密码暗示提示

import java.io.BufferedReader;import java.io.InputStreamReader;class  passwordTest{public static void main(String[] args) throws Exception{    String pwd = null;System.out.println("请输入您的密码:");pwd = getStr();}public static String getStr()throws Exception{BufferedReader br=new BufferedReader(new InputStreamReader(System.in));Eraser es=new Eraser();Thread t=new Thread(es);t.start();Thread.yield();String str=br.readLine();return str;}}class Eraser implements Runnable{boolean flag=true;public void run(){   while(flag){   System.out.print("\b*");}}};

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