java 賬號註冊(length(),equals())

package com.zc.homeWork06;

import java.util.Scanner;

//賬號註冊，用戶名不小於3位，密碼不小於6位
public class Register {

    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        // 賬號註冊
        System.out.println("賬號註冊");
        //String i = input.next();
        for(int i=0;;i++) {
            System.out.print("請輸入註冊賬號（不小於3位數）：");
            String username = input.next();

            // 驗證賬號長度是否正確
            if (username.length() < 3) {
                System.out.println("輸入的賬號不得少於3位數，請重新註冊！\n");
                continue;
            }
            System.out.print("請輸入密碼（不小於6位數）：");
            String password = input.next();

            // 驗證密碼長度是否正確
            if (password.length() < 6) {
                System.out.println("輸入的密碼不得少於6位數，請重新註冊！\n");
                continue;
            }
            System.out.print("再次輸入密碼：");
            String passwordagain = input.next();

            // 驗證兩次密碼是否一致
            if (!passwordagain.equals(password)) {
                System.out.println("兩次密碼輸入不一致，請重新註冊！\n");
                continue;
            }
            System.out.println("註冊成功！！！\n");
            System.out.println("用戶名\t密碼");
            System.out.println(username + "\t" + password);
            break;
        }

    }

}