protected void performSendMessage(char id, int priority, Throwable throwable) {
      if (throwable != null) {
        PacketWriter packet = createPacket(id, priority);
        StringWriter stackTrace = new StringWriter();
        throwable.printStackTrace(new PrintWriter(stackTrace));
        packet.appendChar(EXCEPTION_CONTENT);
        packet.appendLimitedString(stackTrace.toString());
        send(packet);
      } else {
        performSendMessage(id, priority, "");
      }
    }
protected void performSendMessage(char id, int priority, Throwable throwable)