HidePasswordFromCommandLine.java

import java.io.*;

  /**
  * Created on Feb 21, 2003
  */
  public class HidePasswordFromCommandLine extends Thread {
  boolean stopThread= false;
  boolean hideInput= false;
  boolean shortMomentGone= false;
  public void run() {
  try {
  sleep(500);
  } catch (InterruptedException e) {}
  shortMomentGone= true;
  while (!stopThread) {
  if (hideInput) {
  System.out.print("\b*");
  }
  try {
  sleep(1);
  } catch (InterruptedException e) {}
  }
  }
  public static void main(String[] arguments) {
  String name= "";
  String password= "";
  HidePasswordFromCommandLine hideThread= new HidePasswordFromCommandLine();
  hideThread.start();
  BufferedReader in= new BufferedReader(new InputStreamReader(System.in));
  try {
  System.out.println("Name: ");
  // Wait for the username and clear the keyboard buffer (if neccessarry)
  do {
  name= in.readLine();
  }
  while (hideThread.shortMomentGone == false);
  // Now the hide thread should begin to overwrite any input with "*"
  hideThread.hideInput= true;
  // Read the password
  System.out.println("\nPassword:");
  System.out.print(" ");
  password = in.readLine();
  hideThread.stopThread= true;
  }
  catch (Exception e) {}
  System.out.print("\b \b");
  // JUST FOR TESTING - PLEASE DELETE!
  System.out.println("\n\nLogin= " + name);
  System.out.println("Password= " + password);
  }
  }

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