一个Java闹钟提醒小程序源代码，可以设置提醒周期、自定义提醒信息、在系统托盘显示图图标，主要都是Java基础类的知识，用到了AWT类库，Java新手朋友闲暇时参考一下。 -A Java alarm clock to remind applet source code, can be set to remind the cycle, a custom reminder message, shown in Figure icon in the system tray, are mainly t

编写一Java应用程序，计算圆的面积，当从键盘输入的半径不是double型数值时，产生异常提示：“您输入的不是数值，请从新输入”。（自行测试输入一字符（串）产生的结果-Write a Java application, calculate the area of the circle, when the input the keyboard is not the radius of the double type, it is a reminder: your input is not nu