1 /*
2 * ====================================================================
3 * Licensed to the Apache Software Foundation (ASF) under one
4 * or more contributor license agreements. See the NOTICE file
5 * distributed with this work for additional information
6 * regarding copyright ownership. The ASF licenses this file
7 * to you under the Apache License, Version 2.0 (the
8 * "License"); you may not use this file except in compliance
9 * with the License. You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing,
14 * software distributed under the License is distributed on an
15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
16 * KIND, either express or implied. See the License for the
17 * specific language governing permissions and limitations
18 * under the License.
19 * ====================================================================
20 *
21 * This software consists of voluntary contributions made by many
22 * individuals on behalf of the Apache Software Foundation. For more
23 * information on the Apache Software Foundation, please see
24 * <http://www.apache.org/>.
25 *
26 */
27
28 package org.apache.http.impl.entity;
29
30 import java.io.IOException;
31
32 import org.apache.http.Header;
33 import org.apache.http.HttpEntity;
34 import org.apache.http.HttpException;
35 import org.apache.http.HttpMessage;
36 import org.apache.http.annotation.Immutable;
37 import org.apache.http.entity.BasicHttpEntity;
38 import org.apache.http.entity.ContentLengthStrategy;
39 import org.apache.http.impl.io.ChunkedInputStream;
40 import org.apache.http.impl.io.ContentLengthInputStream;
41 import org.apache.http.impl.io.IdentityInputStream;
42 import org.apache.http.io.SessionInputBuffer;
43 import org.apache.http.protocol.HTTP;
44
45 /**
46 * HTTP entity deserializer.
47 * <p>
48 * This entity deserializer supports "chunked" and "identitiy" transfer-coding
49 * and content length delimited content.
50 * <p>
51 * This class relies on a specific implementation of
52 * {@link ContentLengthStrategy} to determine the content length or transfer
53 * encoding of the entity.
54 * <p>
55 * This class generates an instance of {@link HttpEntity} based on
56 * properties of the message. The content of the entity will be decoded
57 * transparently for the consumer.
58 *
59 * @since 4.0
60 */
61 @Immutable // assuming injected dependencies are immutable
62 public class EntityDeserializer {
63
64 private final ContentLengthStrategy lenStrategy;
65
66 public EntityDeserializer(final ContentLengthStrategy lenStrategy) {
67 super();
68 if (lenStrategy == null) {
69 throw new IllegalArgumentException("Content length strategy may not be null");
70 }
71 this.lenStrategy = lenStrategy;
72 }
73
74 /**
75 * Creates a {@link BasicHttpEntity} based on properties of the given
76 * message. The content of the entity is created by wrapping
77 * {@link SessionInputBuffer} with a content decoder depending on the
78 * transfer mechanism used by the message.
79 * <p>
80 * This method is called by the public
81 * {@link #deserialize(SessionInputBuffer, HttpMessage)}.
82 *
83 * @param inbuffer the session input buffer.
84 * @param message the message.
85 * @return HTTP entity.
86 * @throws HttpException in case of HTTP protocol violation.
87 * @throws IOException in case of an I/O error.
88 */
89 protected BasicHttpEntity doDeserialize(
90 final SessionInputBuffer inbuffer,
91 final HttpMessage message) throws HttpException, IOException {
92 BasicHttpEntity entity = new BasicHttpEntity();
93
94 long len = this.lenStrategy.determineLength(message);
95 if (len == ContentLengthStrategy.CHUNKED) {
96 entity.setChunked(true);
97 entity.setContentLength(-1);
98 entity.setContent(new ChunkedInputStream(inbuffer));
99 } else if (len == ContentLengthStrategy.IDENTITY) {
100 entity.setChunked(false);
101 entity.setContentLength(-1);
102 entity.setContent(new IdentityInputStream(inbuffer));
103 } else {
104 entity.setChunked(false);
105 entity.setContentLength(len);
106 entity.setContent(new ContentLengthInputStream(inbuffer, len));
107 }
108
109 Header contentTypeHeader = message.getFirstHeader(HTTP.CONTENT_TYPE);
110 if (contentTypeHeader != null) {
111 entity.setContentType(contentTypeHeader);
112 }
113 Header contentEncodingHeader = message.getFirstHeader(HTTP.CONTENT_ENCODING);
114 if (contentEncodingHeader != null) {
115 entity.setContentEncoding(contentEncodingHeader);
116 }
117 return entity;
118 }
119
120 /**
121 * Creates an {@link HttpEntity} based on properties of the given message.
122 * The content of the entity is created by wrapping
123 * {@link SessionInputBuffer} with a content decoder depending on the
124 * transfer mechanism used by the message.
125 * <p>
126 * The content of the entity is NOT retrieved by this method.
127 *
128 * @param inbuffer the session input buffer.
129 * @param message the message.
130 * @return HTTP entity.
131 * @throws HttpException in case of HTTP protocol violation.
132 * @throws IOException in case of an I/O error.
133 */
134 public HttpEntity deserialize(
135 final SessionInputBuffer inbuffer,
136 final HttpMessage message) throws HttpException, IOException {
137 if (inbuffer == null) {
138 throw new IllegalArgumentException("Session input buffer may not be null");
139 }
140 if (message == null) {
141 throw new IllegalArgumentException("HTTP message may not be null");
142 }
143 return doDeserialize(inbuffer, message);
144 }
145
146 }