Java tutorial
/* * 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.support; import java.io.File; import java.io.IOException; import java.io.InputStream; import java.io.Serializable; import java.io.UnsupportedEncodingException; import java.nio.file.Files; import java.nio.file.Path; import java.util.ArrayList; import java.util.Collection; import java.util.Collections; import java.util.Enumeration; import java.util.LinkedHashMap; import java.util.LinkedHashSet; import java.util.Map; import java.util.Set; import javax.mail.internet.MimeUtility; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.Part; import org.springframework.http.ContentDisposition; import org.springframework.http.HttpHeaders; import org.springframework.lang.Nullable; import org.springframework.util.FileCopyUtils; import org.springframework.util.LinkedMultiValueMap; import org.springframework.util.MultiValueMap; import org.springframework.web.multipart.MaxUploadSizeExceededException; import org.springframework.web.multipart.MultipartException; import org.springframework.web.multipart.MultipartFile; /** * Spring MultipartHttpServletRequest adapter, wrapping a Servlet 3.0 HttpServletRequest * and its Part objects. Parameters get exposed through the native request's getParameter * methods - without any custom processing on our side. * * @author Juergen Hoeller * @author Rossen Stoyanchev * @since 3.1 * @see StandardServletMultipartResolver */ public class StandardMultipartHttpServletRequest extends AbstractMultipartHttpServletRequest { @Nullable private Set<String> multipartParameterNames; /** * Create a new StandardMultipartHttpServletRequest wrapper for the given request, * immediately parsing the multipart content. * @param request the servlet request to wrap * @throws MultipartException if parsing failed */ public StandardMultipartHttpServletRequest(HttpServletRequest request) throws MultipartException { this(request, false); } /** * Create a new StandardMultipartHttpServletRequest wrapper for the given request. * @param request the servlet request to wrap * @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 { super(request); if (!lazyParsing) { parseRequest(request); } } private void parseRequest(HttpServletRequest request) { try { Collection<Part> parts = request.getParts(); this.multipartParameterNames = new LinkedHashSet<>(parts.size()); MultiValueMap<String, MultipartFile> files = new LinkedMultiValueMap<>(parts.size()); for (Part part : parts) { String headerValue = part.getHeader(HttpHeaders.CONTENT_DISPOSITION); ContentDisposition disposition = ContentDisposition.parse(headerValue); String filename = disposition.getFilename(); if (filename != null) { if (filename.startsWith("=?") && filename.endsWith("?=")) { filename = MimeDelegate.decode(filename); } files.add(part.getName(), new StandardMultipartFile(part, filename)); } else { this.multipartParameterNames.add(part.getName()); } } setMultipartFiles(files); } catch (Throwable ex) { handleParseFailure(ex); } } protected void handleParseFailure(Throwable ex) { String msg = ex.getMessage(); if (msg != null && msg.contains("size") && msg.contains("exceed")) { throw new MaxUploadSizeExceededException(-1, ex); } throw new MultipartException("Failed to parse multipart servlet request", ex); } @Override protected void initializeMultipart() { parseRequest(getRequest()); } @Override public Enumeration<String> getParameterNames() { if (this.multipartParameterNames == null) { initializeMultipart(); } if (this.multipartParameterNames.isEmpty()) { return super.getParameterNames(); } // Servlet 3.0 getParameterNames() not guaranteed to include multipart form items // (e.g. on WebLogic 12) -> need to merge them here to be on the safe side Set<String> paramNames = new LinkedHashSet<>(); Enumeration<String> paramEnum = super.getParameterNames(); while (paramEnum.hasMoreElements()) { paramNames.add(paramEnum.nextElement()); } paramNames.addAll(this.multipartParameterNames); return Collections.enumeration(paramNames); } @Override public Map<String, String[]> getParameterMap() { if (this.multipartParameterNames == null) { initializeMultipart(); } if (this.multipartParameterNames.isEmpty()) { return super.getParameterMap(); } // Servlet 3.0 getParameterMap() not guaranteed to include multipart form items // (e.g. on WebLogic 12) -> need to merge them here to be on the safe side Map<String, String[]> paramMap = new LinkedHashMap<>(super.getParameterMap()); for (String paramName : this.multipartParameterNames) { if (!paramMap.containsKey(paramName)) { paramMap.put(paramName, getParameterValues(paramName)); } } return paramMap; } @Override public String getMultipartContentType(String paramOrFileName) { try { Part part = getPart(paramOrFileName); return (part != null ? part.getContentType() : null); } catch (Throwable ex) { throw new MultipartException("Could not access multipart servlet request", ex); } } @Override public HttpHeaders getMultipartHeaders(String paramOrFileName) { try { Part part = getPart(paramOrFileName); if (part != null) { HttpHeaders headers = new HttpHeaders(); for (String headerName : part.getHeaderNames()) { headers.put(headerName, new ArrayList<>(part.getHeaders(headerName))); } return headers; } else { return null; } } catch (Throwable ex) { throw new MultipartException("Could not access multipart servlet request", ex); } } /** * Spring MultipartFile adapter, wrapping a Servlet 3.0 Part object. */ @SuppressWarnings("serial") private static class StandardMultipartFile implements MultipartFile, Serializable { private final Part part; private final String filename; public StandardMultipartFile(Part part, String filename) { this.part = part; this.filename = filename; } @Override public String getName() { return this.part.getName(); } @Override public String getOriginalFilename() { return this.filename; } @Override public String getContentType() { return this.part.getContentType(); } @Override public boolean isEmpty() { return (this.part.getSize() == 0); } @Override public long getSize() { return this.part.getSize(); } @Override public byte[] getBytes() throws IOException { return FileCopyUtils.copyToByteArray(this.part.getInputStream()); } @Override public InputStream getInputStream() throws IOException { return this.part.getInputStream(); } @Override public void transferTo(File dest) throws IOException, IllegalStateException { this.part.write(dest.getPath()); if (dest.isAbsolute() && !dest.exists()) { // Servlet 3.0 Part.write is not guaranteed to support absolute file paths: // may translate the given path to a relative location within a temp dir // (e.g. on Jetty whereas Tomcat and Undertow detect absolute paths). // At least we offloaded the file from memory storage; it'll get deleted // from the temp dir eventually in any case. And for our user's purposes, // we can manually copy it to the requested location as a fallback. FileCopyUtils.copy(this.part.getInputStream(), Files.newOutputStream(dest.toPath())); } } @Override public void transferTo(Path dest) throws IOException, IllegalStateException { FileCopyUtils.copy(this.part.getInputStream(), Files.newOutputStream(dest)); } } /** * Inner class to avoid a hard dependency on the JavaMail API. */ private static class MimeDelegate { public static String decode(String value) { try { return MimeUtility.decodeText(value); } catch (UnsupportedEncodingException ex) { throw new IllegalStateException(ex); } } } }