import java.awt.*;
import java.applet.*;
import java.awt.event.*;    
import java.awt.geom.*;

public class DragAndDropApplet extends Applet implements MouseListener, MouseMotionListener
{
   //=============================================================================================
   // Data fields used in the program.
   //=============================================================================================
   
   public boolean dragging;
   public double squareX;
   public double squareY;

   //=============================================================================================
   // This method takes care of setting the listeners and initializes the datafields.
   //=============================================================================================
   
   public void init()
   {
      setBackground(Color.green);
      addMouseListener(this);          //listen for mouse events
      addMouseMotionListener(this);    //listen for mouse motion events
      
      squareX = 100;
      squareY = 100;
      dragging = false;
   }
 
   //=============================================================================================
   // This method simply paints the square at the squareX and squareY values.  These values are
   // updated in the mouseMoved method.
   //=============================================================================================
 
   public void paint(Graphics g) 
   {
      Graphics2D g2D = (Graphics2D)g;
      Rectangle2D.Double r = new Rectangle2D.Double(squareX-25, squareY-25, 50, 50);
      g2D.fill(r);      
   }

   //=============================================================================================
   // This method will relocate the center of the square if the square is currently being dragged.
   // It will then call the repaint method so that the square is actually painted at the new location.  
   //=============================================================================================
   
   public void mouseDragged(MouseEvent e)
   {
      if(dragging == true)
      {
         squareX = e.getX();  //set squareX to mouse's X
         squareY = e.getY();  //set squareY to mouse's Y
         repaint();
      }
   }
   
   //=============================================================================================
   // This method simply sets the 'dragging' variable to true if the click is on the square.
   //=============================================================================================
   
   public void mousePressed(MouseEvent e)
   {
      showStatus(e.getX() + "," + e.getY());
      if (e.getX() > squareX-25 && e.getX() < squareX+25 && e.getY() > squareY-25 && e.getY() < squareY+25) //if click is on square
      {
         dragging = true;
         showStatus("YES B" + e.getX() + "," + e.getY());
      }
   }

   //=============================================================================================
   // This method simply set the 'dragging' variable to false.   
   //=============================================================================================

   public void mouseReleased(MouseEvent e)
   {
         showStatus("released");
      dragging = false;
   }

   //=============================================================================================
   // The following are the interface (MouseListener and MouseMotionListener) methods that we will
   // not be using in this program.  
   //=============================================================================================

   public void mouseClicked(MouseEvent e)
   {
      //BLANK - NOT USED HERE
   }  
   
   public void mouseEntered(MouseEvent e)
   {
      //BLANK - NOT USED HERE 
   } 

   public void mouseExited (MouseEvent e)
   {      
      //BLANK - NOT USED HERE       
   } 
      
   public void mouseMoved(MouseEvent e)
   {
      //BLANK - NOT USED HERE   
   }

}