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/* * Copyright 2002-2019 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.io.File; import java.io.IOException; import java.io.InputStream; import java.io.Serializable; import java.nio.file.Files; import java.nio.file.Path; import org.apache.commons.fileupload.FileItem; import org.apache.commons.fileupload.FileUploadException; import org.apache.commons.fileupload.disk.DiskFileItem; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.core.log.LogFormatUtils; import org.springframework.util.FileCopyUtils; import org.springframework.util.StreamUtils; import org.springframework.web.multipart.MultipartFile; /** * {@link MultipartFile} implementation for Apache Commons FileUpload. * * @author Trevor D. Cook * @author Juergen Hoeller * @since 29.09.2003 * @see CommonsMultipartResolver */ @SuppressWarnings("serial") public class CommonsMultipartFile implements MultipartFile, Serializable { protected static final Log logger = LogFactory.getLog(CommonsMultipartFile.class); private final FileItem fileItem; private final long size; private boolean preserveFilename = false; /** * Create an instance wrapping the given FileItem. * @param fileItem the FileItem to wrap */ public CommonsMultipartFile(FileItem fileItem) { this.fileItem = fileItem; this.size = this.fileItem.getSize(); } /** * Return the underlying {@code org.apache.commons.fileupload.FileItem} * instance. There is hardly any need to access this. */ public final FileItem getFileItem() { return this.fileItem; } /** * Set whether to preserve the filename as sent by the client, not stripping off * path information in {@link CommonsMultipartFile#getOriginalFilename()}. * <p>Default is "false", stripping off path information that may prefix the * actual filename e.g. from Opera. Switch this to "true" for preserving the * client-specified filename as-is, including potential path separators. * @since 4.3.5 * @see #getOriginalFilename() * @see CommonsMultipartResolver#setPreserveFilename(boolean) */ public void setPreserveFilename(boolean preserveFilename) { this.preserveFilename = preserveFilename; } @Override public String getName() { return this.fileItem.getFieldName(); } @Override public String getOriginalFilename() { String filename = this.fileItem.getName(); if (filename == null) { // Should never happen. return ""; } if (this.preserveFilename) { // Do not try to strip off a path... return filename; } // Check for Unix-style path int unixSep = filename.lastIndexOf('/'); // Check for Windows-style path int winSep = filename.lastIndexOf('\\'); // Cut off at latest possible point int pos = Math.max(winSep, unixSep); if (pos != -1) { // Any sort of path separator found... return filename.substring(pos + 1); } else { // A plain name return filename; } } @Override public String getContentType() { return this.fileItem.getContentType(); } @Override public boolean isEmpty() { return (this.size == 0); } @Override public long getSize() { return this.size; } @Override public byte[] getBytes() { if (!isAvailable()) { throw new IllegalStateException("File has been moved - cannot be read again"); } byte[] bytes = this.fileItem.get(); return (bytes != null ? bytes : new byte[0]); } @Override public InputStream getInputStream() throws IOException { if (!isAvailable()) { throw new IllegalStateException("File has been moved - cannot be read again"); } InputStream inputStream = this.fileItem.getInputStream(); return (inputStream != null ? inputStream : StreamUtils.emptyInput()); } @Override public void transferTo(File dest) throws IOException, IllegalStateException { if (!isAvailable()) { throw new IllegalStateException("File has already been moved - cannot be transferred again"); } if (dest.exists() && !dest.delete()) { throw new IOException( "Destination file [" + dest.getAbsolutePath() + "] already exists and could not be deleted"); } try { this.fileItem.write(dest); LogFormatUtils.traceDebug(logger, traceOn -> { String action = "transferred"; if (!this.fileItem.isInMemory()) { action = (isAvailable() ? "copied" : "moved"); } return "Part '" + getName() + "', filename '" + getOriginalFilename() + "'" + (traceOn ? ", stored " + getStorageDescription() : "") + ": " + action + " to [" + dest.getAbsolutePath() + "]"; }); } catch (FileUploadException ex) { throw new IllegalStateException(ex.getMessage(), ex); } catch (IllegalStateException | IOException ex) { // Pass through IllegalStateException when coming from FileItem directly, // or propagate an exception from I/O operations within FileItem.write throw ex; } catch (Exception ex) { throw new IOException("File transfer failed", ex); } } @Override public void transferTo(Path dest) throws IOException, IllegalStateException { if (!isAvailable()) { throw new IllegalStateException("File has already been moved - cannot be transferred again"); } FileCopyUtils.copy(this.fileItem.getInputStream(), Files.newOutputStream(dest)); } /** * Determine whether the multipart content is still available. * If a temporary file has been moved, the content is no longer available. */ protected boolean isAvailable() { // If in memory, it's available. if (this.fileItem.isInMemory()) { return true; } // Check actual existence of temporary file. if (this.fileItem instanceof DiskFileItem) { return ((DiskFileItem) this.fileItem).getStoreLocation().exists(); } // Check whether current file size is different than original one. return (this.fileItem.getSize() == this.size); } /** * Return a description for the storage location of the multipart content. * Tries to be as specific as possible: mentions the file location in case * of a temporary file. */ public String getStorageDescription() { if (this.fileItem.isInMemory()) { return "in memory"; } else if (this.fileItem instanceof DiskFileItem) { return "at [" + ((DiskFileItem) this.fileItem).getStoreLocation().getAbsolutePath() + "]"; } else { return "on disk"; } } }