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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  package org.apache.http.nio.protocol;
28  
29  import java.io.IOException;
30  
31  import org.apache.http.ContentTooLongException;
32  import org.apache.http.HttpEntity;
33  import org.apache.http.HttpResponse;
34  import org.apache.http.entity.ContentType;
35  import org.apache.http.nio.ContentDecoder;
36  import org.apache.http.nio.IOControl;
37  import org.apache.http.nio.entity.ContentBufferEntity;
38  import org.apache.http.nio.util.HeapByteBufferAllocator;
39  import org.apache.http.nio.util.SimpleInputBuffer;
40  import org.apache.http.protocol.HttpContext;
41  import org.apache.http.util.Asserts;
42  
43  /**
44   * Basic implementation of {@link HttpAsyncResponseConsumer}. Please note that
45   * this consumer buffers response content in memory and should be used for
46   * relatively small response messages.
47   *
48   * @since 4.2
49   */
50  public class BasicAsyncResponseConsumer extends AbstractAsyncResponseConsumer<HttpResponse> {
51  
52      private static final int MAX_INITIAL_BUFFER_SIZE = 256 * 1024;
53  
54      private volatile HttpResponse response;
55      private volatile SimpleInputBuffer buf;
56  
57      public BasicAsyncResponseConsumer() {
58          super();
59      }
60  
61      @Override
62      protected void onResponseReceived(final HttpResponse response) throws IOException {
63          this.response = response;
64      }
65  
66      @Override
67      protected void onEntityEnclosed(
68              final HttpEntity entity, final ContentType contentType) throws IOException {
69          long len = entity.getContentLength();
70          if (len > Integer.MAX_VALUE) {
71              throw new ContentTooLongException("Entity content is too long: " + len);
72          }
73          if (len < 0) {
74              len = 4096;
75          }
76          final int initialBufferSize = Math.min((int) len, MAX_INITIAL_BUFFER_SIZE);
77          this.buf = new SimpleInputBuffer(initialBufferSize, new HeapByteBufferAllocator());
78          this.response.setEntity(new ContentBufferEntity(entity, this.buf));
79      }
80  
81      @Override
82      protected void onContentReceived(
83              final ContentDecoder decoder, final IOControl ioctrl) throws IOException {
84          Asserts.notNull(this.buf, "Content buffer");
85          this.buf.consumeContent(decoder);
86      }
87  
88      @Override
89      protected void releaseResources() {
90          this.response = null;
91          this.buf = null;
92      }
93  
94      @Override
95      protected HttpResponse buildResult(final HttpContext context) {
96          return this.response;
97      }
98  
99  }