说明：  Java烟花特效代码，用鼠标点击浏览器中的面板，将出现五彩缤纷的烟花效果。要用到的Java知识点有：鼠标事件的监听，Graphics类和Thread类的应用。使用Graphics类：绘制烟花，使用Thread类：管理线程，使用Math类：产生随机数，使用Color类：设置颜色。
(Fireworks effects Java code, use the mouse to click on the browser panel will appear colorful fireworks effects. To use the Java knowledge are: mouse event listener, Graphics class and the Thread class applications. Use the Graphics class: Draw fireworks, use the Thread class: Managing threads, use the Math class: generate random numbers, use the Color class: set the color.)