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/* * 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. * You may obtain a copy of the License at * * https://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.springframework.web.multipart.commons; import java.util.List; import javax.servlet.ServletContext; import javax.servlet.http.HttpServletRequest; import org.apache.commons.fileupload.FileItem; import org.apache.commons.fileupload.FileItemFactory; import org.apache.commons.fileupload.FileUpload; import org.apache.commons.fileupload.FileUploadBase; import org.apache.commons.fileupload.FileUploadException; import org.apache.commons.fileupload.servlet.ServletFileUpload; import org.springframework.util.Assert; import org.springframework.web.context.ServletContextAware; import org.springframework.web.multipart.MaxUploadSizeExceededException; 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; /** * Servlet-based {@link MultipartResolver} implementation for * <a href="https://commons.apache.org/proper/commons-fileupload">Apache Commons FileUpload</a> * 1.2 or above. * * <p>Provides "maxUploadSize", "maxInMemorySize" and "defaultEncoding" settings as * bean properties (inherited from {@link CommonsFileUploadSupport}). See corresponding * ServletFileUpload / DiskFileItemFactory properties ("sizeMax", "sizeThreshold", * "headerEncoding") for details in terms of defaults and accepted values. * * <p>Saves temporary files to the servlet container's temporary directory. * Needs to be initialized <i>either</i> by an application context <i>or</i> * via the constructor that takes a ServletContext (for standalone usage). * * @author Trevor D. Cook * @author Juergen Hoeller * @since 29.09.2003 * @see #CommonsMultipartResolver(ServletContext) * @see #setResolveLazily * @see org.apache.commons.fileupload.servlet.ServletFileUpload * @see org.apache.commons.fileupload.disk.DiskFileItemFactory */ public class CommonsMultipartResolver extends CommonsFileUploadSupport implements MultipartResolver, ServletContextAware { private boolean resolveLazily = false; /** * Constructor for use as bean. Determines the servlet container's * temporary directory via the ServletContext passed in as through the * ServletContextAware interface (typically by a WebApplicationContext). * @see #setServletContext * @see org.springframework.web.context.ServletContextAware * @see org.springframework.web.context.WebApplicationContext */ public CommonsMultipartResolver() { super(); } /** * Constructor for standalone usage. Determines the servlet container's * temporary directory via the given ServletContext. * @param servletContext the ServletContext to use */ public CommonsMultipartResolver(ServletContext servletContext) { this(); setServletContext(servletContext); } /** * Set whether to resolve the multipart request lazily at the time of * file or parameter access. * <p>Default is "false", resolving the multipart elements immediately, throwing * 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. */ public void setResolveLazily(boolean resolveLazily) { this.resolveLazily = resolveLazily; } /** * Initialize the underlying {@code org.apache.commons.fileupload.servlet.ServletFileUpload} * instance. Can be overridden to use a custom subclass, e.g. for testing purposes. * @param fileItemFactory the Commons FileItemFactory to use * @return the new ServletFileUpload instance */ @Override protected FileUpload newFileUpload(FileItemFactory fileItemFactory) { return new ServletFileUpload(fileItemFactory); } @Override public void setServletContext(ServletContext servletContext) { if (!isUploadTempDirSpecified()) { getFileItemFactory().setRepository(WebUtils.getTempDir(servletContext)); } } @Override public boolean isMultipart(HttpServletRequest request) { return ServletFileUpload.isMultipartContent(request); } @Override public MultipartHttpServletRequest resolveMultipart(final HttpServletRequest request) throws MultipartException { Assert.notNull(request, "Request must not be null"); if (this.resolveLazily) { return new DefaultMultipartHttpServletRequest(request) { @Override protected void initializeMultipart() { MultipartParsingResult parsingResult = parseRequest(request); setMultipartFiles(parsingResult.getMultipartFiles()); setMultipartParameters(parsingResult.getMultipartParameters()); setMultipartParameterContentTypes(parsingResult.getMultipartParameterContentTypes()); } }; } else { MultipartParsingResult parsingResult = parseRequest(request); return new DefaultMultipartHttpServletRequest(request, parsingResult.getMultipartFiles(), parsingResult.getMultipartParameters(), parsingResult.getMultipartParameterContentTypes()); } } /** * Parse the given servlet request, resolving its multipart elements. * @param request the request to parse * @return the parsing result * @throws MultipartException if multipart resolution failed. */ protected MultipartParsingResult parseRequest(HttpServletRequest request) throws MultipartException { String encoding = determineEncoding(request); FileUpload fileUpload = prepareFileUpload(encoding); try { List<FileItem> fileItems = ((ServletFileUpload) fileUpload).parseRequest(request); return parseFileItems(fileItems, encoding); } catch (FileUploadBase.SizeLimitExceededException ex) { throw new MaxUploadSizeExceededException(fileUpload.getSizeMax(), ex); } catch (FileUploadBase.FileSizeLimitExceededException ex) { throw new MaxUploadSizeExceededException(fileUpload.getFileSizeMax(), ex); } catch (FileUploadException ex) { throw new MultipartException("Failed to parse multipart servlet request", ex); } } /** * Determine the encoding for the given request. * Can be overridden in subclasses. * <p>The default implementation checks the request encoding, * falling back to the default encoding specified for this resolver. * @param request current HTTP request * @return the encoding for the request (never {@code null}) * @see javax.servlet.ServletRequest#getCharacterEncoding * @see #setDefaultEncoding */ protected String determineEncoding(HttpServletRequest request) { String encoding = request.getCharacterEncoding(); if (encoding == null) { encoding = getDefaultEncoding(); } return encoding; } @Override public void cleanupMultipart(MultipartHttpServletRequest request) { if (!(request instanceof AbstractMultipartHttpServletRequest) || ((AbstractMultipartHttpServletRequest) request).isResolved()) { try { cleanupFileItems(request.getMultiFileMap()); } catch (Throwable ex) { logger.warn("Failed to perform multipart cleanup for servlet request", ex); } } } }