1 package 驗證登錄信息是否合法;
 2 
 3 import java.util.Scanner;
 4 
 5 public class Login_Message_If_Legal {
 6     public static void main(String[] args) {
 7         Scanner input=new Scanner(System.in);
 8         boolean loop=true;
 9         while(loop){
10             System.out.println("Please enter your username:");
 
11             String Name=input.nextLine();
12             if(Name.equals("sa")){
13                 
14             }else{
15                 System.err.println("UserNaem is error,please again!");
16                 continue;
17             }
18             System.out.println("please your password:");
 
19             String password=input.nextLine();
20             if(password.equals("1314")){
21                 
22             }else{
23                 System.err.println("password is error,please again!");
24                 continue;
25             }    
26             loop=false;
27             System.out.println("login successful!");
 
28         }        
29     }
30 }

驗證登錄信息是否合法