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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.IOException;
31  import java.io.InputStream;
32  import java.io.OutputStream;
33  
34  import org.apache.http.annotation.NotThreadSafe;
35  import org.apache.http.util.Args;
36  
37  /**
38   * A streamed, non-repeatable entity that obtains its content from
39   * an {@link InputStream}.
40   *
41   * @since 4.0
42   */
43  @NotThreadSafe
44  public class InputStreamEntity extends AbstractHttpEntity {
45  
46      private final InputStream content;
47      private final long length;
48  
49      /**
50       * Creates an entity with an unknown length.
51       * Equivalent to {@code new InputStreamEntity(instream, -1)}.
52       *
53       * @param instream input stream
54       * @throws IllegalArgumentException if {@code instream} is {@code null}
55       * @since 4.3
56       */
57      public InputStreamEntity(final InputStream instream) {
58          this(instream, -1);
59      }
60  
61      /**
62       * Creates an entity with a specified content length.
63       *
64       * @param instream input stream
65       * @param length of the input stream, {@code -1} if unknown
66       * @throws IllegalArgumentException if {@code instream} is {@code null}
67       */
68      public InputStreamEntity(final InputStream instream, final long length) {
69          this(instream, length, null);
70      }
71  
72      /**
73       * Creates an entity with a content type and unknown length.
74       * Equivalent to {@code new InputStreamEntity(instream, -1, contentType)}.
75       *
76       * @param instream input stream
77       * @param contentType content type
78       * @throws IllegalArgumentException if {@code instream} is {@code null}
79       * @since 4.3
80       */
81      public InputStreamEntity(final InputStream instream, final ContentType contentType) {
82          this(instream, -1, contentType);
83      }
84  
85      /**
86       * @param instream input stream
87       * @param length of the input stream, {@code -1} if unknown
88       * @param contentType for specifying the {@code Content-Type} header, may be {@code null}
89       * @throws IllegalArgumentException if {@code instream} is {@code null}
90       * @since 4.2
91       */
92      public InputStreamEntity(final InputStream instream, final long length, final ContentType contentType) {
93          super();
94          this.content = Args.notNull(instream, "Source input stream");
95          this.length = length;
96          if (contentType != null) {
97              setContentType(contentType.toString());
98          }
99      }
100 
101     public boolean isRepeatable() {
102         return false;
103     }
104 
105     /**
106      * @return the content length or {@code -1} if unknown
107      */
108     public long getContentLength() {
109         return this.length;
110     }
111 
112     public InputStream getContent() throws IOException {
113         return this.content;
114     }
115 
116     /**
117      * Writes bytes from the {@code InputStream} this entity was constructed
118      * with to an {@code OutputStream}.  The content length
119      * determines how many bytes are written.  If the length is unknown ({@code -1}), the
120      * stream will be completely consumed (to the end of the stream).
121      *
122      */
123     public void writeTo(final OutputStream outstream) throws IOException {
124         Args.notNull(outstream, "Output stream");
125         final InputStream instream = this.content;
126         try {
127             final byte[] buffer = new byte[OUTPUT_BUFFER_SIZE];
128             int l;
129             if (this.length < 0) {
130                 // consume until EOF
131                 while ((l = instream.read(buffer)) != -1) {
132                     outstream.write(buffer, 0, l);
133                 }
134             } else {
135                 // consume no more than length
136                 long remaining = this.length;
137                 while (remaining > 0) {
138                     l = instream.read(buffer, 0, (int)Math.min(OUTPUT_BUFFER_SIZE, remaining));
139                     if (l == -1) {
140                         break;
141                     }
142                     outstream.write(buffer, 0, l);
143                     remaining -= l;
144                 }
145             }
146         } finally {
147             instream.close();
148         }
149     }
150 
151     public boolean isStreaming() {
152         return true;
153     }
154 
155 }