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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package org.apache.commons.vfs2;
18  
19  import java.util.Arrays;
20  import java.util.Collection;
21  import java.util.HashSet;
22  import java.util.Set;
23  
24  /**
25   * A {@link FileSelector} that selects based on file extensions.
26   * <p>
27   * The extension comparison is case insensitive.
28   * </p>
29   * <p>
30   * The selector makes a copy of a given Collection or array. Changing the object passed in the constructors will not
31   * affect the selector.
32   * </p>
33   *
34   * @since 2.1
35   */
36  public class FileExtensionSelector implements FileSelector {
37  
38      /**
39       * The extensions to select.
40       */
41      private final Set<String> extensions = new HashSet<>();
42  
43      /**
44       * Creates a new selector for the given extensions.
45       *
46       * @param extensions The extensions to be included by this selector.
47       */
48      public FileExtensionSelector(final Collection<String> extensions) {
49          if (extensions != null) {
50              this.extensions.addAll(extensions);
51          }
52      }
53  
54      /**
55       * Creates a new selector for the given extensions.
56       *
57       * @param extensions The extensions to be included by this selector.
58       */
59      public FileExtensionSelector(final String... extensions) {
60          if (extensions != null) {
61              this.extensions.addAll(Arrays.asList(extensions));
62          }
63      }
64  
65      /**
66       * Determines if a file or folder should be selected.
67       *
68       * @param fileInfo The file selection information.
69       * @return true if the file should be selected, false otherwise.
70       */
71      @Override
72      public boolean includeFile(final FileSelectInfo fileInfo) throws Exception {
73          for (final String extension : this.extensions) {
74              if (fileInfo.getFile().getName().getExtension().equalsIgnoreCase(extension)) {
75                  return true;
76              }
77          }
78          return false;
79      }
80  
81      /**
82       * Determines whether a folder should be traversed.
83       *
84       * @param fileInfo The file selection information.
85       * @return true if descendants should be traversed, fase otherwise.
86       */
87      @Override
88      public boolean traverseDescendents(final FileSelectInfo fileInfo) throws Exception {
89          return true;
90      }
91  }