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/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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
*
* http://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.
*/
/**
*
* A component for handling HTML file uploads as specified by
* RFC 1867. This component provides support for uploads within
* both servlets (JSR 53) and portlets (JSR 168).
*
*
* While this package provides the generic functionality for file uploads, these
* classes are not typically used directly. Instead, normal usage involves one
* of the provided extensions of
* {@link com.vaadin.external.apache.commons.fileupload2.FileUpload FileUpload}
* such as
* {@link com.vaadin.external.apache.commons.fileupload2.jaksrvlt.JakSrvltFileUpload
* ServletFileUpload} or , together with a factory for
* {@link com.vaadin.external.apache.commons.fileupload2.FileItem FileItem}
* instances, such as
* {@link com.vaadin.external.apache.commons.fileupload2.disk.DiskFileItemFactory
* DiskFileItemFactory}.
*
*
* The following is a brief example of typical usage in a servlet, storing the
* uploaded files on disk.
*
*
*
* public void doPost(HttpServletRequest req, HttpServletResponse res) {
* DiskFileItemFactory factory = new DiskFileItemFactory();
* // maximum size that will be stored in memory
* factory.setSizeThreshold(4096);
* // the location for saving data that is larger than getSizeThreshold()
* factory.setRepository(new File("/tmp"));
*
* ServletFileUpload upload = new ServletFileUpload(factory);
* // maximum size before a FileUploadException will be thrown
* upload.setSizeMax(1000000);
*
* List fileItems = upload.parseRequest(req);
* // assume we know there are two files. The first file is a small
* // text file, the second is unknown and is written to a file on
* // the server
* Iterator i = fileItems.iterator();
* String comment = ((FileItem)i.next()).getString();
* FileItem fi = (FileItem)i.next();
* // file name on the client
* String fileName = fi.getName();
* // save comment and file name to database
* ...
* // write the file
* fi.write(new File("/www/uploads/", fileName));
* }
*
*
* In the example above, the first file is loaded into memory as a
* {@code String}. Before calling the {@code getString} method, the data may
* have been in memory or on disk depending on its size. The second file we
* assume it will be large and therefore never explicitly load it into memory,
* though if it is less than 4096 bytes it will be in memory before it is
* written to its final location. When writing to the final location, if the
* data is larger than the threshold, an attempt is made to rename the temporary
* file to the given location. If it cannot be renamed, it is streamed to the
* new location.
*
*
* Please see the FileUpload
* User
* Guide for further details and examples of how to use this package.
*
*/
package com.vaadin.external.apache.commons.fileupload2;