anchor.diff:  Generally, you can follow the advice from
   "`<<howto-discover-build-in-options-for-external-properties>>`" about
   `@ConfigurationProperties` (`ServerProperties` is the main one here). However, you should
  -also look at `ServletWebServerFactoryCustomizer` and various Tomcat-specific
  +also look at `WebServerFactoryCustomizer` and various Tomcat-specific
   `+*Customizers+` that you can add. The Tomcat APIs are quite rich. Consequently, once you
   have access to the `TomcatServletWebServerFactory`, you can modify it in a number of ways.
   Alternatively, if you need more control and customization, you can add your own
  
positive.code: [[howto-discover-the-http-port-at-runtime]]
  === Discover the HTTP Port at Runtime
  You can access the port the server is running on from log output or from the
  `ServletWebServerApplicationContext` through its `EmbeddedWebServer`. The best way to get
  that and be sure that it has been initialized is to add a `@Bean` of type
  `ApplicationListener<ServletWebServerInitializedEvent>` and pull the container
  out of the event when it is published.
  
  
negative.code: [source,java,indent=0,subs="verbatim,quotes,attributes"]
  ----
  	import org.springframework.boot.autoconfigure.SpringBootApplication;
  	import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;
  	import org.springframework.web.WebApplicationInitializer;
  
  	@SpringBootApplication
  