public class Clerk implements Runnable{
  private Bank theBank;   //the bank itself, ie the employer
  private Transaction inTray;   //to hold the transaction
//Constructor
  public Clerk(Bank theBank){
    this.theBank = theBank;
    inTray = null;
  }
  //Receive a teansaction
  public void doTransaction(Transaction transaction){ inTray = transaction;}
  //The clerk
  public void run(){
    while(true){
      while(inTray == null){   //No transaction waiting?
        try{ Thread.sleep(150); }
        catch(InterruptedException e){ System.out.println(e);}
      }//end of inner WHILE()
    theBank.doTransaction(inTray);
    inTray = null;  //inTray is empty
    }//end of outer WHILE()
    }//end of run()
  //Busy check
  public boolean isBusy(){return inTray != null;}
}//end of class Clerk