如何在Java中显示输入的星号？[副本]

Question

我需要在Java写一个小程序，要求一个人输入一个Pin码。所以我需要用星号(*)而不是数字隐藏Pin。我怎么能那样做？

到目前为止，这是我的代码：

import java.util.Scanner;
import java.io.*;


public class codePin {

    public static void main(String[] args){

        int pinSize = 0;

        do{
            Scanner pin = new Scanner(System.in);
            System.out.println("Enter Pin: ");
            int str = pin.nextInt();
            String s = new Integer(str).toString();

            pinSize = s.length();

            if(pinSize != 4){
            System.out.println("Your pin must be 4 integers");
            } else {
            System.out.println("We're checking if Pin was right...");
            }

        }while(pinSize != 4);
    }
}

实际上这个程序现在起作用，但我想增加一个功能，显示像“***”或“**”等的Pin。（当人员进入时，控制台中是自己的Pin）。我找到了可以完全隐藏别针的东西，但我不想这样。我要带星号的别针

有什么想法吗？谢谢

Answer 1

类似这样的事情：

import java.io.*;

public class Test {
    public static void main(final String[] args) {
        String password = PasswordField.readPassword("Enter password:");
        System.out.println("Password entered was:" + password);
    }
}


class PasswordField {

   public static String readPassword (String prompt) {
      EraserThread et = new EraserThread(prompt);
      Thread mask = new Thread(et);
      mask.start();

      BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
      String password = "";

      try {
          password = in.readLine();
      } catch (IOException ioe) {
          ioe.printStackTrace();
      }
      et.stopMasking();
      return password;
   }
}   

class EraserThread implements Runnable {
   private boolean stop;

   public EraserThread(String prompt) {
       System.out.print(prompt);
   }

   public void run () {
      while (!stop){
         System.out.print("\010*");
         try {
            Thread.currentThread().sleep(1);
         } catch(InterruptedException ie) {
            ie.printStackTrace();
         }
      }
   }

   public void stopMasking() {
      this.stop = true;
   }
}