JAVASWING多线程产生随机球

package mypaint; import java.awt.Color; import java.awt.Graphics; import java.awt.Point; import java.awt.event.MouseEvent; import java.awt.event.MouseListener; import java.awt.event.WindowAdapter; import java.awt.event.WindowEvent; import java.util.Random; import javax.swing.JFrame; import javax.swing.JPanel; public class MyPaint { /** * @param 在鼠标点击处启动多线程，产生两个球，下落。 */ public static void main(String[] args) { // TODO Auto-generated method stub new MyFrame(); } } class MyFrame extends JFrame implements MouseListener { /** * */ private static final long serialVersionUID = 1L; Point p; JPanel jp; MyFrame() { super("画图"); jp = new JPanel(); jp.setBounds(0, 0, 800, 600); this.add(jp); this.jp.addMouseListener(this); // 设置窗体的位置和大小 this.setBounds(200, 50, 800, 600); this.setResizable(false); this.setVisible(true); this.addWindowListener(new WindowAdapter() { public void windowClosing(WindowEvent e) { System.exit(0); } }); } public void mouseClicked(MouseEvent e) { // TODO Auto-generated method stub p = e.getPoint(); Random r = new Random(); Ball ball = new Ball(p.x , p.y ); // Ball ball = new Ball(r.nextInt(600), 10); ball.start(); } public void mouseEntered(MouseEvent e) { // TODO Auto-generated method stub } public void mouseExited(MouseEvent e) { // TODO Auto-generated method stub } public void mousePressed(MouseEvent e) { // TODO Auto-generated method stub } public void mouseReleased(MouseEvent e) { // TODO Auto-generated method stub } class Ball extends Thread { int start_x, start_y; int ball_size = 30; Ball(int i, int j) { start_x = i-ball_size/2; start_y = j-ball_size/2; } public void run() { // TODO Auto-generated method stub // int n, m; // Graphics g = jp.getGraphics(); // Color c = jp.getBackground(); // for (int t = 0; t < 100;) { // n = start_x; // m = (int) (start_y + 6 * t); // g.setColor(Color.blue); // g.fillOval(n, m, 20, 20); // t++; // try { // Thread.sleep(50); // } catch (InterruptedException e) { // e.printStackTrace(); // } // g.setColor(c); // g.fillOval(n, m, 20, 20); // } Graphics g = jp.getGraphics(); // int x = 0, y = 0; // 计算画球时X轴,Y轴的最大坐标 int HuaBan_x = 800 - ball_size; int HuaBan_y = 570 - ball_size; // 球移动的增量 Random r1 = new Random(); Random r2 = new Random(); int x_increase = r1.nextInt(20)-10, y_increase = r2.nextInt(20)-10; while (true) { // 将上一次画的球擦掉 g.setColor(jp.getBackground()); g.fillOval(start_x, start_y, ball_size, ball_size); // 画球 g.setColor(Color.blue); start_x = start_x + x_increase; start_y = start_y + y_increase; g.fillOval(start_x, start_y, ball_size, ball_size); // 判断球是否到达了边界,若到达了则转向 if (start_x <= 0 || start_x >= HuaBan_x) x_increase = -x_increase; if (start_y <= 0 || start_y >= HuaBan_y) y_increase = -y_increase; try { // 休眠一段时间 Thread.sleep(30); } catch (Exception e) { } } } } }