Fix media type regression in resource handling

Issue: SPR-14577

spring-web/src/main/java/org/springframework/web/accept/MappingMediaTypeFileExtensionResolver.java

@@ -67,6 +67,10 @@ public class MappingMediaTypeFileExtensionResolver implements MediaTypeFileExten
 	}
 
 
+	public Map<String, MediaType> getMediaTypes() {
+		return this.mediaTypes;
+	}
+
 	protected List<MediaType> getAllMediaTypes() {
 		return new ArrayList<>(this.mediaTypes.values());
 	}

spring-webmvc/src/main/java/org/springframework/web/servlet/resource/ResourceHttpRequestHandler.java

@@ -19,7 +19,9 @@ package org.springframework.web.servlet.resource;
 import java.io.IOException;
 import java.net.URLDecoder;
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 import javax.servlet.ServletContext;
 import javax.servlet.ServletException;
 import javax.servlet.ServletResponse;
@@ -51,6 +53,7 @@ import org.springframework.web.HttpRequestHandler;
 import org.springframework.web.accept.ContentNegotiationManager;
 import org.springframework.web.accept.ContentNegotiationManagerFactoryBean;
 import org.springframework.web.accept.PathExtensionContentNegotiationStrategy;
+import org.springframework.web.accept.ServletPathExtensionContentNegotiationStrategy;
 import org.springframework.web.context.request.ServletWebRequest;
 import org.springframework.web.cors.CorsConfiguration;
 import org.springframework.web.cors.CorsConfigurationSource;
@@ -111,7 +114,9 @@ public class ResourceHttpRequestHandler extends WebContentGenerator
 
 	private ContentNegotiationManager contentNegotiationManager;
 
-	private final ContentNegotiationManagerFactoryBean cnmFactoryBean = new ContentNegotiationManagerFactoryBean();
+	private ServletPathExtensionContentNegotiationStrategy pathExtensionStrategy;
+
+	private ServletContext servletContext;
 
 	private CorsConfiguration corsConfiguration;
 
@@ -254,7 +259,7 @@ public class ResourceHttpRequestHandler extends WebContentGenerator
 
 	@Override
 	protected void initServletContext(ServletContext servletContext) {
-		this.cnmFactoryBean.setServletContext(servletContext);
+		this.servletContext = servletContext;
 	}
 
 
@@ -268,16 +273,13 @@ public class ResourceHttpRequestHandler extends WebContentGenerator
 			this.resourceResolvers.add(new PathResourceResolver());
 		}
 		initAllowedLocations();
-		if (this.contentNegotiationManager == null) {
-			this.cnmFactoryBean.afterPropertiesSet();
-			this.contentNegotiationManager = this.cnmFactoryBean.getObject();
-		}
 		if (this.resourceHttpMessageConverter == null) {
 			this.resourceHttpMessageConverter = new ResourceHttpMessageConverter();
 		}
 		if (this.resourceRegionHttpMessageConverter == null) {
 			this.resourceRegionHttpMessageConverter = new ResourceRegionHttpMessageConverter();
 		}
+		this.pathExtensionStrategy = initPathExtensionStrategy();
 	}
 
 	/**
@@ -300,6 +302,19 @@ public class ResourceHttpRequestHandler extends WebContentGenerator
 		}
 	}
 
+	protected ServletPathExtensionContentNegotiationStrategy initPathExtensionStrategy() {
+		Map<String, MediaType> mediaTypes = null;
+		if (getContentNegotiationManager() != null) {
+			PathExtensionContentNegotiationStrategy strategy =
+					getContentNegotiationManager().getStrategy(PathExtensionContentNegotiationStrategy.class);
+			if (strategy != null) {
+				mediaTypes = new HashMap<>(strategy.getMediaTypes());
+			}
+		}
+		return new ServletPathExtensionContentNegotiationStrategy(this.servletContext, mediaTypes);
+	}
+
+
 	/**
 	 * Processes a resource request.
 	 * <p>Checks for the existence of the requested resource in the configured list of locations.
@@ -511,28 +526,7 @@ public class ResourceHttpRequestHandler extends WebContentGenerator
 	 * @return the corresponding media type, or {@code null} if none found
 	 */
 	protected MediaType getMediaType(HttpServletRequest request, Resource resource) {
-		MediaType mediaType = null;
+		return this.pathExtensionStrategy.getMediaTypeForResource(resource);
-
-		Class<PathExtensionContentNegotiationStrategy> clazz = PathExtensionContentNegotiationStrategy.class;
-		PathExtensionContentNegotiationStrategy strategy = this.contentNegotiationManager.getStrategy(clazz);
-		if (strategy != null) {
-			mediaType = strategy.getMediaTypeForResource(resource);
-		}
-
-		if (mediaType == null) {
-			ServletWebRequest webRequest = new ServletWebRequest(request);
-			try {
-				List<MediaType> mediaTypes = getContentNegotiationManager().resolveMediaTypes(webRequest);
-				if (!mediaTypes.isEmpty()) {
-					mediaType = mediaTypes.get(0);
-				}
-			}
-			catch (HttpMediaTypeNotAcceptableException ex) {
-				// Ignore
-			}
-		}
-
-		return mediaType;
 	}
 
