diff --git a/spring-test/src/main/java/org/springframework/mock/web/MockServletContext.java b/spring-test/src/main/java/org/springframework/mock/web/MockServletContext.java
index cd5b8d8769..e7b0b7737f 100644
--- a/spring-test/src/main/java/org/springframework/mock/web/MockServletContext.java
+++ b/spring-test/src/main/java/org/springframework/mock/web/MockServletContext.java
@@ -263,14 +263,12 @@ public class MockServletContext implements ServletContext {
 	@Override
 	public String getMimeType(String filePath) {
 		String extension = StringUtils.getFilenameExtension(filePath);
-		MediaType result;
 		if (this.mimeTypes.containsKey(extension)) {
-			result = this.mimeTypes.get(extension);
+			return this.mimeTypes.get(extension).toString();
 		}
 		else {
-			result = MediaTypeFactory.getMediaType(filePath);
+			return MediaTypeFactory.getMediaType(filePath).orElse(MediaType.APPLICATION_OCTET_STREAM).toString();
 		}
-		return result != null ? result.toString() : null;
 	}
 
 	/**
diff --git a/spring-web/src/main/java/org/springframework/http/MediaTypeFactory.java b/spring-web/src/main/java/org/springframework/http/MediaTypeFactory.java
index 078ddfce4e..5dfe8c6aa2 100644
--- a/spring-web/src/main/java/org/springframework/http/MediaTypeFactory.java
+++ b/spring-web/src/main/java/org/springframework/http/MediaTypeFactory.java
@@ -103,9 +103,12 @@ public class MediaTypeFactory {
 	 * @param resource the resource to introspect
 	 * @return the corresponding media type, or {@code null} if none found
 	 */
-	public static MediaType getMediaType(Resource resource) {
+	public static Optional<MediaType> getMediaType(Resource resource) {
+		if (resource == null) {
+			return Optional.empty();
+		}
 		String filename = resource.getFilename();
-		return (filename != null ? getMediaType(filename) : null);
+		return (filename != null ? getMediaType(filename) : Optional.empty());
 	}
 
 	/**
@@ -113,9 +116,9 @@ public class MediaTypeFactory {
 	 * @param filename the file name plus extension
 	 * @return the corresponding media type, or {@code null} if none found
 	 */
-	public static MediaType getMediaType(String filename) {
+	public static Optional<MediaType> getMediaType(String filename) {
 		List<MediaType> mediaTypes = getMediaTypes(filename);
-		return (!mediaTypes.isEmpty() ? mediaTypes.get(0) : null);
+		return (!mediaTypes.isEmpty() ? Optional.of(mediaTypes.get(0)) : Optional.empty());
 	}
 
 	/**
diff --git a/spring-web/src/main/java/org/springframework/http/codec/ResourceHttpMessageWriter.java b/spring-web/src/main/java/org/springframework/http/codec/ResourceHttpMessageWriter.java
index 3765d7ecc4..d074e9d234 100644
--- a/spring-web/src/main/java/org/springframework/http/codec/ResourceHttpMessageWriter.java
+++ b/spring-web/src/main/java/org/springframework/http/codec/ResourceHttpMessageWriter.java
@@ -136,8 +136,7 @@ public class ResourceHttpMessageWriter implements ServerHttpMessageWriter<Resour
 		if (type != null && type.isConcrete() && !type.equals(MediaType.APPLICATION_OCTET_STREAM)) {
 			return type;
 		}
-		type = MediaTypeFactory.getMediaType(resource);
-		return type != null ? type : MediaType.APPLICATION_OCTET_STREAM;
+		return MediaTypeFactory.getMediaType(resource).orElse(MediaType.APPLICATION_OCTET_STREAM);
 	}
 
 	private static OptionalLong lengthOf(Resource resource) {
diff --git a/spring-web/src/main/java/org/springframework/http/converter/ResourceHttpMessageConverter.java b/spring-web/src/main/java/org/springframework/http/converter/ResourceHttpMessageConverter.java
index 9c5c1245f3..321b29a532 100644
--- a/spring-web/src/main/java/org/springframework/http/converter/ResourceHttpMessageConverter.java
+++ b/spring-web/src/main/java/org/springframework/http/converter/ResourceHttpMessageConverter.java
@@ -102,8 +102,7 @@ public class ResourceHttpMessageConverter extends AbstractHttpMessageConverter<R
 
