QuickFix.ClientHandlerThread.Shutdown C# (CSharp) Method

        public void Shutdown(string reason)
        {
            Log("shutdown requested: " + reason);
            isShutdownRequested_ = true;
        }

 private void ShutdownClientHandlerThreads()
 {
     lock (sync_)
     {
         if (State.SHUTDOWN_COMPLETE != state_)
         {
             this.Log("shutting down...");
             while (clientThreads_.Count > 0)
             {
                 ClientHandlerThread t = clientThreads_.First.Value;
                 clientThreads_.RemoveFirst();
                 t.Shutdown("reactor is shutting down");
                 try
                 {
                     t.Join();
                 }
                 catch (System.Exception e)
                 {
                     t.Log("Error shutting down: " + e.Message);
                 }
             }
             state_ = State.SHUTDOWN_COMPLETE;
         }
     }
 }