/**
 * RubberLines.java 
 *
 * Demonstrates events, listeners and rubberbanding.
 * @author Lewis and Loftus.  Converted to JApplet by Scot Drysdale
 */
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class RubberLines extends JApplet implements MouseListener,
    MouseMotionListener {
	private static final long serialVersionUID = 1L;
	private final int APPLET_WIDTH = 500;
	private final int APPLET_HEIGHT = 500;
	private Point point1 = null;
	private Point point2 = null;

	/**
	 * Adds this class as a listener and does other initialization.
	 */
	public void init() {
		addMouseListener(this);
		addMouseMotionListener(this);

		setBackground(Color.black);
		setSize(APPLET_WIDTH, APPLET_HEIGHT);

		Container cp = getContentPane();    // Content pane holds components
		cp.add(new Canvas());               // The canvas is the only component

		setVisible(true);   // Makes the applet (and its components) visible
	}

	/**
	 * Captures the point where the mouse is pressed.
	 * @param event the event that caused this callback
	 */
	public void mousePressed(MouseEvent event) {
		point1 = event.getPoint();
	}

	/**
	 * Gets the current position of the mouse as it is dragged and
	 * draws the line to create the rubberband effect.
	 * 
	 * @param event the event that caused this callback
	 */
	public void mouseDragged(MouseEvent event) {
		point2 = event.getPoint();
		repaint();
	}

	//-----------------------------------------------------------------
	//  Provide empty definitions for unused event methods.
	//-----------------------------------------------------------------
	public void mouseClicked(MouseEvent event) {}
	public void mouseReleased(MouseEvent event) {}
	public void mouseEntered(MouseEvent event) {}
	public void mouseExited(MouseEvent event) {}
	public void mouseMoved(MouseEvent event) {}

	/**
	 * Serves as the drawing canvas for graphics.
	 */
	private class Canvas extends JPanel {
		private static final long serialVersionUID = 1L;

		/**
		 * Paints this component.
		 * @param page the Graphics object that we draw on.  
		 */
		public void paintComponent(Graphics page) {
			super.paintComponent(page);

			page.setColor(Color.red);
			if (point1 != null && point2 != null)
				page.drawLine(point1.x, point1.y, point2.x, point2.y);
		}
	}
}