import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
    
    
public class Draw extends JApplet implements KeyListener
{  
	Display canvas;
	
	public void init()
	{
		canvas = new Display();
		setContentPane(canvas);
	}
	   
	public char mode = 'c';
	   
	public void keyTyped(KeyEvent evt) 
	{
		char ch = evt.getKeyChar();
		
		if (ch == 'p' || ch == 'P')
			mode = 'p';
		else if (ch == 'c' || ch == 'C')
			mode = 'c';
		else if (ch == 'b' || ch == 'B')
			mode = 'b';
	}
	   
	public void keyPressed(KeyEvent evt) {}
	public void keyReleased(KeyEvent evt) {}
	
    class Display extends JPanel implements MouseListener
	{
            
          /* Variables for implementing polygon input. */

		private int[] xCoord, yCoord;  // Arrays containing the points of 
                                         //   the polygon.  Up to 500 points 
                                         //   are allowed.

		private int pointCt;  // The number of points that have been input.

		private Color polygonColor = Color.red;
                               // Color that is used to draw the polygons. 
		  
		private Color theColor = Color.red;
		

		public Display() 
		{
			setBackground(Color.white);
			addMouseListener(this);
			xCoord = new int[500];
			yCoord = new int[500];
			pointCt = 0;
		}


		public void paintComponent(Graphics g) 
		{

			super.paintComponent(g); // Fills with background color, white.
			g.setColor(Color.black);
			g.drawRect(0, 0, getWidth() - 1, getHeight() - 1);
			g.drawRect(1, 1, getWidth() - 3, getHeight() - 3);
			g.drawLine(35, 0, 35, 250);
			 
			g.setColor(Color.black);
			g.fillRect(0, 0, 35, 50);
			
			g.setColor(Color.blue);
			g.fillRect(0, 50, 35, 100);
			 
			g.setColor(Color.red);
			g.fillRect(0, 100, 35, 150);
			 
			g.setColor(Color.yellow);
			g.fillRect(0, 150, 35, 200);
			
			g.setColor(Color.green);
			g.fillRect(0, 200, 35, 250);
		}


		private void putLine(int x1, int y1, int x2, int y2) 
		{
			Graphics g = getGraphics();
			g.drawLine(x1,y1,x2,y2);
			g.dispose();
		}
		  
		private void drawACircle (int x1, int y1, int x2, int y2)
		{
			Graphics g = getGraphics();
			int dx, dy;
			
			dx = Math.abs(x1 - x2);
			dy = Math.abs(y1 - y2);
			double radius = Math.sqrt((dx * dx) + (dy * dy));
		
			g.setColor(theColor);
			g.fillOval(x1, y1, (int)radius, (int)radius);
			g.dispose();
		}


		private void putPolygon()
		{
			if (pointCt < 2)
				return;
			Graphics g = getGraphics();
			if (pointCt == 2) 
			{
				g.drawLine(xCoord[0], yCoord[0], xCoord[1], yCoord[1]);
			}
			else 
			{
				g.setColor(theColor);
				g.fillPolygon(xCoord, yCoord, pointCt);
				g.setColor(Color.black);
				g.drawPolygon(xCoord, yCoord, pointCt);
			}
				g.dispose();
		}


		public void mousePressed(MouseEvent evt) 
		{ 
			if (evt.isShiftDown()) 
			{
				pointCt = 0;
				repaint();
			}
			else if ( pointCt > 0 && (Math.abs(xCoord[0] - evt.getX())<=2) && (Math.abs(yCoord[0] - evt.getY())<=2) && mode == 'p' ) 
			{
				putPolygon();
				pointCt = 0;
			}
			else if (evt.isMetaDown() || pointCt == 500)
			{
				putPolygon();
				pointCt = 0;
			}
			else 
			{
				if (mode == 'p') 
				{
				
					xCoord[pointCt] = evt.getX();
					yCoord[pointCt] = evt.getY();
						//Get color to be used
					if (evt.getX() <= 25) 
					{
						if (evt.getY() <= 50)
							theColor = Color.black;
						else if (evt.getY() <= 100)
							theColor = Color.blue;
						else if (evt.getY() <= 150)
							theColor = Color.red;
						else if (evt.getY() <= 200)
							theColor = Color.yellow;
						else if (evt.getY() <= 250)
							theColor = Color.green;
				
							pointCt--;
					} 
				
					pointCt++;
				
					if (pointCt >= 2 && evt.getX() > 25) 
					{
						putLine(xCoord[pointCt-2], yCoord[pointCt-2], xCoord[pointCt-1], yCoord[pointCt-1]); 
					}
				}// end if 'p'
		 
				if (mode == 'c') //Circle Mode
				{
					xCoord[pointCt] = evt.getX();
					yCoord[pointCt] = evt.getY();
				
					if (evt.getX() <= 25)
					{
							if (evt.getY() <= 50)
								theColor = Color.black;
							else if (evt.getY() <= 100)
								theColor = Color.blue;
							else if (evt.getY() <= 150)
								theColor = Color.red;
							else if (evt.getY() <= 200)
								theColor = Color.yellow;
							else if (evt.getY() <= 250)
								theColor = Color.green;
					}
					
					pointCt++;
				
					if (pointCt >= 2 && evt.getX() > 25) 
					{
						drawACircle(xCoord[pointCt-1], yCoord[pointCt-1], xCoord[pointCt], yCoord[pointCt]); 
						pointCt = 0;
					}
				}//end mode 'c'
			} //end else
			canvas.requestFocus();
		} // end mousePressed()

		public void mouseReleased(MouseEvent evt) { }
		public void mouseClicked(MouseEvent evt) { }
		public void mouseEntered(MouseEvent evt) { }
		public void mouseExited(MouseEvent evt) { }
          
	} // end nested class Display
}  // end class Draw

<html>
<head>
<TITLE>Simple Paint Program</TITLE>
</head>
<body>

<p align=center>
<applet code="Draw.class" height=250 width=300>
</applet>
</p>

</body>
</html>