Java中的main函數

1. package com.han;
3. public class HanTest {
4. public static void main(String[] args){
5. if(args==null){
6. throw new NullPointerException("The input is \"null\"");
7. }else if((args.length!=1&&args.length!=2)){
8. Throwable cause=new Throwable("You have to input 1 or 2 String arguments");
9. throw new IllegalArgumentException("Wrong numbers of args",cause);
10. //throw new IllegalArgumentException("Wrong numbers of args");
11. }else if(args.length==1){
12. System.out.println(args[0]);
13. }else if(args.length==2){
14. System.out.println(args[0]);
15. System.out.println(args[1]);
16. }
17. }
18. }

[java]

1. package com.han;
2. public class HanTest2 {
3. public static void main(String[] args){
4. String[] input={"han"};
5. //HanTest.main(null);
6. HanTest.main(input);
7. }
8. }