SOURCE CODE

import java.applet.Applet;
import java.awt.*;

public class RandomC extends Applet implements Runnable{
	String alphabet;
	TextField output1, output2, output3;
	Button button1, button2, button3;

	Thread thread1, thread2, thread3;

	boolean suspend1, suspend2, suspend3;

	public void init()
	{
		alphabet = new String ("ABCDEFGHIJKLMNOPQRSTUVXYZ" );
		output1 = new TextField (10);
		output1.setEditable (false);
		output2 = new TextField (10);
		output2.setEditable (false);
		output3 = new TextField (10);
		output3.setEditable (false);
		button1 = new Button ( "Suspend/Resume 1" );
		button2 = new Button ( "Suspend/Resume 2" );
		button3 = new Button ( "Suspend/Resume 3" );

		add (output1);
		add (button1);
		add (output2);
		add (button2);
		add (output3);
		add (button3);		
	}

	public void start ()
	{
		thread1 = new Thread (this, "Thread 1" );
		thread2 = new Thread (this, "Thread 2" );
		thread3 = new Thread (this, "Thread 3" );

		thread1.start();
		thread2.start();
		thread3.start();
	}

	public void stop ()
	{
	// stops threads every time stop is called (i.e. when user browses another Web page)
		thread1.stop();
		thread2.stop();
		thread3.stop();
	}

	public boolean action ( Event event, Object obj)
	{
		if ( event.target == button1 )
			if ( suspend1)
			{
				thread1.resume();
				suspend1 = false;
			}
			else
			{
				thread1.suspend();
				output1.setText( "suspended" );
				suspend1 = true;
			}
		else if ( event.target == button2 )
			if ( suspend2)
			{
				thread2.resume();
				suspend2 = false;
			}
			else
			{
				thread2.suspend();
				output2.setText( "suspended" );
				suspend2 = true;
			}
		else if ( event.target == button3 )
			if ( suspend3)
			{
				thread3.resume();
				suspend3 = false;
			}
			else
			{
				thread3.suspend();
				output3.setText( "suspended" );
				suspend3 = true;
			}
		return true;
	}

		// execute the thread
	public void run()
	{
		int location;
		char display;
		String executingThread;

		while (true)
		{
		// sleep from 0 to 5 seconds
			try
			{	Thread.sleep( (int) (Math.random() * 5000) );	}
			catch ( InterruptedException exception )
			{	exception.printStackTrace(); }
			location = (int) (Math.random() * 26);
			display = alphabet.charAt (location);

			executingThread = Thread.currentThread().getName();

			if (executingThread.equals ( "Thread 1" ) )
				output1.setText ( "Thread 1: " + display );
			else if (executingThread.equals ( "Thread 2" ) )
				output2.setText ( "Thread 2: " + display );
			else if (executingThread.equals ( "Thread 3" ) )
				output3.setText ( "Thread 3: " + display );
		}
	}
}