001/* 002 * Copyright 2002-2017 the original author or authors. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * https://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package org.springframework.web.multipart; 018 019import java.io.File; 020import java.io.IOException; 021import java.io.InputStream; 022 023import org.springframework.core.io.InputStreamSource; 024 025/** 026 * A representation of an uploaded file received in a multipart request. 027 * 028 * <p>The file contents are either stored in memory or temporarily on disk. 029 * In either case, the user is responsible for copying file contents to a 030 * session-level or persistent store as and if desired. The temporary storage 031 * will be cleared at the end of request processing. 032 * 033 * @author Juergen Hoeller 034 * @author Trevor D. Cook 035 * @since 29.09.2003 036 * @see org.springframework.web.multipart.MultipartHttpServletRequest 037 * @see org.springframework.web.multipart.MultipartResolver 038 */ 039public interface MultipartFile extends InputStreamSource { 040 041 /** 042 * Return the name of the parameter in the multipart form. 043 * @return the name of the parameter (never {@code null} or empty) 044 */ 045 String getName(); 046 047 /** 048 * Return the original filename in the client's filesystem. 049 * <p>This may contain path information depending on the browser used, 050 * but it typically will not with any other than Opera. 051 * @return the original filename, or the empty String if no file has been chosen 052 * in the multipart form, or {@code null} if not defined or not available 053 * @see org.apache.commons.fileupload.FileItem#getName() 054 * @see org.springframework.web.multipart.commons.CommonsMultipartFile#setPreserveFilename 055 */ 056 String getOriginalFilename(); 057 058 /** 059 * Return the content type of the file. 060 * @return the content type, or {@code null} if not defined 061 * (or no file has been chosen in the multipart form) 062 */ 063 String getContentType(); 064 065 /** 066 * Return whether the uploaded file is empty, that is, either no file has 067 * been chosen in the multipart form or the chosen file has no content. 068 */ 069 boolean isEmpty(); 070 071 /** 072 * Return the size of the file in bytes. 073 * @return the size of the file, or 0 if empty 074 */ 075 long getSize(); 076 077 /** 078 * Return the contents of the file as an array of bytes. 079 * @return the contents of the file as bytes, or an empty byte array if empty 080 * @throws IOException in case of access errors (if the temporary store fails) 081 */ 082 byte[] getBytes() throws IOException; 083 084 /** 085 * Return an InputStream to read the contents of the file from. 086 * <p>The user is responsible for closing the returned stream. 087 * @return the contents of the file as stream, or an empty stream if empty 088 * @throws IOException in case of access errors (if the temporary store fails) 089 */ 090 @Override 091 InputStream getInputStream() throws IOException; 092 093 /** 094 * Transfer the received file to the given destination file. 095 * <p>This may either move the file in the filesystem, copy the file in the 096 * filesystem, or save memory-held contents to the destination file. If the 097 * destination file already exists, it will be deleted first. 098 * <p>If the target file has been moved in the filesystem, this operation 099 * cannot be invoked again afterwards. Therefore, call this method just once 100 * in order to work with any storage mechanism. 101 * <p><b>NOTE:</b> Depending on the underlying provider, temporary storage 102 * may be container-dependent, including the base directory for relative 103 * destinations specified here (e.g. with Servlet 3.0 multipart handling). 104 * For absolute destinations, the target file may get renamed/moved from its 105 * temporary location or newly copied, even if a temporary copy already exists. 106 * @param dest the destination file (typically absolute) 107 * @throws IOException in case of reading or writing errors 108 * @throws IllegalStateException if the file has already been moved 109 * in the filesystem and is not available anymore for another transfer 110 * @see org.apache.commons.fileupload.FileItem#write(File) 111 * @see javax.servlet.http.Part#write(String) 112 */ 113 void transferTo(File dest) throws IOException, IllegalStateException; 114 115}