DispatcherServlet's checkMultipart detects wrapped MultipartRequest as well

Issue: SPR-12114
(cherry picked from commit 786fd92)

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

@@ -1033,7 +1033,7 @@ public class DispatcherServlet extends FrameworkServlet {
 	 */
 	protected HttpServletRequest checkMultipart(HttpServletRequest request) throws MultipartException {
 		if (this.multipartResolver != null && this.multipartResolver.isMultipart(request)) {
-			if (request instanceof MultipartHttpServletRequest) {
+			if (WebUtils.getNativeRequest(request, MultipartHttpServletRequest.class) != null) {
 				logger.debug("Request is already a MultipartHttpServletRequest - if not in a forward, " +
 						"this typically results from an additional MultipartFilter in web.xml");
 			}
@@ -1047,13 +1047,13 @@ public class DispatcherServlet extends FrameworkServlet {
 
 	/**
 	 * Clean up any resources used by the given multipart request (if any).
-	 * @param servletRequest current HTTP request
+	 * @param request current HTTP request
 	 * @see MultipartResolver#cleanupMultipart
 	 */
-	protected void cleanupMultipart(HttpServletRequest servletRequest) {
-		MultipartHttpServletRequest req = WebUtils.getNativeRequest(servletRequest, MultipartHttpServletRequest.class);
-		if (req != null) {
-			this.multipartResolver.cleanupMultipart(req);
+	protected void cleanupMultipart(HttpServletRequest request) {
+		MultipartHttpServletRequest multipartRequest = WebUtils.getNativeRequest(request, MultipartHttpServletRequest.class);
+		if (multipartRequest != null) {
+			this.multipartResolver.cleanupMultipart(multipartRequest);
 		}
 	}
 

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2014 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -66,6 +66,7 @@ import org.springframework.web.servlet.theme.SessionThemeResolver;
 import org.springframework.web.servlet.theme.ThemeChangeInterceptor;
 import org.springframework.web.servlet.view.InternalResourceViewResolver;
 import org.springframework.web.servlet.view.ResourceBundleViewResolver;
+import org.springframework.web.util.WebUtils;
 
 /**
  * @author Juergen Hoeller
@@ -405,7 +406,7 @@ public class ComplexWebApplicationContext extends StaticWebApplicationContext {
 			if (!(wac instanceof ComplexWebApplicationContext)) {
 				throw new ServletException("Incorrect WebApplicationContext");
 			}
-			if (!(request instanceof MultipartHttpServletRequest)) {
+			if (WebUtils.getNativeRequest(request, MultipartHttpServletRequest.class) == null) {
 				throw new ServletException("Not in a MultipartHttpServletRequest");
 			}
 			if (!(RequestContextUtils.getLocaleResolver(request) instanceof SessionLocaleResolver)) {

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2014 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -23,6 +23,7 @@ import javax.servlet.ServletConfig;
 import javax.servlet.ServletContext;
 import javax.servlet.ServletException;
 import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletRequestWrapper;
 import javax.servlet.http.HttpServletResponse;
 
 import junit.framework.TestCase;
@@ -305,6 +306,22 @@ public class DispatcherServletTests extends TestCase {
 		MultipartHttpServletRequest multipartRequest = multipartResolver.resolveMultipart(request);
 		complexDispatcherServlet.service(multipartRequest, response);
 		multipartResolver.cleanupMultipart(multipartRequest);
+		assertNull(request.getAttribute(SimpleMappingExceptionResolver.DEFAULT_EXCEPTION_ATTRIBUTE));
+		assertNotNull(request.getAttribute("cleanedUp"));
+	}
+
+	public void testExistingMultipartRequestButWrapped() throws Exception {
+		MockHttpServletRequest request = new MockHttpServletRequest(getServletContext(), "GET", "/locale.do;abc=def");
+		request.addPreferredLocale(Locale.CANADA);
+		request.addUserRole("role1");
+		MockHttpServletResponse response = new MockHttpServletResponse();
+		ComplexWebApplicationContext.MockMultipartResolver multipartResolver =
+				(ComplexWebApplicationContext.MockMultipartResolver) complexDispatcherServlet.getWebApplicationContext()
+						.getBean("multipartResolver");
+		MultipartHttpServletRequest multipartRequest = multipartResolver.resolveMultipart(request);
+		complexDispatcherServlet.service(new HttpServletRequestWrapper(multipartRequest), response);
+		multipartResolver.cleanupMultipart(multipartRequest);
+		assertNull(request.getAttribute(SimpleMappingExceptionResolver.DEFAULT_EXCEPTION_ATTRIBUTE));
 		assertNotNull(request.getAttribute("cleanedUp"));
 	}