SPR-6466 - ContentNegotiatingViewResolver can not handle View implementations returning null as content type

Author: poutsma

org.springframework.web.servlet/src/main/java/org/springframework/web/servlet/view/ContentNegotiatingViewResolver.java

@@ -350,12 +350,15 @@ public View resolveViewName(String viewName, Locale locale) throws Exception {
 		}
 
 		for (View candidateView : candidateViews) {
-			MediaType viewMediaType = MediaType.parseMediaType(candidateView.getContentType());
-			for (MediaType requestedMediaType : requestedMediaTypes) {
-				if (requestedMediaType.includes(viewMediaType)) {
-					if (!views.containsKey(requestedMediaType)) {
-						views.put(requestedMediaType, candidateView);
-						break;
+			String contentType = candidateView.getContentType();
+			if (StringUtils.hasText(contentType)) {
+				MediaType viewMediaType = MediaType.parseMediaType(contentType);
+				for (MediaType requestedMediaType : requestedMediaTypes) {
+					if (requestedMediaType.includes(viewMediaType)) {
+						if (!views.containsKey(requestedMediaType)) {
+							views.put(requestedMediaType, candidateView);
+							break;
+						}
 					}
 				}
 			}

org.springframework.web.servlet/src/test/java/org/springframework/web/servlet/view/ContentNegotiatingViewResolverTests.java

@@ -280,4 +280,29 @@ public void resolveViewNameFilenameDefaultView() throws Exception {
 		verify(viewResolverMock1, viewResolverMock2, viewMock1, viewMock2, viewMock3);
 	}
 
+	@Test
+	public void resolveViewContentTypeNull() throws Exception {
+		MockHttpServletRequest request = new MockHttpServletRequest("GET", "/test");
+		request.addHeader("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8");
+		RequestContextHolder.setRequestAttributes(new ServletRequestAttributes(request));
+
+		ViewResolver viewResolverMock = createMock(ViewResolver.class);
+		viewResolver.setViewResolvers(Collections.singletonList(viewResolverMock));
+
+		View viewMock = createMock("application_xml", View.class);
+
+		String viewName = "view";
+		Locale locale = Locale.ENGLISH;
+
+		expect(viewResolverMock.resolveViewName(viewName, locale)).andReturn(viewMock);
+		expect(viewMock.getContentType()).andReturn(null);
+
+		replay(viewResolverMock, viewMock);
+
+		View result = viewResolver.resolveViewName(viewName, locale);
+		assertNull("Invalid view", result);
+
+		verify(viewResolverMock, viewMock);
+	}
+
 }