本来是想实现泡泡屏保(javascript实现漂亮的气泡碰撞效果(Chrome浏览器下更佳) 下载-脚本之家)的，还未实现 

import javax.swing.*;
import java.awt.*;
import java.util.LinkedList;
import java.util.Random;class Bubble
{public static Image image;public int x;public int y;public int displayWidth;public int displayHeight;public int gravity;public double bounce;public Bubble(String image, int x, int y, int displayWidth, int displayHeight) {this.image = Toolkit.getDefaultToolkit().getImage("src//" + image);this.x = x;this.y = y;this.displayWidth = displayWidth;this.displayHeight = displayHeight;gravity = 1;bounce = 0.9;}public void move(){}@Overridepublic String toString() {return "Bubble{" +"x=" + x +", y=" + y +", displayWidth=" + displayWidth +", displayHeight=" + displayHeight +'}';}
}public class MainFrame extends JFrame implements Runnable {Graphics graphics;Image image;int x;int y;private final int windowWidth;//画板的宽度private final int windowHeight;//画板的高度private LinkedList<Bubble> bubbleLinkedList;private double ballsnum= 5;   // 小球数目private double spring= 0.8;   // 弹力加速度private double bounce= -0.95; // 反弹private double gravity= 0.1;  // 重力{setLayout(null);windowWidth = 629;windowHeight = 990;setSize(windowWidth, windowHeight);setLocationRelativeTo(null);setVisible(true);graphics = getContentPane().getGraphics();}MainFrame(){bubbleLinkedList = new LinkedList<>();for (int i = 0; i < 1; i++) {Integer x = new Random().nextInt(windowWidth / 10);Integer y = new Random().nextInt(windowHeight / 20);bubbleLinkedList.add(new Bubble("background.jpg", x, y, 20, 20));}}@Overridepublic void run() {while (true){for (Bubble b: bubbleLinkedList) {graphics.drawImage(b.image, b.x, b.y, b.displayWidth, b.displayHeight, this);BulletHit();b.move();}y+=10;try {Thread.sleep(100);} catch (InterruptedException e) {throw new RuntimeException(e);}}}public void move(Bubble bubble){gravity += 2;bubble.x += 2;bubble.y += gravity;System.out.println(bubble.x + ": " + bubble.y + ": " + bubble.displayHeight + ": " + windowHeight);if (bubble.y + bubble.displayHeight > windowHeight){bubble.y = windowHeight  - bubble.displayHeight;gravity *= -0.8;}}public void BulletHit(){for (Bubble bubble0: bubbleLinkedList){for (Bubble bubble1: bubbleLinkedList){if (!bubble0.equals(bubble1)){double x = Math.abs(bubble0.x - bubble1.x);double x0 = bubble0.x - bubble1.x;double y = Math.abs(bubble0.y - bubble1.y);double y0 = bubble0.y - bubble1.y;double dist = Math.sqrt(x * x + y * y);if (dist <= bubble0.displayWidth){double angle = Math.atan2(y0, x0);double tx = bubble0.x + Math.cos(angle) * dist;double ty = bubble0.y + Math.sin(angle) * dist;double ax = (tx - bubble1.x) * spring;double ay = (ty - bubble1.y) * spring;bubble0.x -= ax;bubble0.y -= ay;bubble1.x -= ax;bubble1.y -= ay;}}}}for (Bubble bubble0: bubbleLinkedList){move(bubble0);}}public static void main(String[] args) {MainFrame mainFrame = new MainFrame();new Thread(mainFrame).start();}
}