为啥后面的catch没反应?
package test9;
import java.util.;
public class WpjException4 {
public static double multi(int n)
{if(n<0) throw new IllegalArgumentException("输入了负数异常");
double s=1;
for(int i=1;i<=n;i++) s=si; return s ; }
public static void main(String[] args) {
Scanner bb=new Scanner(System.in);
try
{ int n=bb.nextInt();
System.out.println(n+"!="+multi(n));}
catch (ArrayIndexOutOfBoundsException e){ System.out.println("应该输入一个整数");}
catch (NumberFormatException e1)
{ System.out.println("应该输入一个数");}
catch (IllegalArgumentException e2)
{ System.out.println("出现的异常为:"+e2.toString());}
finally
{ System.out.println("计算阶乘结束");}
}
}