java控制檯(不輸入,默認不輸入)

import java.util.Scanner; public class A { public A() { } public static void main (String[] args) { String username="jayqean"; String password="123"; System.out.println ("請輸入想修改的用戶名(不輸入默認不修改):"); Scanner sc=new Scanner(System.in); String name=sc.nextLine(); System.out.println ("請輸入想修改的密碼(不輸入默認不修改):"); String pwd=sc.nextLine(); username=name; password=pwd; System.out.println ("用戶名"+username+" 密碼"+password); } }