SimpleRequestHandler { public final void start() { checkState(initialized, "handler has not been initialized"); checkState(!started, "container has already been started"); container.onStartup(); started = true; }  final void init(@Nonnull Application application); final void init(@Nonnull Application application, @Nullable Object parentManager); final void init(@Nonnull JRestlessHandlerContainer<JRestlessContainerRequest> handlerContainer); final void start(); final void stop(); final ResponseT delegateRequest(@Nonnull RequestT request);  }
@Test public void start_NotInitialized_ShouldThrowIse() { assertThrows(IllegalStateException.class, () -> new SimpleRequestHandlerImpl().start()); }