// Drawing curve drawing

import javax.swing.*;
import java.awt.event.*;
import java.awt.*;

class Drawing extends JFrame {

    Drawing() {
	super( "Drawing" );
	getContentPane().add( new DrawingingPanel() );
        pack();
        setVisible(true);
    }

    class DrawingingPanel extends JPanel {

	static final int WIDTH = 500;
	static final int HEIGHT = 500;

	int x, y;
	int initialX, initialY;
	int initialMouseX, initialMouseY;

	DrawingingPanel( ) {
	    super();
	    setPreferredSize( new Dimension( WIDTH, HEIGHT ) );
	    x = 100;
	    y = 100;

	    addMouseListener( new MouseHandler() );
	    addMouseMotionListener( new MouseMotionHandler() );
	}

	protected void paintComponent(Graphics g) {
	    super.paintComponent(g);
	    g.drawRect( 0, 0, WIDTH-1, HEIGHT-1 );

	    g.setColor( Color.RED );
	    g.fillRect( 50, 150, 200, 200 );

	    g.setColor( Color.BLUE );
	    g.fillRect( 250, 150, 200, 200 );

	    g.setColor( new Color( 0.0f, 1.0f, 0.0f, 0.5f ) );
	    g.fillOval( x, y, 300, 300 );
	}

	class MouseHandler extends MouseAdapter {

	    public void mousePressed( MouseEvent e ) {
		initialMouseX = e.getX();
		initialMouseY = e.getY();
		initialX = x;
		initialY = y;

	    }
	}

	class MouseMotionHandler extends MouseMotionAdapter {

	    public void mouseDragged( MouseEvent e ) {
		int deltaX = e.getX() - initialMouseX;
		int deltaY = e.getY() - initialMouseY;
		
		x = initialX + deltaX;
		y = initialY + deltaY;

		repaint();
	    }
	}


    }

    public static void main( String [] args ) {
	Drawing h = new Drawing();
    }
}