@BeforeClass
public static void beforeClass() {
  APPLICATION_CONTEXT.registerBean("jettyReactiveWebServerFactory", JettyReactiveWebServerFactory.class, () -> new JettyReactiveWebServerFactory(0));
  APPLICATION_CONTEXT.registerBean("httpHandler", HttpHandler.class, () -> WebHttpHandlerBuilder.applicationContext(APPLICATION_CONTEXT).build());
  APPLICATION_CONTEXT.registerBean("webHandler", WebHandler.class, () -> SpringWebFluxTest::handler);
  APPLICATION_CONTEXT.refresh();

  final int serverPort = APPLICATION_CONTEXT.getWebServer().getPort();
  testRestTemplate = new TestRestTemplate(new RestTemplateBuilder().rootUri("http://127.0.0.1:" + serverPort));
}