用java随机画出两个圆，判断它们是否相交

 import java.awt.*;  
 import java.util.Random;  
 import javax.swing.*;  
 import javax.swing.border.TitledBorder;  
  
 /*** 
   7.  * 随机画出两个圆，判断它们是否相交 
   8.  * @author Firklaag 
   9.  * @ver 0.01 
  10.  * 编写代码实现同一平面内两圆是否碰撞，其中：第一个圆圆心坐标为(x1,y1)，
		半径是r1，第二个圆圆心坐标为(x2,y2)，
		半径是r2，数据结构自定义。 
  11.  */  
public class CheckCircul extends JFrame {  
    //定义画布  
    private MyPanel myPanel = new MyPanel();  
 
   public CheckCircul() {  
       add(myPanel);  
    }  
 
     public static void main(String[] args) {  
         CheckCircul demo = new CheckCircul();  
         run(demo, 800, 700);  
       }  
      /* 
     * 运行辅助方法 
        */  
    public static void run(final JFrame f, final int width, final int height) {  
       SwingUtilities.invokeLater(new Runnable() {  
            public void run() {  
                  f.setTitle(f.getClass().getSimpleName());  
                f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);  
                 f.setSize(width, height);  
                 f.setVisible(true);  
             }  
          });  
     }  
    
  }  
  /* 
  40.  * 画布类 
  41.  */  
 class MyPanel extends JPanel {  
     //定义标签  
     private JLabel label = new JLabel();  
     //定义随机数  
      private Random ran = new Random();  
    //定义两个圆  
     private Circul tom;  
     private Circul jerry;  
   
     /** 
  52.      * 生成两个圆并增加标签到画布 
  53.      */  
    public MyPanel() {  
        tom = new Circul(ran.nextInt(300), ran.nextInt(300), ran.nextInt(400));  
          jerry = new Circul(ran.nextInt(300), ran.nextInt(300), ran.nextInt(400));  
        this.setBorder(new TitledBorder("CheckCircul"));  
        add(label);  
     }  
  
    @Override  
    protected void paintComponent(Graphics g) {  
        //画出两个圆  
       Rectangle rec1 = tom.draw(g);  
        Rectangle rec2 = jerry.draw(g);  
        //判断其是否相交  
        if (rec1.intersects(rec2)) {  
             label.setText("相交");  
        } else {  
             label.setText("不相交");  
          }  
      }  
    
  }  
   /** 
  76.  * 定义圆形类，类中不仅有圆的属性，还有画圆的方法 
  77.  */  
  class Circul {  
      private int x;  
       private int y;  
      private int r;  
    
      public Circul(int x, int y, int r) {  
         this.x = x;  
        this.y = y;  
           this.r = r;  
      }  
   
      public Rectangle draw(Graphics g) {  
          Graphics2D g2d = (Graphics2D) g.create();  
          //调用抗锯齿API  
         g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING,  
                  RenderingHints.VALUE_ANTIALIAS_ON);  
         g2d.drawOval(x, y, r, r);  
          return new Rectangle(x, y, r, r);  
    
      }     
      public int getX() {  
         return x;  
      }  
   
     public void setX(int x) {  
         this.x = x;  
     }  
    
     public int getY() {  
         return y;  
     }  
   
      public void setY(int y) {  
          this.y = y;  
    }    
     public int getR() {  
          return r;  
     }  
   
     public void setR(int r) {  
         this.r = r;  
     }  
  }