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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.client.utils;
28  
29  import java.io.IOException;
30  
31  import org.apache.http.HttpEntity;
32  import org.apache.http.HttpResponse;
33  import org.apache.http.client.HttpClient;
34  import org.apache.http.util.EntityUtils;
35  
36  /**
37   * Static helpers for dealing with {@link HttpResponse}s and {@link HttpClient}s.
38   * 
39   * @since 4.2
40   */
41  public class HttpClientUtils {
42  
43      private HttpClientUtils() {
44      }
45  
46      /**
47       * Unconditionally close a response.
48       * <p>
49       * Example Code:
50       * 
51       * <pre>
52       * HttpResponse httpResponse = null;
53       * try {
54       *     httpResponse = httpClient.execute(httpGet);
55       * } catch (Exception e) {
56       *     // error handling
57       * } finally {
58       *     HttpClientUtils.closeQuietly(httpResponse);
59       * }
60       * </pre>
61       * 
62       * @param response
63       *            the HttpResponse to release resources, may be null or already
64       *            closed.
65       * 
66       * @since 4.2
67       */
68      public static void closeQuietly(final HttpResponse response) {
69          if (response != null) {
70              HttpEntity entity = response.getEntity();
71              if (entity != null) {
72                  try {
73                      EntityUtils.consume(entity);
74                  } catch (final IOException ex) {
75                  }
76              }
77          }
78      }
79  
80      /**
81       * Unconditionally close a httpClient. Shuts down the underlying connection
82       * manager and releases the resources.
83       * <p>
84       * Example Code:
85       * 
86       * <pre>
87       * HttpClient httpClient = null;
88       * try {
89       *   httpClient = new DefaultHttpClient(...);
90       * } catch (Exception e) {
91       *   // error handling
92       * } finally {
93       *   HttpClientUtils.closeQuietly(httpClient);
94       * }
95       * </pre>
96       * 
97       * @param httpClient
98       *            the HttpClient to close, may be null or already closed.
99       * @since 4.2
100      */
101     public static void closeQuietly(final HttpClient httpClient) {
102         if (httpClient != null) {
103             httpClient.getConnectionManager().shutdown();
104         }
105     }
106 
107 }