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.entity;
29
30 import java.io.ByteArrayInputStream;
31 import java.io.IOException;
32 import java.io.InputStream;
33 import java.io.OutputStream;
34
35 import org.apache.http.HttpEntity;
36 import org.apache.http.annotation.NotThreadSafe;
37 import org.apache.http.util.EntityUtils;
38
39 /**
40 * A wrapping entity that buffers it content if necessary.
41 * The buffered entity is always repeatable.
42 * If the wrapped entity is repeatable itself, calls are passed through.
43 * If the wrapped entity is not repeatable, the content is read into a
44 * buffer once and provided from there as often as required.
45 *
46 * @since 4.0
47 */
48 @NotThreadSafe
49 public class BufferedHttpEntity extends HttpEntityWrapper {
50
51 private final byte[] buffer;
52
53 /**
54 * Creates a new buffered entity wrapper.
55 *
56 * @param entity the entity to wrap, not null
57 * @throws IllegalArgumentException if wrapped is null
58 */
59 public BufferedHttpEntity(final HttpEntity entity) throws IOException {
60 super(entity);
61 if (!entity.isRepeatable() || entity.getContentLength() < 0) {
62 this.buffer = EntityUtils.toByteArray(entity);
63 } else {
64 this.buffer = null;
65 }
66 }
67
68 @Override
69 public long getContentLength() {
70 if (this.buffer != null) {
71 return this.buffer.length;
72 } else {
73 return wrappedEntity.getContentLength();
74 }
75 }
76
77 @Override
78 public InputStream getContent() throws IOException {
79 if (this.buffer != null) {
80 return new ByteArrayInputStream(this.buffer);
81 } else {
82 return wrappedEntity.getContent();
83 }
84 }
85
86 /**
87 * Tells that this entity does not have to be chunked.
88 *
89 * @return <code>false</code>
90 */
91 @Override
92 public boolean isChunked() {
93 return (buffer == null) && wrappedEntity.isChunked();
94 }
95
96 /**
97 * Tells that this entity is repeatable.
98 *
99 * @return <code>true</code>
100 */
101 @Override
102 public boolean isRepeatable() {
103 return true;
104 }
105
106
107 @Override
108 public void writeTo(final OutputStream outstream) throws IOException {
109 if (outstream == null) {
110 throw new IllegalArgumentException("Output stream may not be null");
111 }
112 if (this.buffer != null) {
113 outstream.write(this.buffer);
114 } else {
115 wrappedEntity.writeTo(outstream);
116 }
117 }
118
119
120 // non-javadoc, see interface HttpEntity
121 @Override
122 public boolean isStreaming() {
123 return (buffer == null) && wrappedEntity.isStreaming();
124 }
125
126 } // class BufferedHttpEntity