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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package org.apache.commons.fileupload.servlet;
18  
19  import java.io.IOException;
20  import java.util.List;
21  import java.util.Map;
22  
23  import javax.servlet.http.HttpServletRequest;
24  
25  import org.apache.commons.fileupload.FileItem;
26  import org.apache.commons.fileupload.FileItemFactory;
27  import org.apache.commons.fileupload.FileItemIterator;
28  import org.apache.commons.fileupload.FileUpload;
29  import org.apache.commons.fileupload.FileUploadBase;
30  import org.apache.commons.fileupload.FileUploadException;
31  
32  /**
33   * <p>High level API for processing file uploads.</p>
34   *
35   * <p>This class handles multiple files per single HTML widget, sent using
36   * {@code multipart/mixed} encoding type, as specified by
37   * <a href="http://www.ietf.org/rfc/rfc1867.txt">RFC 1867</a>.  Use {@link
38   * #parseRequest(HttpServletRequest)} to acquire a list of {@link
39   * org.apache.commons.fileupload.FileItem}s associated with a given HTML
40   * widget.</p>
41   *
42   * <p>How the data for individual parts is stored is determined by the factory
43   * used to create them; a given part may be in memory, on disk, or somewhere
44   * else.</p>
45   */
46  public class ServletFileUpload extends FileUpload {
47  
48      /**
49       * Constant for HTTP POST method.
50       */
51      private static final String POST_METHOD = "POST";
52  
53      /**
54       * Utility method that determines whether the request contains multipart
55       * content.
56       *
57       * @param request The servlet request to be evaluated. Must be non-null.
58       * @return {@code true} if the request is multipart;
59       *         {@code false} otherwise.
60       */
61      public static final boolean isMultipartContent(
62              final HttpServletRequest request) {
63          if (!POST_METHOD.equalsIgnoreCase(request.getMethod())) {
64              return false;
65          }
66          return FileUploadBase.isMultipartContent(new ServletRequestContext(request));
67      }
68  
69      /**
70       * Constructs an uninitialized instance of this class. A factory must be
71       * configured, using {@code setFileItemFactory()}, before attempting
72       * to parse requests.
73       *
74       * @see FileUpload#FileUpload(FileItemFactory)
75       */
76      public ServletFileUpload() {
77      }
78  
79      /**
80       * Constructs an instance of this class which uses the supplied factory to
81       * create {@code FileItem} instances.
82       *
83       * @see FileUpload#FileUpload()
84       * @param fileItemFactory The factory to use for creating file items.
85       */
86      public ServletFileUpload(final FileItemFactory fileItemFactory) {
87          super(fileItemFactory);
88      }
89  
90      /**
91       * Processes an <a href="http://www.ietf.org/rfc/rfc1867.txt">RFC 1867</a>
92       * compliant {@code multipart/form-data} stream.
93       *
94       * @param request The servlet request to be parsed.
95       * @return An iterator to instances of {@code FileItemStream}
96       *         parsed from the request, in the order that they were
97       *         transmitted.
98       *
99       * @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 }