public class Main {
    public static void main (String args[])throws Exception  {
        int n=20,result=0;
        try{
            result=n/0;
            System.out.println("结果为"+result);
        }
        catch(ArithmeticException ex){
            System.out.println("发算术异常: "+ex);
            try {
                throw new NumberFormatException();
            }
            catch(NumberFormatException ex1) {
                System.out.println("手动抛出链试异常 : "+ex1);
            }
        }
    }
}