 	/**

spring-webmvc/src/test/java/org/springframework/web/servlet/resource/ResourceHttpRequestHandlerTests.java

@@ -248,37 +248,38 @@ public class ResourceHttpRequestHandlerTests {
 		ContentNegotiationManager manager = factory.getObject();
 
 		List<Resource> paths = Collections.singletonList(new ClassPathResource("test/", getClass()));
-		this.handler = new ResourceHttpRequestHandler();
+		ResourceHttpRequestHandler handler = new ResourceHttpRequestHandler();
-		this.handler.setLocations(paths);
+		handler.setServletContext(new MockServletContext());
-		this.handler.setContentNegotiationManager(manager);
+		handler.setLocations(paths);
-		this.handler.afterPropertiesSet();
+		handler.setContentNegotiationManager(manager);
+		handler.afterPropertiesSet();
 
 		this.request.setAttribute(HandlerMapping.PATH_WITHIN_HANDLER_MAPPING_ATTRIBUTE, "foo.css");
-		this.handler.handleRequest(this.request, this.response);
+		handler.handleRequest(this.request, this.response);
 
 		assertEquals("foo/bar", this.response.getContentType());
 		assertEquals("h1 { color:red; }", this.response.getContentAsString());
 	}
 
-	@Test // SPR-13658
+	@Test // SPR-14577
-	public void getResourceWithRegisteredMediaTypeDefaultStrategy() throws Exception {
+	public void getMediaTypeWithFavorPathExtensionOff() throws Exception {
 		ContentNegotiationManagerFactoryBean factory = new ContentNegotiationManagerFactoryBean();
 		factory.setFavorPathExtension(false);
-		factory.setDefaultContentType(new MediaType("foo", "bar"));
 		factory.afterPropertiesSet();
 		ContentNegotiationManager manager = factory.getObject();
 
 		List<Resource> paths = Collections.singletonList(new ClassPathResource("test/", getClass()));
-		this.handler = new ResourceHttpRequestHandler();
+		ResourceHttpRequestHandler handler = new ResourceHttpRequestHandler();
-		this.handler.setLocations(paths);
+		handler.setServletContext(new MockServletContext());
-		this.handler.setContentNegotiationManager(manager);
+		handler.setLocations(paths);
-		this.handler.afterPropertiesSet();
+		handler.setContentNegotiationManager(manager);
+		handler.afterPropertiesSet();
 
-		this.request.setAttribute(HandlerMapping.PATH_WITHIN_HANDLER_MAPPING_ATTRIBUTE, "foo.css");
+		this.request.addHeader("Accept", "application/json,text/plain,*/*");
-		this.handler.handleRequest(this.request, this.response);
+		this.request.setAttribute(HandlerMapping.PATH_WITHIN_HANDLER_MAPPING_ATTRIBUTE, "foo.html");
+		handler.handleRequest(this.request, this.response);
 
-		assertEquals("foo/bar", this.response.getContentType());
+		assertEquals("text/html", this.response.getContentType());
-		assertEquals("h1 { color:red; }", this.response.getContentAsString());
 	}
 
 	@Test // SPR-14368
@@ -297,13 +298,13 @@ public class ResourceHttpRequestHandlerTests {
 		};
 
 		List<Resource> paths = Collections.singletonList(new ClassPathResource("test/", getClass()));
-		this.handler = new ResourceHttpRequestHandler();
+		ResourceHttpRequestHandler handler = new ResourceHttpRequestHandler();
-		this.handler.setServletContext(servletContext);
+		handler.setServletContext(servletContext);
-		this.handler.setLocations(paths);
+		handler.setLocations(paths);
-		this.handler.afterPropertiesSet();
+		handler.afterPropertiesSet();
 
 		this.request.setAttribute(HandlerMapping.PATH_WITHIN_HANDLER_MAPPING_ATTRIBUTE, "foo.css");
-		this.handler.handleRequest(this.request, this.response);
+		handler.handleRequest(this.request, this.response);
 
 		assertEquals("foo/bar", this.response.getContentType());
 		assertEquals("h1 { color:red; }", this.response.getContentAsString());
@@ -412,6 +413,7 @@ public class ResourceHttpRequestHandlerTests {
 
 		ResourceHttpRequestHandler handler = new ResourceHttpRequestHandler();
 		handler.setResourceResolvers(Collections.singletonList(pathResolver));
+		handler.setServletContext(new MockServletContext());
 		handler.setLocations(Arrays.asList(location1, location2));
 		handler.afterPropertiesSet();
 

spring-webmvc/src/test/java/org/springframework/web/servlet/resource/ResourceUrlProviderTests.java

@@ -58,6 +58,7 @@ public class ResourceUrlProviderTests {
 	public void setUp() throws Exception {
 		this.locations.add(new ClassPathResource("test/", getClass()));
 		this.locations.add(new ClassPathResource("testalternatepath/", getClass()));
+		this.handler.setServletContext(new MockServletContext());
 		this.handler.setLocations(locations);
 		this.handler.afterPropertiesSet();
 		this.handlerMap.put("/resources/**", this.handler);