Avoid triggering lazy resolution in MultipartResolver.cleanupMultipart

Issue: SPR-16640

(cherry picked from commit 10cb2cc)

Author: jhoeller

spring-web/src/main/java/org/springframework/web/multipart/commons/CommonsMultipartResolver.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -33,6 +33,7 @@
 import org.springframework.web.multipart.MultipartException;
 import org.springframework.web.multipart.MultipartHttpServletRequest;
 import org.springframework.web.multipart.MultipartResolver;
+import org.springframework.web.multipart.support.AbstractMultipartHttpServletRequest;
 import org.springframework.web.multipart.support.DefaultMultipartHttpServletRequest;
 import org.springframework.web.util.WebUtils;
 
@@ -189,7 +190,8 @@ protected String determineEncoding(HttpServletRequest request) {
 
 	@Override
 	public void cleanupMultipart(MultipartHttpServletRequest request) {
-		if (request != null) {
+		if (!(request instanceof AbstractMultipartHttpServletRequest) ||
+				((AbstractMultipartHttpServletRequest) request).isResolved()) {
 			try {
 				cleanupFileItems(request.getMultiFileMap());
 			}

spring-web/src/main/java/org/springframework/web/multipart/support/AbstractMultipartHttpServletRequest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -106,6 +106,18 @@ public MultiValueMap<String, MultipartFile> getMultiFileMap() {
 		return getMultipartFiles();
 	}
 
+	/**
+	 * Determine whether the underlying multipart request has been resolved.
+	 * @return {@code true} when eagerly initialized or lazily triggered,
+	 * {@code false} in case of a lazy-resolution request that got aborted
+	 * before any parameters or multipart files have been accessed
+	 * @since 4.3.15
+	 * @see #getMultipartFiles()
+	 */
+	public boolean isResolved() {
+		return (this.multipartFiles != null);
+	}
+
 
 	/**
 	 * Set a Map with parameter names as keys and list of MultipartFile objects as values.

spring-web/src/main/java/org/springframework/web/multipart/support/StandardMultipartHttpServletRequest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -48,6 +48,7 @@
  * @author Juergen Hoeller
  * @author Rossen Stoyanchev
  * @since 3.1
+ * @see StandardServletMultipartResolver
  */
 public class StandardMultipartHttpServletRequest extends AbstractMultipartHttpServletRequest {
 
@@ -79,8 +80,11 @@ public StandardMultipartHttpServletRequest(HttpServletRequest request) throws Mu
 	 * @param lazyParsing whether multipart parsing should be triggered lazily on
 	 * first access of multipart files or parameters
 	 * @throws MultipartException if an immediate parsing attempt failed
+	 * @since 3.2.9
 	 */
-	public StandardMultipartHttpServletRequest(HttpServletRequest request, boolean lazyParsing) throws MultipartException {
+	public StandardMultipartHttpServletRequest(HttpServletRequest request, boolean lazyParsing)
+			throws MultipartException {
+
 		super(request);
 		if (!lazyParsing) {
 			parseRequest(request);

spring-web/src/main/java/org/springframework/web/multipart/support/StandardServletMultipartResolver.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -59,6 +59,7 @@ public class StandardServletMultipartResolver implements MultipartResolver {
 	 * corresponding exceptions at the time of the {@link #resolveMultipart} call.
 	 * Switch this to "true" for lazy multipart parsing, throwing parse exceptions
 	 * once the application attempts to obtain multipart files or parameters.
+	 * @since 3.2.9
 	 */
 	public void setResolveLazily(boolean resolveLazily) {
 		this.resolveLazily = resolveLazily;
@@ -82,17 +83,20 @@ public MultipartHttpServletRequest resolveMultipart(HttpServletRequest request)
 
 	@Override
 	public void cleanupMultipart(MultipartHttpServletRequest request) {
-		// To be on the safe side: explicitly delete the parts,
-		// but only actual file parts (for Resin compatibility)
-		try {
-			for (Part part : request.getParts()) {
-				if (request.getFile(part.getName()) != null) {
-					part.delete();
+		if (!(request instanceof AbstractMultipartHttpServletRequest) ||
+				((AbstractMultipartHttpServletRequest) request).isResolved()) {
+			// To be on the safe side: explicitly delete the parts,
+			// but only actual file parts (for Resin compatibility)
+			try {
+				for (Part part : request.getParts()) {
+					if (request.getFile(part.getName()) != null) {
+						part.delete();
+					}
 				}
 			}
-		}
-		catch (Throwable ex) {
-			LogFactory.getLog(getClass()).warn("Failed to perform cleanup of multipart items", ex);
+			catch (Throwable ex) {
+				LogFactory.getLog(getClass()).warn("Failed to perform cleanup of multipart items", ex);
+			}
 		}
 	}