code: public void setServerCustomizers(
  			Collection<? extends JettyServerCustomizer> customizers) {
  		Assert.notNull(customizers, "Customizers must not be null");
  		this.jettyServerCustomizers = new ArrayList<>(customizers);
  	}
docs: Sets {@link JettyServerCustomizer}s that will be applied to the {@link Server}
  before it is started. Calling this method will replace any existing customizers.
  @param customizers the Jetty customizers to apply