#BAEL-636 (#1468)

* jira #BAEL-636

* remove redundant dependency spring-boot-starter-reactive

spring-5/src/main/java/com/baeldung/functional/FunctionalWebApplication.java

@@ -0,0 +1,80 @@
+package com.baeldung.functional;
+
+import org.apache.catalina.Context;
+import org.apache.catalina.startup.Tomcat;
+import org.springframework.boot.web.embedded.tomcat.TomcatWebServer;
+import org.springframework.boot.web.server.WebServer;
+import org.springframework.core.io.ClassPathResource;
+import org.springframework.http.server.reactive.HttpHandler;
+import org.springframework.http.server.reactive.ServletHttpHandlerAdapter;
+import org.springframework.web.reactive.function.server.RouterFunction;
+import org.springframework.web.reactive.function.server.RouterFunctions;
+import org.springframework.web.reactive.function.server.ServerResponse;
+import org.springframework.web.server.WebHandler;
+import org.springframework.web.server.adapter.WebHttpHandlerBuilder;
+import reactor.core.publisher.Flux;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.concurrent.CopyOnWriteArrayList;
+
+import static org.springframework.web.reactive.function.BodyInserters.fromObject;
+import static org.springframework.web.reactive.function.server.RequestPredicates.*;
+import static org.springframework.web.reactive.function.server.RouterFunctions.route;
+import static org.springframework.web.reactive.function.server.RouterFunctions.toHttpHandler;
+import static org.springframework.web.reactive.function.server.ServerResponse.ok;
+
+public class FunctionalWebApplication {
+
+    private static final Actor BRAD_PITT = new Actor("Brad", "Pitt");
+    private static final Actor TOM_HANKS = new Actor("Tom", "Hanks");
+    private static final List<Actor> actors = new CopyOnWriteArrayList<>(Arrays.asList(BRAD_PITT, TOM_HANKS));
+
+    private RouterFunction<ServerResponse> routingFunction() {
+        FormHandler formHandler = new FormHandler();
+
+        RouterFunction<ServerResponse> restfulRouter = route(GET("/"), serverRequest -> ok().body(Flux.fromIterable(actors), Actor.class)).andRoute(POST("/"), serverRequest -> serverRequest
+          .bodyToMono(Actor.class)
+          .doOnNext(actors::add)
+          .then(ok().build()));
+
+        return route(GET("/test"), serverRequest -> ok().body(fromObject("helloworld")))
+          .andRoute(POST("/login"), formHandler::handleLogin)
+          .andRoute(POST("/upload"), formHandler::handleUpload)
+          .and(RouterFunctions.resources("/files/**", new ClassPathResource("files/")))
+          .andNest(path("/actor"), restfulRouter)
+          .filter((request, next) -> {
+              System.out.println("Before handler invocation: " + request.path());
+              return next.handle(request);
+          });
+    }
+
+    WebServer start() throws Exception {
+        WebHandler webHandler = toHttpHandler(routingFunction());
+        HttpHandler httpHandler = WebHttpHandlerBuilder
+          .webHandler(webHandler)
+          .prependFilter(new IndexRewriteFilter())
+          .build();
+
+        Tomcat tomcat = new Tomcat();
+        tomcat.setHostname("localhost");
+        tomcat.setPort(9090);
+        Context rootContext = tomcat.addContext("", System.getProperty("java.io.tmpdir"));
+        ServletHttpHandlerAdapter servlet = new ServletHttpHandlerAdapter(httpHandler);
+        Tomcat.addServlet(rootContext, "httpHandlerServlet", servlet);
+        rootContext.addServletMappingDecoded("/", "httpHandlerServlet");
+
+        TomcatWebServer server = new TomcatWebServer(tomcat);
+        server.start();
+        return server;
+
+    }
+
+    public static void main(String[] args) {
+        try {
+            new FunctionalWebApplication().start();
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+}