参考文献 - moonseonhi/java-project GitHub Wiki
线程的调用 https://blog.csdn.net/jiesa/article/details/72845441 随机数 https://blog.csdn.net/qq_36868342/article/details/73478112 键盘监听器 https://www.cnblogs.com/KeenLeung/archive/2012/05/27/2520657.html class BallThread extends Thread线程的实现方法 https://www.cnblogs.com/kevinfuture/p/4281623.html 创建空白容器 Container pane=getContentPane(); https://blog.csdn.net/xuefeideren/article/details/41174677 如何实现画面可视化 https://blog.csdn.net/qq_34228570/article/details/72774088 改变组件位置setLocation(int x, int y): https://blog.csdn.net/u011235543/article/details/51892500/