Java05.java

import java.util.Scanner;

public class Java05 {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        String email = "";
        do {
            System.out.print("Input your e-mail: ");
            email = scan.nextLine().toLowerCase();
        } while (checkEmail(email));
        System.out.println("\nYour e-mail is "+email);

    }

    private static boolean checkEmail(String email){
        int searchAt = email.indexOf('@');
        if(searchAt != -1){
            //ตรวจสอบว่าลงท้ายด้วย hotmail.com, gmail.com หรือ  windowslive.com
            if(email.indexOf("hotmail.com") == searchAt+1){
                return false;
            }else if(email.indexOf("gmail.com") == searchAt+1){
                return false;
            }else if(email.indexOf("windowslive.com") == searchAt+1){
                return false;
            }
        }
        return true;
    }

}