequentialGroup()
                        .addComponent(serverLabel)
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                        .addComponent(serverName, javax.swing.GroupLayout.PREFERRED_SIZE, 125, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addGap(75, 75, 75)
                        .addComponent(uNameLabel)
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                        .addComponent(uName, javax.swing.GroupLayout.PREFERRED_SIZE, 126, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 253, Short.MAX_VALUE)
                        .addComponent(connectButton))
                    .addGroup(layout.createSequentialGroup()
                        .addComponent(messageText)
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                        .addComponent(sendButton)))
                .addContainerGap())
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addContainerGap()
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(serverName, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(serverLabel)
                    .addComponent(uNameLabel)
                    .addComponent(uName, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(connectButton))
                .addGap(18, 18, 18)
                .addComponent(jSplitPane1, javax.swing.GroupLayout.DEFAULT_SIZE, 532, Short.MAX_VALUE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(messageText, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(sendButton))
                .addContainerGap())
        );
		
		jScrollPane1.getVerticalScrollBar().addAdjustmentListener(new AdjustmentListener(){
			public void adjustmentValueChanged(AdjustmentEvent e){
			chatLogArea.select(chatLogArea.getHeight()+100000,0);
		}});
		
        pack();
    }// </editor-fold>                        

	private void sendButtonActionPerformed(java.awt.event.ActionEvent evt) {
		if (messageText.getText() != null) {
			String message = messageText.getText();
			messageText.setText("");
			sendMsg(message);
		}
	}

    private void uNameActionPerformed(java.awt.event.ActionEvent evt) {                                      
        doConnectDisconnect();
    }                                     

    private void connectButtonActionPerformed(java.awt.event.ActionEvent evt) {                                              
        doConnectDisconnect();
    }                                             

    private void messageTextActionPerformed(java.awt.event.ActionEvent evt) {                                           
        if (messageText.getText() != null) {
			String message = messageText.getText();
			messageText.setText("");
			sendMsg(message);
		}
    }                                           

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) throws Exception {
        /* Create and display the form */
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new ChatClient().setVisible(true);
            }
        });
        
        try {
			Thread.sleep(1000);
		} catch (InterruptedException e) {
			//hope and pray
		}
		
		DefaultCaret caret = (DefaultCaret)chatLogArea.getCaret();
		caret.setUpdatePolicy(DefaultCaret.ALWAYS_UPDATE);
		
        //System.out.println("main() called");
        
        while (true) {
			//System.out.println("Checking to see if we are connected");
			if (nowConnected) {
				//System.out.println("main() still connected");
				try {
					if (inReader.ready()) {
						//System.out.println("reading line from socket");
						String inMessage = inReader.readLine();
						//System.out.println(inMessage);
						if (inMessage.startsWith("USER")) {
							sendMsg(uName.getText());
						} else if (inMessage.startsWith("WELCOME")) {
							writeLog("Connection successful");
							messageText.requestFocus();
						} else if (inMessage.startsWith("GOODBYE")) {
							if (inMessage.endsWith("BADUSER")) {
								writeLog("That username is already in use");
							} else if (inMessage.endsWith("TIMEOUT")) {
								writeLog("The connection timed out.");
							} else if (inMessage.endsWith("SHUTDOWN")) {
								writeLog("The server is shutting down.");
							}
							writeLog("Server has closed the connection");
							disconnect();
							inMessage = null;
						} else if (inMessage.startsWith("LIST")) {
							updateUserList(inMessage);
						} else {
							//System.out.println("Message was not a control message");
							writeLog(inMessage);
						}
										
					}
				} catch (IOException e) {
					//Under heavy load the server seems to forget about some users
					System.err.println("Error accessing BufferedReader inReader");
					writeLog("Error trying to read from the connection, trying to reconnect");
					disconnect();
					connect();
				}
			}
			Thread.sleep(100);
		}
	}
    
    private void doConnectDisconnect() {
		if (connectButton.getText().equals("Connect"))
			connect();
		else
			disconnect();
	}
	
	private static void connect() {
		if (connectButton.getText().equals("Connect")) {
			try {
				if (!uName.getText().equals("") && !serverName.getText().equals("") ) {
					//Disable access to buttons and text fields
					connectButton.setText("Disconnect");
					serverName.disable();
					serverName.updateUI();
					uName.disable();
					uName.updateUI();
					connectButton.disable();
					
					writeLog("Connecting to " + serverName.getText() + " on port 1850");
					socket = new Socket(serverName.getText(), 1850);
					//socket.setKeepAlive();
					
					in = socket.getInputStream();
					out = socket.getOutputStream();
					pout = new PrintWriter( out, true);
			
					console = new BufferedReader( new InputStreamReader(System.in));
					inReader = new BufferedReader(new InputStreamReader(in));
					outMessage = new String();
					//inMessage = new String();
					connectButton.enable();
					nowConnected = true;
				} else {
					writeLog("Server address and username can not be blank");
				}
			} catch (Exception e) {
				//This will catch both IOExceptions as well as HostNotFoundExceptions
				writeLog("Cannot connect to host");
				//Enable access to buttons and text fields
				connectButton.setText("Connect");
				serverName.enable();
				serverName.updateUI();
				uName.enable();
				uName.updateUI();
				connectButton.enable();
			}
		}
	}
	
	private static void disconnect() {
		if (connectButton.getText().equals("Disconnect")) {
			writeLog("Disconnecting from server");
			try {
				sendMsg("DISCONNECT");
				socket.close();
				updateUserList("");
			} catch (IOException e) {
				//It's fine if we can't send the DISCONNECT message.
			} finally {
				in = null;
				out = null;
				pout = null;
				socket = null;
				console = null;
				inReader = null;
				outMessage = null;
				nowConnected = false;
				
				
				//Enable access to buttons and text fields
				connectButton.setText("Connect");
				serverName.enable();
				serverName.updateUI();
				uName.enable();
				uName.updateUI();
				connectButton.enable();
				
			}
		}
	}
	
	private static void sendMsg(String message) {
		if (nowConnected && pout != null) {
			pout.println(message);
		}
	}
	
	private static void writeLog(String line) {
		//DefaultCaret caret = (DefaultCaret)chatLogArea.getCaret();
		//caret.setUpdatePolicy(DefaultCaret.ALWAYS_UPDATE);
		
		if (line != null || !line.equals(""));
			chatLogArea.append(line + "\n");
			
	}
	
	private static void updateUserList(String users) {
		//System.out.println("updating user list");
		//The first 5 characters of the string will be "LIST "
		if (users != null) {
			if (users.equals("")) {
				userListArea.setText("");
			} else {
				users = users.substring(5, users.length());
				StringTokenizer tokens = new StringTokenizer(users);
				userListArea.setText("");
				while (tokens.hasMoreTokens()) {
					userListArea.append(tokens.nextToken() + "\n");
				}
			}
		}
	}
			
    
    // Variables declaration - do not modify                     
    private static javax.swing.JTextArea chatLogArea;
    private static javax.swing.JButton connectButton;
    private javax.swing.JScrollPane jScrollPane1;
    private javax.swing.JScrollPane jScrollPane2;
    private javax.swing.JSplitPane jSplitPane1;
    private static javax.swing.JTextField messageText;
    private javax.swing.JButton sendButton;
    private javax.swing.JLabel serverLabel;
    private static javax.swing.JTextField serverName;
    private static javax.swing.JTextField uName;
    private javax.swing.JLabel uNameLabel;
    private static javax.swing.JTextArea userListArea;
    // End of variables declaration                   
}