import java.applet.Applet;
import java.util.Enumeration;
import java.awt.Graphics;
import java.awt.Dimension;
import java.awt.Event;
import java.awt.Color;

public class BabblerApplet
	extends Applet
	implements Runnable
	{
	/*
	An applet that writes a string directly into
	any sibling applet's window.
	*/

	private Thread thread;
	private String name;
	private Dimension size;
	private final static int SLEEP_TIME = 2000; //in milliseconds
	private final static int WINDOW_SIZE = 210; //in pixels
	private final static int OFFSET = 5; //in pixels

	public void init()
		{
		name = this.getParameter("BabblerName");
		this.resize(WINDOW_SIZE, WINDOW_SIZE);
		size = this.getSize();
		this.setBackground(Color.white);
		}

	public void start()
		{
		if (thread == null)
			{
			thread = new Thread(this);
			thread.start();
			}
		}

	public void stop()
		{
		thread = null;
		}

	public void run()
		{
		/*
		Repeatedly find all current siblings
		and write a string in their windows.
		*/

		while (thread != null)
			{
			Enumeration applets = this.getAppletContext().getApplets();
			while (applets.hasMoreElements())
				{
				Applet applet = (Applet) (applets.nextElement());
				String itsName = applet.getParameter("BabblerName");

				boolean isOther = (applet != this);
				boolean isSibling = (itsName != null);

				if (isOther && isSibling)
					{
					int place = 5 * OFFSET +
						(int) (Math.random() * (size.height - OFFSET));
					Graphics graphics = applet.getGraphics();
					graphics.drawString(name + " calling " + itsName, 0, place);
					}
				}

			try
				{
				Thread.sleep(SLEEP_TIME);
				}
			catch (InterruptedException exception)
				{
				System.out.println("interrupted");
				}
			}
		}

	public void paint(Graphics graphics)
		{
		graphics.drawRect(0, 0, size.width - OFFSET, size.height - OFFSET);
		graphics.drawString("Name: " + name, 0, 4 * OFFSET);
		}

	public boolean mouseDown(Event event, int x, int y)
		{
		/*
		Stop this applet if the user clicks in its window.
		*/

		stop();

		return false;
		}

	public boolean mouseEnter(Event event, int x, int y)
		{
		/*
		Clean this applet if the user moves over its window.
		*/

		repaint();

		return false;
		}
	}