package Chapter14Thread.bounce; import java.awt.geom.Ellipse2D; import java.awt.geom.Rectangle2D; import java.security.spec.EllipticCurve; public class Ball { private static final int XSIZE=15; private static final int YSIZE=15; private double x=0; private double y=0; private double dx=1; private double dy=1; public void move(Rectangle2D bounds){ x+=dx; y+=dy; if(x=bounds.getMaxX()){ x=bounds.getMaxX()-XSIZE; dx=-dx; } if(y=bounds.getMaxY()){ y=bounds.getMaxY()-YSIZE; dy=-dy; } } public Ellipse2D getShape(){ //ÔÚ£¨x,y£©´¦¹¹Ô쳤¿íΪXSIZEºÍYSIZEµÄÍÖÔ² return new Ellipse2D.Double(x, y, XSIZE, YSIZE); } }