public boolean deliver(Receiver r)
public synchronized boolean deliver()
   public boolean deliver(Receiver r)   {      if (trace){ log.trace(r != null ? r + " requested delivery on " + this : "generic delivery requested on " + this); }            checkClosed();            try      {         return deliver(this, r);      }      catch (Throwable t)      {         log.error("Failed to deliver message", t);         return false;      }   }