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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  
36  /**
37   * A generic streamed, non-repeatable entity that obtains its content
38   * from an {@link InputStream}.
39   *
40   * @since 4.0
41   */
42  @NotThreadSafe
43  public class BasicHttpEntity extends AbstractHttpEntity {
44  
45      private InputStream content;
46      private long length;
47  
48      /**
49       * Creates a new basic entity.
50       * The content is initially missing, the content length
51       * is set to a negative number.
52       */
53      public BasicHttpEntity() {
54          super();
55          this.length = -1;
56      }
57  
58      public long getContentLength() {
59          return this.length;
60      }
61  
62      /**
63       * Obtains the content, once only.
64       *
65       * @return  the content, if this is the first call to this method
66       *          since {@link #setContent setContent} has been called
67       *
68       * @throws IllegalStateException
69       *          if the content has not been provided
70       */
71      public InputStream getContent() throws IllegalStateException {
72          if (this.content == null) {
73              throw new IllegalStateException("Content has not been provided");
74          }
75          return this.content;
76  
77      }
78  
79      /**
80       * Tells that this entity is not repeatable.
81       *
82       * @return <code>false</code>
83       */
84      public boolean isRepeatable() {
85          return false;
86      }
87  
88      /**
89       * Specifies the length of the content.
90       *
91       * @param len       the number of bytes in the content, or
92       *                  a negative number to indicate an unknown length
93       */
94      public void setContentLength(long len) {
95          this.length = len;
96      }
97  
98      /**
99       * Specifies the content.
100      *
101      * @param instream          the stream to return with the next call to
102      *                          {@link #getContent getContent}
103      */
104     public void setContent(final InputStream instream) {
105         this.content = instream;
106     }
107 
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         InputStream instream = getContent();
113         try {
114             int l;
115             byte[] tmp = new byte[2048];
116             while ((l = instream.read(tmp)) != -1) {
117                 outstream.write(tmp, 0, l);
118             }
119         } finally {
120             instream.close();
121         }
122     }
123 
124     public boolean isStreaming() {
125         return this.content != null;
126     }
127 
128     /**
129      * Closes the content InputStream.
130      *
131      * @deprecated (4.1) Either use {@link #getContent()} and call {@link java.io.InputStream#close()} on that;
132      * otherwise call {@link #writeTo(OutputStream)} which is required to free the resources.
133      */
134     @Deprecated
135     @Override
136     public void consumeContent() throws IOException {
137         if (content != null) {
138             content.close(); // reads to the end of the entity
139         }
140     }
141 
142 }