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1   /**
2    * This file Copyright (c) 2010-2011 Magnolia International
3    * Ltd.  (http://www.magnolia-cms.com). All rights reserved.
4    *
5    *
6    * This file is dual-licensed under both the Magnolia
7    * Network Agreement and the GNU General Public License.
8    * You may elect to use one or the other of these licenses.
9    *
10   * This file is distributed in the hope that it will be
11   * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
12   * implied warranty of MERCHANTABILITY or FITNESS FOR A
13   * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
14   * Redistribution, except as permitted by whichever of the GPL
15   * or MNA you select, is prohibited.
16   *
17   * 1. For the GPL license (GPL), you can redistribute and/or
18   * modify this file under the terms of the GNU General
19   * Public License, Version 3, as published by the Free Software
20   * Foundation.  You should have received a copy of the GNU
21   * General Public License, Version 3 along with this program;
22   * if not, write to the Free Software Foundation, Inc., 51
23   * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
24   *
25   * 2. For the Magnolia Network Agreement (MNA), this file
26   * and the accompanying materials are made available under the
27   * terms of the MNA which accompanies this distribution, and
28   * is available at http://www.magnolia-cms.com/mna.html
29   *
30   * Any modifications to this file must keep this entire header
31   * intact.
32   *
33   */
34  package info.magnolia.module.blossom.multipart;
35  
36  import java.lang.reflect.InvocationTargetException;
37  import java.lang.reflect.Method;
38  import java.util.Map;
39  import javax.servlet.http.HttpServletRequest;
40  
41  import org.springframework.util.Assert;
42  import org.springframework.web.multipart.MultipartFile;
43  import org.springframework.web.multipart.support.AbstractMultipartHttpServletRequest;
44  
45  /**
46   * As of version 3.0.0 Spring supports multiple multipart files with the same name. This changed the API introducing
47   * an incompatibility with implementations for earlier versions. This class uses reflection to use either the old API
48   * or the new API. It's used as a replacement for AbstractMultipartHttpServletRequest. The change was introduced with
49   * https://jira.springframework.org/browse/SPR-2784.
50   *
51   * @see org.springframework.web.multipart.MultipartRequest
52   * @see org.springframework.web.multipart.support.AbstractMultipartHttpServletRequest
53   * @since 1.2
54   */
55  public abstract class CompatibleAbstractMultipartHttpServletRequest extends AbstractMultipartHttpServletRequest {
56  
57      private static Method setter;
58      private static Class<?> multiValueType;
59      private static Method populateMethod;
60  
61      static {
62          setter = getDeclaredMethodIfAvailable(AbstractMultipartHttpServletRequest.class, "setMultipartFiles", Map.class);
63          if (setter == null) {
64              try {
65                  multiValueType = Class.forName("org.springframework.util.LinkedMultiValueMap");
66                  populateMethod = getDeclaredMethod(multiValueType, "setAll", Map.class);
67                  setter = getDeclaredMethod(AbstractMultipartHttpServletRequest.class, "setMultipartFiles", Class.forName("org.springframework.util.MultiValueMap"));
68              } catch (ClassNotFoundException e) {
69                  // One of the necessary classes are not available
70              } catch (NoSuchMethodException e) {
71                  // The Spring 3+ setter is not available
72              }
73          }
74      }
75  
76      protected CompatibleAbstractMultipartHttpServletRequest(HttpServletRequest request) {
77          super(request);
78      }
79  
80      protected void setSingleValueMultipartFiles(Map<String, MultipartFile> multipartFiles) throws InvocationTargetException, InstantiationException, IllegalAccessException {
81          Assert.notNull(setter, "No usable method found for setting multipartFiles in AbstractMultipartHttpServletRequest");
82          setter.invoke(this, convertMapIfNecessary(multipartFiles));
83      }
84  
85      private Object convertMapIfNecessary(Map<String, MultipartFile> multipartFiles) throws IllegalAccessException, InstantiationException, InvocationTargetException {
86  
87          // The earlier Spring 2.5.x setter is available
88          if (multiValueType == null) {
89              return multipartFiles;
90          }
91  
92          // Repackage the map in a MultiValueMap
93          Object multiValueMap = multiValueType.newInstance();
94          populateMethod.invoke(multiValueMap, multipartFiles);
95          return multiValueMap;
96      }
97  
98      private static Method getDeclaredMethodIfAvailable(Class<?> clazz, String name, Class... parameterTypes) {
99          try {
100             return getDeclaredMethod(clazz, name, parameterTypes);
101         } catch (NoSuchMethodException e) {
102             return null;
103         }
104     }
105 
106     private static Method getDeclaredMethod(Class<?> clazz, String name, Class... parameterTypes) throws NoSuchMethodException {
107         return clazz.getDeclaredMethod(name, parameterTypes);
108     }
109 }