用递归求一个数的阶乘问题

 1 public class Demo {
 2 public static void main(String[] args) {
 3     Scanner sc = new Scanner(System.in);
 4     System.out.println("请输入一个数：");
 5     int i = sc.nextInt();
 6     System.out.println(i+"!为 "+getFac(i));
 7     sc.close();
 8 }
 9 
10 private static int getFac(int i) {
11     // TODO Auto-generated method stub
12     if (i<=0) {
13         return 0;
14     }else if (i==1) {
15         return 1;
16     }else {
17         return getFac(i-1)*i;
18     }
19 }
20 }