 	@Override
 	protected MediaType getDefaultContentType(Resource resource) {
-		MediaType mediaType = MediaTypeFactory.getMediaType(resource);
-		return mediaType != null ? mediaType : MediaType.APPLICATION_OCTET_STREAM;
+		return MediaTypeFactory.getMediaType(resource).orElse(MediaType.APPLICATION_OCTET_STREAM);
 	}
 
 	@Override
diff --git a/spring-web/src/main/java/org/springframework/http/converter/ResourceRegionHttpMessageConverter.java b/spring-web/src/main/java/org/springframework/http/converter/ResourceRegionHttpMessageConverter.java
index 17292ee85e..4e76c2a8ca 100644
--- a/spring-web/src/main/java/org/springframework/http/converter/ResourceRegionHttpMessageConverter.java
+++ b/spring-web/src/main/java/org/springframework/http/converter/ResourceRegionHttpMessageConverter.java
@@ -87,14 +87,7 @@ public class ResourceRegionHttpMessageConverter extends AbstractGenericHttpMessa
 				resource = regions.iterator().next().getResource();
 			}
 		}
-		MediaType result = null;
-		if (resource != null) {
-			result = MediaTypeFactory.getMediaType(resource);
-		}
-		if (result == null) {
-			return MediaType.APPLICATION_OCTET_STREAM;
-		}
-		return result;
+		return MediaTypeFactory.getMediaType(resource).orElse(MediaType.APPLICATION_OCTET_STREAM);
 	}
 
 	@Override
diff --git a/spring-web/src/main/java/org/springframework/web/accept/PathExtensionContentNegotiationStrategy.java b/spring-web/src/main/java/org/springframework/web/accept/PathExtensionContentNegotiationStrategy.java
index d26704c655..2795db7447 100644
--- a/spring-web/src/main/java/org/springframework/web/accept/PathExtensionContentNegotiationStrategy.java
+++ b/spring-web/src/main/java/org/springframework/web/accept/PathExtensionContentNegotiationStrategy.java
@@ -18,6 +18,7 @@ package org.springframework.web.accept;
 
 import java.util.Locale;
 import java.util.Map;
+import java.util.Optional;
 import javax.servlet.http.HttpServletRequest;
 
 import org.apache.commons.logging.Log;
@@ -112,9 +113,9 @@ public class PathExtensionContentNegotiationStrategy extends AbstractMappingCont
 	protected MediaType handleNoMatch(NativeWebRequest webRequest, String extension)
 			throws HttpMediaTypeNotAcceptableException {
 
-		MediaType mediaType = MediaTypeFactory.getMediaType("file." + extension);
-		if (mediaType != null) {
-			return mediaType;
+		Optional<MediaType> mediaType = MediaTypeFactory.getMediaType("file." + extension);
+		if (mediaType.isPresent()) {
+			return mediaType.get();
 		}
 		if (this.ignoreUnknownExtensions) {
 			return null;
@@ -140,7 +141,7 @@ public class PathExtensionContentNegotiationStrategy extends AbstractMappingCont
 			mediaType = lookupMediaType(extension);
 		}
 		if (mediaType == null) {
-			mediaType = MediaTypeFactory.getMediaType(filename);
+			mediaType = MediaTypeFactory.getMediaType(filename).orElse(null);
 		}
 		return mediaType;
 	}
diff --git a/spring-web/src/test/java/org/springframework/http/MediaTypeFactoryTests.java b/spring-web/src/test/java/org/springframework/http/MediaTypeFactoryTests.java
index 9f547c5191..3ae5a1f8f8 100644
--- a/spring-web/src/test/java/org/springframework/http/MediaTypeFactoryTests.java
+++ b/spring-web/src/test/java/org/springframework/http/MediaTypeFactoryTests.java
@@ -18,7 +18,9 @@ package org.springframework.http;
 
 import org.junit.Test;
 
-import static org.junit.Assert.assertEquals;
+import org.springframework.core.io.Resource;
+
+import static org.junit.Assert.*;
 
 /**
  * @author Arjen Poutsma
@@ -27,9 +29,17 @@ public class MediaTypeFactoryTests {
 
