//
// FILE:     Disk.java
// AUTHOR:   Eugene Wallingford 
// DATE:     2012/09/18
// COMMENT:  extracted from Ball class by Tim Budd in the textbook
//           Understanding Object-Oriented Programming with Java
//
// MODIFIED: 2012/10/02 -- Eugene Wallingford
// CHANGE:   added x() and y() accessors for subclass use
//
// MODIFIED: 2012/10/11 -- Eugene Wallingford
// CHANGE:   added darker() and brighter() methods for subclass use
//

import java.awt.Color;
import java.awt.Graphics;

public class Disk
{
  
  private int   x;
  private int   y;
  private int   radius;
  private Color color;

  public Disk( int x, int y, int r )
  {
    this.x = x;
    this.y = y;
    radius = r;
    color  = Color.blue;
  }

  public void paint( Graphics g )
  {
    g.setColor( color );
    g.fillOval( x, y, radius*2, radius*2 );
  }
  
  protected void moveBy( int deltaX, int deltaY )
  {
    x += deltaX;
    y += deltaY;
  }
  
  protected int x() { return x; }
  protected int y() { return y; }
  
  protected void darker()
  {
    color = color.darker();
  }
  
  protected void brighter()
  {
    color = color.brighter();
  }
  
  // accessors for subclasses
  
  protected void become( Color newColor )
  {
    color = newColor;
  }
}