jvncclient.java

its good.. for scjp guys......

import java.awt.Color;
import java.awt.FlowLayout;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import java.awt.*;
import javax.swing.JPanel;
import java.awt.event.*;
import java.net.Socket;
import java.net.UnknownHostException;
import java.io.ObjectInputStream;
import java.io.PrintWriter;
import javax.swing.JOptionPane;
import javax.swing.SwingUtilities;


public class JVNCclient extends JFrame implements MouseWheelListener
{
	private JLabel screen;
	private ObjectInputStream in;
	private PrintWriter out;
	private ScreenThread screenThread;
	private ImageIcon i;
	private Socket s;
	private boolean stopped = false;

	public JVNCclient()
	{
		int WIDTH = Toolkit.getDefaultToolkit().getScreenSize().width;
	    int HEIGHT = Toolkit.getDefaultToolkit().getScreenSize().height;
	    
		setTitle("Virtual Network Computing");
		setBackground(Color.white);
		screen = new JLabel();
		getContentPane().setLayout(new FlowLayout(FlowLayout.CENTER, 0, 0));	
		getContentPane().add(screen);
		
		resize(WIDTH,HEIGHT-10);
		
		addMouseListener(new MyMouseAdapter(this));
		addMouseMotionListener(new MyMouseMotionAdapter(this));	
		addKeyListener(new MyKeyAdapter(this));
		
		addWindowListener(new WindowAdapter()
		{
			
			public void windowClosing(WindowEvent we)
			{
				stopped = true;
				screenThread.stopRunning();
				sendAndUpdate(JVNCconstant.CLOSE,0,0);
				System.exit(0);  
			}
			
		});

		
		String serverName =	JOptionPane.showInputDialog(this, "Enter Server name :", "Server", JOptionPane.INFORMATION_MESSAGE);
		
		try
		{
			s = new Socket(serverName.trim(), 1166);
			if (s==null)
			{
				System.out.println("No I/O");
				System.exit(0);
			}
			else
			{	
				in = new ObjectInputStream(s.getInputStream());
				out = new PrintWriter(s.getOutputStream());
				
				screenThread = new ScreenThread();
			}
		}
		
		catch (Exception ex)
		{
			JOptionPane.showMessageDialog(null,"Server not found on PORT number 1166");
			System.exit(0);
		}
		
	}
	
	public void updateScreen(final ImageIcon i)
	{	
		javax.swing.SwingUtilities.invokeLater(new Runnable()
		{
			public void run()
			{
                screen.repaint();
				screen.setIcon(i);
			}
		});
	}
	
	
	private void sendAndUpdate(int type,int arg1, int arg2)
	{
		String s = "" + type + "|" + arg1 + "|" + arg2;
		out.println(s);
		out.flush();
	}
	
	
	
	class MyMouseAdapter extends MouseAdapter
	{
		JVNCclient jvnc;
	
		public MyMouseAdapter(JVNCclient jvnc)
		{
			this.jvnc = jvnc;
		}
		public void mousePressed(MouseEvent e)
		{
			sendAndUpdate(JVNCconstant.MOUSE_PRESS, e.getX(),e.getY());
		}

		public void mouseReleased(MouseEvent e)
		{
			sendAndUpdate(JVNCconstant.MOUSE_RELEASE,0,0);
		}
	}
	
	class MyMouseMotionAdapter extends MouseMotionAdapter
	{
		JVNCclient jvnc;
	
		public MyMouseMotionAdapter(JVNCclient jvnc)
		{
			this.jvnc = jvnc;
		}
		
		public void mouseDragged(MouseEvent e)
		{
			sendAndUpdate(JVNCconstant.MOUSE_MOVE, e.getX(), e.getY());		
		}

		public void mouseMoved(MouseEvent e)
		{
			sendAndUpdate(JVNCconstant.MOUSE_MOVE,e.getX(), e.getY());
		}
	}
		
	public void mouseWheelMoved(MouseWheelEvent e)
	{
		sendAndUpdate(JVNCconstant.MOUSE_WHEEL,e.getScrollAmount(),0);
	}
	
	
	
	class MyKeyAdapter extends KeyAdapter
	{
		JVNCclient jvnc;
	
		public MyKeyAdapter(JVNCclient jvnc)
		{
			this.jvnc = jvnc;
		}
		
		public void keyPressed(KeyEvent ke)
		{
			int key; 
			
			key = ke.getKeyCode();
		
			if(key==ke.VK_ENTER)
				sendAndUpdate(JVNCconstant.KEY_PRESS_EVENTS,ke.VK_ENTER,0);
			else if(key==ke.VK_F1)
				sendAndUpdate(JVNCconstant.KEY_PRESS_EVENTS,ke.VK_F1,0);
			else if(key==ke.VK_ESCAPE)
				sendAndUpdate(JVNCconstant.KEY_PRESS_EVENTS,ke.VK_ESCAPE,0);
		}	
	}

	public static void main(String argv[])
	{
		JVNCclient f = new JVNCclient();
		f.setVisible(true);
		f.show();
	}
	
	private class ScreenThread implements Runnable
	{
		Thread t;
		private  boolean keepRunning;
		
		ScreenThread()
		{
			keepRunning = true;
			t = new Thread(this,"Screen Thread");
			t.start();
		}

		public void run()
		{
			while (keepRunning)
			{
				try
				{		
					if(stopped ==false)	
					{
					if((i = (ImageIcon)in.readObject())!=null)
					{
						updateScreen(i);		
						Thread.sleep(1000);
						i=null;
					}
					}
					else
					{
						keepRunning = false;
						in.close();
					}
				}
				catch(InterruptedException e)
				{
					System.out.println("Thread Interrupted");
				}
				catch(OutOfMemoryError e)
				{
					e.toString();
					JOptionPane.showMessageDialog(null,"JVM can not able to allocate Memory");
					System.exit(0);
				}
				catch (ClassNotFoundException ex)
				{
					ex.printStackTrace();
				}
				catch (Exception ex)
				{
					ex.printStackTrace();
					JOptionPane.showMessageDialog(null,"Server is stoped");
					System.exit(0);
				}
			}
		}
		
		public void stopRunning()
		{
			keepRunning = false;
		}
	}
		
}