很粗糙而且功能有限，是老师要求做的作业，呵呵！刚刚开始学习JAVA,菜鸟一名，请多指教,希望各位有经验的大哥大姐指导!-Very rough and limited functions, is the teacher asked to do work, huh, huh! Just started to learn JAVA, a rookie, please advice, I hope that Big Brother Big Sister experienced guide!