自定义两个exception类，编写一段程序使用这两个类，从标准输入读入字符串，当字符串为空时抛出一个exception当字符串包含阿拉伯数字时抛出另一个exception 捕获exception-Two custom exception class, write a program using these two classes, read　the standard input string, the string is empty when thrown exception when a string of Arabic numerals throw another exception caught exception