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Java > Open Source Codes > org > apache > commons > httpclient > methods > multipart > MultipartRequestEntity


1 /*
2  * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//httpclient/src/java/org/apache/commons/httpclient/methods/multipart/MultipartRequestEntity.java,v 1.1 2004/10/06 03:39:59 mbecke Exp $
3  * $Revision: 502647 $
4  * $Date: 2007-02-02 16:22:54 +0000 (Fri, 02 Feb 2007) $
5  *
6  * ====================================================================
7  *
8  * Licensed to the Apache Software Foundation (ASF) under one or more
9  * contributor license agreements. See the NOTICE file distributed with
10  * this work for additional information regarding copyright ownership.
11  * The ASF licenses this file to You under the Apache License, Version 2.0
12  * (the "License"); you may not use this file except in compliance with
13  * the License. You may obtain a copy of the License at
14  *
15  * http://www.apache.org/licenses/LICENSE-2.0
16  *
17  * Unless required by applicable law or agreed to in writing, software
18  * distributed under the License is distributed on an "AS IS" BASIS,
19  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
20  * See the License for the specific language governing permissions and
21  * limitations under the License.
22  * ====================================================================
23  *
24  * This software consists of voluntary contributions made by many
25  * individuals on behalf of the Apache Software Foundation. For more
26  * information on the Apache Software Foundation, please see
27  * <http://www.apache.org/>.
28  *
29  */
30 package org.apache.commons.httpclient.methods.multipart;
31
32 import java.io.IOException JavaDoc;
33 import java.io.OutputStream JavaDoc;
34 import java.util.Random JavaDoc;
35
36 import org.apache.commons.httpclient.methods.RequestEntity;
37 import org.apache.commons.httpclient.params.HttpMethodParams;
38 import org.apache.commons.httpclient.util.EncodingUtil;
39 import org.apache.commons.logging.Log;
40 import org.apache.commons.logging.LogFactory;
41
42 /**
43  * Implements a request entity suitable for an HTTP multipart POST method.
44  * <p>
45  * The HTTP multipart POST method is defined in section 3.3 of
46  * <a HREF="http://www.ietf.org/rfc/rfc1867.txt">RFC1867</a>:
47  * <blockquote>
48  * The media-type multipart/form-data follows the rules of all multipart
49  * MIME data streams as outlined in RFC 1521. The multipart/form-data contains
50  * a series of parts. Each part is expected to contain a content-disposition
51  * header where the value is "form-data" and a name attribute specifies
52  * the field name within the form, e.g., 'content-disposition: form-data;
53  * name="xxxxx"', where xxxxx is the field name corresponding to that field.
54  * Field names originally in non-ASCII character sets may be encoded using
55  * the method outlined in RFC 1522.
56  * </blockquote>
57  * </p>
58  * <p>This entity is designed to be used in conjunction with the
59  * {@link org.apache.commons.httpclient.methods.PostMethod post method} to provide
60  * multipart posts. Example usage:</p>
61  * <pre>
62  * File f = new File("/path/fileToUpload.txt");
63  * PostMethod filePost = new PostMethod("http://host/some_path");
64  * Part[] parts = {
65  * new StringPart("param_name", "value"),
66  * new FilePart(f.getName(), f)
67  * };
68  * filePost.setRequestEntity(
69  * new MultipartRequestEntity(parts, filePost.getParams())
70  * );
71  * HttpClient client = new HttpClient();
72  * int status = client.executeMethod(filePost);
73  * </pre>
74  *
75  * @since 3.0
76  */
77 public class MultipartRequestEntity implements RequestEntity {
78
79     private static final Log log = LogFactory.getLog(MultipartRequestEntity.class);
80     
81     /** The Content-Type for multipart/form-data. */
82     private static final String JavaDoc MULTIPART_FORM_CONTENT_TYPE = "multipart/form-data";
83     
84     /**
85      * The pool of ASCII chars to be used for generating a multipart boundary.
