class Check{

 public boolean validate(String name,

   String password){

  if(name.equals("lisifan")

    &&password.equals("mldn")){

   return true;

  }else{

   return false;

  }

 }

}

class Operate{

 private String info[];

 

 public Operate(String info[]){

  this.info=info;

 }

 public String login(){

  Check check=new Check();

  this.isExit();

  

  String name=this.info[0];

  String password=this.info[1];

  String str=null;

  if(check.validate(name, password)){

   str="欢迎"+name+"光临！";

  }else{

   str="错误的用户名和密码！";

  }

  return str;

 }

 public void isExit(){

  if(this.info.length!=2){

   System.out.println("输入的参数不正确，系统退出！");

   System.out.println("格式:java LoginDemo02 用户名 密码");

   System.exit(1);

  }

 }

}

public class LoginDemo02 {

 /**

  * @param args

  */

 public static void main(String[] args) {

  // TODO Auto-generated method stub

          Operate oper=new Operate(args);

          System.out.println(oper.login());

         

 }

}