BAEL-944 Exploring the Spring MVC URL Matching Improvements (#1954)

* Example Code For Evaluation Article

This is an example code for the evaluation article on "Different Types of Bean Injection in Spring"

* Added unit tests

* Minor changes to application context

* Removed code committed for evaluation article

* BAEL-944 Demonstrating the problems with new Url pattern matching in Spring 5

* BAEL-944 Demonstrating the problems with new Url pattern matching in Spring 5

* BAEL-944 Exploring the Spring MVC URL Matching Improvements

* BAEL-944 Exploring the Spring MVC URL Matching Improvements

* BAEL-944 Exploring the Spring MVC URL Matching Improvements

* BAEL-944 Code Formatting and solving build issue

* BAEL-944 Resolving build issue due to change in Spring version

* BAEL-944 Resolving build issue

* BAEL-944 Formatting code

* BAEL-944 Moving tests to correct package

* BAEL-944 Moving tests to correct package

* BAEL-944 Replacing @RequestMapping by @GetMapping

* BAEL-944 Remove unnecessary attribute name, "value" in annotations

spring-5/src/main/java/com/baeldung/Spring5Application.java

@@ -2,8 +2,10 @@ package com.baeldung;
 
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.annotation.ComponentScan;
 
 @SpringBootApplication
+@ComponentScan(basePackages = {"com.baeldung.web"})
 public class Spring5Application {
 
     public static void main(String[] args) {

spring-5/src/main/java/com/baeldung/functional/ExploreSpring5URLPatternUsingRouterFunctions.java

@@ -0,0 +1,61 @@
+package com.baeldung.functional;
+
+import static org.springframework.web.reactive.function.BodyInserters.fromObject;
+import static org.springframework.web.reactive.function.server.RequestPredicates.GET;
+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;
+
+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;
+
+public class ExploreSpring5URLPatternUsingRouterFunctions {
+
+    private RouterFunction<ServerResponse> routingFunction() {
+
+        return route(GET("/p?ths"), serverRequest -> ok().body(fromObject("/p?ths"))).andRoute(GET("/test/{*id}"), serverRequest -> ok().body(fromObject(serverRequest.pathVariable("id"))))
+            .andRoute(GET("/*card"), serverRequest -> ok().body(fromObject("/*card path was accessed")))
+            .andRoute(GET("/{var1}_{var2}"), serverRequest -> ok().body(fromObject(serverRequest.pathVariable("var1") + " , " + serverRequest.pathVariable("var2"))))
+            .andRoute(GET("/{baeldung:[a-z]+}"), serverRequest -> ok().body(fromObject("/{baeldung:[a-z]+} was accessed and baeldung=" + serverRequest.pathVariable("baeldung"))))
+            .and(RouterFunctions.resources("/files/{*filepaths}", new ClassPathResource("files/")));
+    }
+
+    WebServer start() throws Exception {
+        WebHandler 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();
+        }
+    }
+
+}

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

@@ -15,6 +15,7 @@ import org.springframework.security.config.annotation.web.configuration.WebSecur
 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;
 
@@ -58,7 +59,7 @@ public class FunctionalSpringBootApplication {
     @Bean
     public ServletRegistrationBean servletRegistrationBean() throws Exception {
         HttpHandler httpHandler = WebHttpHandlerBuilder
-          .webHandler(toHttpHandler(routingFunction()))
+          .webHandler((WebHandler) toHttpHandler(routingFunction()))
           .prependFilter(new IndexRewriteFilter())
           .build();
         ServletRegistrationBean registrationBean = new ServletRegistrationBean<>(new RootServlet(httpHandler), "/");

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

@@ -50,7 +50,7 @@ public class FunctionalWebApplication {
     }
 
     WebServer start() throws Exception {
-        WebHandler webHandler = toHttpHandler(routingFunction());
+        WebHandler webHandler = (WebHandler) toHttpHandler(routingFunction());
         HttpHandler httpHandler = WebHttpHandlerBuilder
           .webHandler(webHandler)
           .prependFilter(new IndexRewriteFilter())

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

@@ -19,7 +19,7 @@ class IndexRewriteFilter implements WebFilter {
               .mutate()
               .request(builder -> builder
                 .method(request.getMethod())
-                .contextPath(request.getContextPath())
+                .contextPath(request.getPath().toString())
                 .path("/test"))
               .build());
         }

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

@@ -23,12 +23,13 @@ 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;
+import org.springframework.web.server.WebHandler;
 
 public class RootServlet extends ServletHttpHandlerAdapter {
 
     public RootServlet() {
         this(WebHttpHandlerBuilder
-          .webHandler(toHttpHandler(routingFunction()))
+          .webHandler((WebHandler) toHttpHandler(routingFunction()))
           .prependFilter(new IndexRewriteFilter())
           .build());
     }

spring-5/src/main/java/com/baeldung/web/PathPatternController.java

@@ -0,0 +1,40 @@
+package com.baeldung.web;
+
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+public class PathPatternController {
+
+    @GetMapping("/spring5/{*id}")
+    public String URIVariableHandler(@PathVariable String id) {
+        return id;
+    }
+
+    @GetMapping("/s?ring5")
+    public String wildcardTakingExactlyOneChar() {
+        return "/s?ring5";
+    }
+
+    @GetMapping("/spring5/*id")
+    public String wildcardTakingZeroOrMoreChar() {
+        return "/spring5/*id";
+    }
+
+    @GetMapping("/resources/**")
+    public String wildcardTakingZeroOrMorePathSegments() {
+        return "/resources/**";
+    }
+
+    @GetMapping("/{baeldung:[a-z]+}")
+    public String regexInPathVariable(@PathVariable String baeldung) {
+        return baeldung;
+    }
+
+    @GetMapping("/{var1}_{var2}")
+    public String multiplePathVariablesInSameSegment(@PathVariable String var1, @PathVariable String var2) {
+        return "Two variables are var1=" + var1 + " and var2=" + var2;
+    }
+}