86      */
87     private static byte[] MULTIPART_CHARS = EncodingUtil.getAsciiBytes(
88         "-_1234567890abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ");
89     
90     /**
91      * Generates a random multipart boundary string.
92      * @return
93      */
94     private static byte[] generateMultipartBoundary() {
95         Random JavaDoc rand = new Random JavaDoc();
96         byte[] bytes = new byte[rand.nextInt(11) + 30]; // a random size from 30 to 40
97 for (int i = 0; i < bytes.length; i++) {
98             bytes[i] = MULTIPART_CHARS[rand.nextInt(MULTIPART_CHARS.length)];
99         }
100         return bytes;
101     }
102     
103     /** The MIME parts as set by the constructor */
104     protected Part[] parts;
105     
106     private byte[] multipartBoundary;
107     
108     private HttpMethodParams params;
109     
110     /**
111      * Creates a new multipart entity containing the given parts.
112      * @param parts The parts to include.
113      * @param params The params of the HttpMethod using this entity.
114      */
115     public MultipartRequestEntity(Part[] parts, HttpMethodParams params) {
116         if (parts == null) {
117             throw new IllegalArgumentException JavaDoc("parts cannot be null");
118         }
119         if (params == null) {
120             throw new IllegalArgumentException JavaDoc("params cannot be null");
121         }
122         this.parts = parts;
123         this.params = params;
124     }
125
126     /**
127      * Returns the MIME boundary string that is used to demarcate boundaries of
128      * this part. The first call to this method will implicitly create a new
129      * boundary string. To create a boundary string first the
130      * HttpMethodParams.MULTIPART_BOUNDARY parameter is considered. Otherwise
131      * a random one is generated.
132      *
133      * @return The boundary string of this entity in ASCII encoding.
134      */
135     protected byte[] getMultipartBoundary() {
136         if (multipartBoundary == null) {
137             String JavaDoc temp = (String JavaDoc) params.getParameter(HttpMethodParams.MULTIPART_BOUNDARY);
138             if (temp != null) {
139                 multipartBoundary = EncodingUtil.getAsciiBytes(temp);
140             } else {
141                 multipartBoundary = generateMultipartBoundary();
142             }
143         }
144         return multipartBoundary;
145     }
146
147     /**
148      * Returns <code>true</code> if all parts are repeatable, <code>false</code> otherwise.
149      * @see org.apache.commons.httpclient.methods.RequestEntity#isRepeatable()
150      */
151     public boolean isRepeatable() {
152         for (int i = 0; i < parts.length; i++) {
153             if (!parts[i].isRepeatable()) {
154                 return false;
155             }
156         }
157         return true;
158     }
159
160     /* (non-Javadoc)
161      * @see org.apache.commons.httpclient.methods.RequestEntity#writeRequest(java.io.OutputStream)
162      */
163     public void writeRequest(OutputStream JavaDoc out) throws IOException JavaDoc {
164         Part.sendParts(out, parts, getMultipartBoundary());
165     }
166
167     /* (non-Javadoc)
168      * @see org.apache.commons.httpclient.methods.RequestEntity#getContentLength()
169      */
170     public long getContentLength() {
171         try {
172             return Part.getLengthOfParts(parts, getMultipartBoundary());
173         } catch (Exception JavaDoc e) {
174             log.error("An exception occurred while getting the length of the parts", e);
175             return 0;
176         }
177     }
178
179     /* (non-Javadoc)
180      * @see org.apache.commons.httpclient.methods.RequestEntity#getContentType()
181      */
182     public String JavaDoc getContentType() {
183         StringBuffer JavaDoc buffer = new StringBuffer JavaDoc(MULTIPART_FORM_CONTENT_TYPE);
184         buffer.append("; boundary=");
185         buffer.append(EncodingUtil.getAsciiString(getMultipartBoundary()));
186         return buffer.toString();
187     }
188
189 }
190
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