protected void ensureStarted() {
        if (!isStarted()) {
            throw new LifeCycleException(String.format(
                "Component(%s) has not been started yet, please startup first!", getClass()
                    .getSimpleName()));
        }
    }
ensure the component has been startup before providing service.
src/main/java/com/alipay/remoting/AbstractLifeCycle.java