1    package bookExamples.ch26Graphics.draw2d; 
2     
3     
4    import java.awt.*; 
5     
6    public class Arc2d extends Shape { 
7        private int x1 = 0; 
8        private int y1 = 0; 
9        private int w = 1; 
10       private int h = 1; 
11       private int xc = 0; 
12       private int yc = 0; 
13       private int startAngle = 90; 
14       private int arcAngle = 180; 
15       private Line2d plane = null; 
16    
17       public Arc2d(int _x1, int _y1, int _x2, int _y2) { 
18           x1 = _x1; 
19           y1 = _y1; 
20           w = Math.abs(_x2 - x1); 
21           h = Math.abs(_y2 - y1); 
22           int _x1PluswOn2 = _x1 + w / 2; 
23           plane = new Line2d(_x1PluswOn2, _y1, _x1PluswOn2, _y1 + h); 
24           xc = x1 + w / 2; 
25           yc = y1 + h / 2; 
26       } 
27    
28       public void paint(Graphics g) { 
29           g.drawArc(x1, y1, w, h, startAngle, arcAngle); 
30           plane.paint(g); 
31           g.fillOval(xc, yc, 2, 2); 
32           g.drawString("(" + xc + "," + yc + ")", xc + 3, yc + 3); 
33       } 
34   } 
35