001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.commons.fileupload.servlet;
018
019import java.io.IOException;
020import java.util.List;
021import java.util.Map;
022
023import javax.servlet.http.HttpServletRequest;
024
025import org.apache.commons.fileupload.FileItem;
026import org.apache.commons.fileupload.FileItemFactory;
027import org.apache.commons.fileupload.FileItemIterator;
028import org.apache.commons.fileupload.FileUpload;
029import org.apache.commons.fileupload.FileUploadBase;
030import org.apache.commons.fileupload.FileUploadException;
031
032/**
033 * <p>High level API for processing file uploads.</p>
034 *
035 * <p>This class handles multiple files per single HTML widget, sent using
036 * {@code multipart/mixed} encoding type, as specified by
037 * <a href="http://www.ietf.org/rfc/rfc1867.txt">RFC 1867</a>.  Use {@link
038 * #parseRequest(HttpServletRequest)} to acquire a list of {@link
039 * org.apache.commons.fileupload.FileItem}s associated with a given HTML
040 * widget.</p>
041 *
042 * <p>How the data for individual parts is stored is determined by the factory
043 * used to create them; a given part may be in memory, on disk, or somewhere
044 * else.</p>
045 */
046public class ServletFileUpload extends FileUpload {
047
048    /**
049     * Constant for HTTP POST method.
050     */
051    private static final String POST_METHOD = "POST";
052
053    /**
054     * Utility method that determines whether the request contains multipart
055     * content.
056     *
057     * @param request The servlet request to be evaluated. Must be non-null.
058     * @return {@code true} if the request is multipart;
059     *         {@code false} otherwise.
060     */
061    public static final boolean isMultipartContent(
062            final HttpServletRequest request) {
063        if (!POST_METHOD.equalsIgnoreCase(request.getMethod())) {
064            return false;
065        }
066        return FileUploadBase.isMultipartContent(new ServletRequestContext(request));
067    }
068
069    /**
070     * Constructs an uninitialized instance of this class. A factory must be
071     * configured, using {@code setFileItemFactory()}, before attempting
072     * to parse requests.
073     *
074     * @see FileUpload#FileUpload(FileItemFactory)
075     */
076    public ServletFileUpload() {
077    }
078
079    /**
080     * Constructs an instance of this class which uses the supplied factory to
081     * create {@code FileItem} instances.
082     *
083     * @see FileUpload#FileUpload()
084     * @param fileItemFactory The factory to use for creating file items.
085     */
086    public ServletFileUpload(final FileItemFactory fileItemFactory) {
087        super(fileItemFactory);
088    }
089
090    /**
091     * Processes an <a href="http://www.ietf.org/rfc/rfc1867.txt">RFC 1867</a>
092     * compliant {@code multipart/form-data} stream.
093     *
094     * @param request The servlet request to be parsed.
095     * @return An iterator to instances of {@code FileItemStream}
096     *         parsed from the request, in the order that they were
097     *         transmitted.
098     *
099     * @throws FileUploadException if there are problems reading/parsing
100     *                             the request or storing files.
101     * @throws IOException An I/O error occurred. This may be a network
102     *   error while communicating with the client or a problem while
103     *   storing the uploaded content.
104     */
105    public FileItemIterator getItemIterator(final HttpServletRequest request)
106    throws FileUploadException, IOException {
107        return super.getItemIterator(new ServletRequestContext(request));
108    }
109
110    /**
111     * Processes an <a href="http://www.ietf.org/rfc/rfc1867.txt">RFC 1867</a>
112     * compliant {@code multipart/form-data} stream.
113     *
114     * @param request The servlet request to be parsed.
115     * @return A map of {@code FileItem} instances parsed from the request.
116     * @throws FileUploadException if there are problems reading/parsing
117     *                             the request or storing files.
118     *
119     * @since 1.3
120     */
121    public Map<String, List<FileItem>> parseParameterMap(final HttpServletRequest request)
122            throws FileUploadException {
123        return parseParameterMap(new ServletRequestContext(request));
124    }
125
126    /**
127     * Processes an <a href="http://www.ietf.org/rfc/rfc1867.txt">RFC 1867</a>
128     * compliant {@code multipart/form-data} stream.
129     *
130     * @param request The servlet request to be parsed.
131     * @return A list of {@code FileItem} instances parsed from the
132     *         request, in the order that they were transmitted.
133     *
134     * @throws FileUploadException if there are problems reading/parsing
135     *                             the request or storing files.
136     */
137    @Override
138    public List<FileItem> parseRequest(final HttpServletRequest request)
139    throws FileUploadException {
140        return parseRequest(new ServletRequestContext(request));
141    }
142
143}