Java using applet pro

Generate Bouncing Lines Using Applet

import java.awt.*;

import java.applet.Applet; 

public class BouncingLines extends Applet implements Runnable

{

Thread runner = null; 

final static int Width  = 200;

final static int Height = 100;

           Image    image;

Graphics graphics;

int[] x1;

int[] y1;

int[] x2;

int[] y2;

int dx1 = 2 + (int)( 3 * Math.random() );

int dy1 = 2 + (int)( 3 * Math.random() );

int dx2 = 2 + (int)( 3 * Math.random() );

int dy2 = 2 + (int)( 3 * Math.random() );

static int first = 0;

final static int Lines = 50;

public void init()

{

x1 = new int[Lines];

y1 = new int[Lines];

x2 = new int[Lines];

y2 = new int[Lines];

x1[0] = (int)( Width  * Math.random() );

y1[0] = (int)( Height * Math.random() );

x2[0] = (int)( Width  * Math.random() );

y2[0] = (int)( Height * Math.random() );

for ( int i = 1; i < Lines; i++ )

{

x1[i] = x1[0];

y1[i] = y1[0];

x2[i] = x2[0];

y2[i] = y2[0];

}

image    = createImage( Width,Height );

graphics = image.getGraphics();

} 

public void start()

{

if ( runner == null )

{ 

runner = new Thread( this );

runner.start();

}

}

public void stop()

{

if ( runner != null && runner.isAlive() )

runner.stop();

runner = null;

}

public void run()

 {

while (runner != null)

{ 

repaint();

try

{

Thread.sleep( 20 ); 

}

 catch ( InterruptedException e )

{

   }

  }

}

public void paint( Graphics g )

 {

  update( g );

 }

public void update( Graphics g )

 {

graphics.setColor( Color.black );

graphics.fillRect( 0, 0, Width, Height );

for(int r=4;r<=9;r++)

{             

graphics.setColor( Color.green );    

int line = first;       

for ( int i = 0; i < Lines; i++ )

 { 

graphics.drawLine( x1[line], y1[line],x2[line], y2[line] );

line++;

if ( line == Lines ) line = 0;

}       

line = first;

first--;         

if ( first < 0 ) first = Lines - 1;       

x1[first] = x1[line];

y1[first] = y1[line];

x2[first] = x2[line];

y2[first] = y2[line];

if (x1[first] + dx2 < Width)

x1[first] += dx1;

else

dx1 = -(2 + (int)( 3 * Math.random() ));   

if (x1[first] + dx1 >= 0)

x1[first] += dx1;

else

dx1 = 2 + (int)( 3 * Math.random() );

if (y1[first] + dy1 < Height)

y1[first] += dy1;

else

dy1 = -(2 + (int)( 3 * Math.random() ));       

if (y1[first] + dy1 >= 0)

y1[first] += dy1;

else

dy1 = 2 + (int)( 3 * Math.random() );       

if (x2[first] + dx2 < Width)

x2[first] += dx2;

else

dx2 = -(2 + (int)( 3 * Math.random() ));   

if (x2[first] + dx2 >= 0)

x2[first] += dx2;

else

dx2 = 2 + (int)( 3 * Math.random() );

f (y2[first] + dy2 < Height)

y2[first] += dy2;

else

dy2 = -(2 + (int)( 3 * Math.random() ));       

if (y2[first] + dy2 >= 0)

y2[first] += dy2;

else

dy2 = 2 + (int)( 3 * Math.random() );     

g.drawImage( image, 0, 0, this );

     }

   }

}

Get Applet Context

import java.applet.Applet;

import java.applet.AppletContext;

public class GetAppletContextExample extends Applet

{

public void init()

{

AppletContext appContext = getAppletContext();                                 

   }

}

Get Applet Directory URL or Code Base

import java.applet.Applet;

import java.awt.Graphics;

import java.net.URL;

public class GetCodeBaseExample extends Applet

{

public void paint(Graphics g)

{

URL appletDir = getCodeBase();

g.drawString(appletDir.toString(), 50, 50);           

   }

}

Get Applet Info

import java.applet.Applet;

import java.awt.Graphics;

public class GetAppletInfoExample extends Applet

{

public void paint(Graphics g)

{             

String info = getAppletInfo();

g.drawString(info,50,50);

}

public String getAppletInfo()

{

String info = "";

info = info + "GetAppletInfoExample";

info = info + "java-examples ";           

return info;

   }

}