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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.client.methods;
28  
29  import java.io.IOException;
30  import java.nio.ByteBuffer;
31  
32  import org.apache.http.HttpEntity;
33  import org.apache.http.entity.ContentType;
34  import org.apache.http.nio.ContentDecoder;
35  import org.apache.http.nio.IOControl;
36  import org.apache.http.nio.protocol.AbstractAsyncResponseConsumer;
37  import org.apache.http.util.Asserts;
38  
39  /**
40   * {@link org.apache.http.nio.protocol.HttpAsyncResponseConsumer} implementation that
41   * provides convenience methods for processing of binary content entities enclosed
42   * in an HTTP response.
43   *
44   * @since 4.0
45   */
46  public abstract class AsyncByteConsumer<T> extends AbstractAsyncResponseConsumer<T> {
47  
48      private final ByteBuffer bbuf;
49  
50      public AsyncByteConsumer(final int bufSize) {
51          super();
52          this.bbuf = ByteBuffer.allocate(bufSize);
53      }
54  
55      public AsyncByteConsumer() {
56          this(8 * 1024);
57      }
58  
59      /**
60       * Invoked to process a {@link ByteBuffer chunk} of content.
61       * The {@link IOControl} interface can be used to suspend input events
62       * if the consumer is temporarily unable to consume more content.
63       *
64       * @param buf chunk of content.
65       * @param ioctrl I/O control of the underlying connection.
66       * @throws IOException in case of an I/O error
67       */
68      protected abstract void onByteReceived(
69              ByteBuffer buf, IOControl ioctrl) throws IOException;
70  
71      @Override
72      protected final void onEntityEnclosed(
73              final HttpEntity entity, final ContentType contentType) throws IOException {
74      }
75  
76      @Override
77      protected final void onContentReceived(
78              final ContentDecoder decoder, final IOControl ioctrl) throws IOException {
79          Asserts.notNull(this.bbuf, "Byte buffer");
80          final int bytesRead = decoder.read(this.bbuf);
81          if (bytesRead <= 0) {
82              return;
83          }
84          this.bbuf.flip();
85          onByteReceived(this.bbuf, ioctrl);
86          this.bbuf.clear();
87      }
88  
89      @Override
90      protected void releaseResources() {
91      }
92  
93  }