 	@Test
 	public void getMediaType() {
-		assertEquals(MediaType.APPLICATION_XML, MediaTypeFactory.getMediaType("file.xml"));
-		assertEquals(MediaType.parseMediaType("application/javascript"), MediaTypeFactory.getMediaType("file.js"));
-		assertEquals(MediaType.parseMediaType("text/css"), MediaTypeFactory.getMediaType("file.css"));
+		assertEquals(MediaType.APPLICATION_XML, MediaTypeFactory.getMediaType("file.xml").get());
+		assertEquals(MediaType.parseMediaType("application/javascript"), MediaTypeFactory.getMediaType("file.js").get());
+		assertEquals(MediaType.parseMediaType("text/css"), MediaTypeFactory.getMediaType("file.css").get());
+		assertFalse(MediaTypeFactory.getMediaType("file.foobar").isPresent());
+	}
+
+	@Test
+	public void nullParameter() {
+		assertFalse(MediaTypeFactory.getMediaType((String) null).isPresent());
+		assertFalse(MediaTypeFactory.getMediaType((Resource) null).isPresent());
+		assertTrue(MediaTypeFactory.getMediaTypes(null).isEmpty());
 	}
 
 }
\ No newline at end of file
diff --git a/spring-web/src/test/java/org/springframework/mock/web/test/MockServletContext.java b/spring-web/src/test/java/org/springframework/mock/web/test/MockServletContext.java
index eb0bc996b7..6dcacadcd9 100644
--- a/spring-web/src/test/java/org/springframework/mock/web/test/MockServletContext.java
+++ b/spring-web/src/test/java/org/springframework/mock/web/test/MockServletContext.java
@@ -262,14 +262,12 @@ public class MockServletContext implements ServletContext {
 	@Override
 	public String getMimeType(String filePath) {
 		String extension = StringUtils.getFilenameExtension(filePath);
-		MediaType result;
 		if (this.mimeTypes.containsKey(extension)) {
-			result = this.mimeTypes.get(extension);
+			return this.mimeTypes.get(extension).toString();
 		}
 		else {
-			result = MediaTypeFactory.getMediaType(filePath);
+			return MediaTypeFactory.getMediaType(filePath).orElse(MediaType.APPLICATION_OCTET_STREAM).toString();
 		}
-		return result != null ? result.toString() : null;
 	}
 
 	/**
diff --git a/spring-webflux/src/main/java/org/springframework/web/reactive/accept/PathExtensionContentTypeResolver.java b/spring-webflux/src/main/java/org/springframework/web/reactive/accept/PathExtensionContentTypeResolver.java
index d32bdde74f..a7944b41b9 100644
--- a/spring-webflux/src/main/java/org/springframework/web/reactive/accept/PathExtensionContentTypeResolver.java
+++ b/spring-webflux/src/main/java/org/springframework/web/reactive/accept/PathExtensionContentTypeResolver.java
@@ -18,6 +18,7 @@ package org.springframework.web.reactive.accept;
 
 import java.util.Locale;
 import java.util.Map;
+import java.util.Optional;
 
 import org.springframework.core.io.Resource;
 import org.springframework.http.MediaType;
@@ -79,9 +80,9 @@ public class PathExtensionContentTypeResolver extends AbstractMappingContentType
 
 	@Override
 	protected MediaType handleNoMatch(String key) throws NotAcceptableStatusException {
-		MediaType mediaType = MediaTypeFactory.getMediaType("file." + key);
-		if (mediaType != null) {
-			return mediaType;
+		Optional<MediaType> mediaType = MediaTypeFactory.getMediaType("file." + key);
+		if (mediaType.isPresent()) {
+			return mediaType.get();
 		}
 		if (!this.ignoreUnknownExtensions) {
 			throw new NotAcceptableStatusException(getAllMediaTypes());
@@ -105,7 +106,7 @@ public class PathExtensionContentTypeResolver extends AbstractMappingContentType
 			mediaType = getMediaType(extension);
 		}
 		if (mediaType == null) {
-			mediaType = MediaTypeFactory.getMediaType(filename);
+			mediaType = MediaTypeFactory.getMediaType(filename).orElse(null);
 		}
 		return mediaType;
 	}