Source code: ExitThread/ExitThread.java

   package ExitThread;
   
   import java.io.*;
   
   public class ExitThread
   extends Thread
   {
     public void run()
     {
      try{
  
      BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
  
      while(true)
      {
        if(in.readLine().equals("quit")) System.exit(0);
      }
  
      } catch(Exception e) { System.out.println(e); }
    }
  }