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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.configuration2.tree;
18  
19  import org.apache.commons.lang3.StringUtils;
20  
21  /**
22   * <p>
23   * An enumeration class with several pre-defined {@link NodeMatcher} implementations based on node names.
24   * </p>
25   * <p>
26   * Filtering nodes by their name is a typical use case. Therefore, some default implementations for typical filter
27   * algorithms are already provided. They are available as constants of this class. Because the algorithms are state-less
28   * these instances can be shared and accessed concurrently.
29   * </p>
30   *
31   * @since 2.0
32   */
33  public enum NodeNameMatchers implements NodeMatcher<String> {
34      /**
35       * A matcher for exact node name matches. This matcher returns <b>true</b> if and only if the name of the passed in node
36       * equals exactly the given criterion string.
37       */
38      EQUALS {
39          @Override
40          public <T> boolean matches(final T node, final NodeHandler<T> handler, final String criterion) {
41              return StringUtils.equals(criterion, handler.nodeName(node));
42          }
43      },
44  
45      /**
46       * A matcher for matches on node names which ignores case. For this matcher the names {@code node}, {@code NODE}, or
47       * {@code NodE} are all the same.
48       */
49      EQUALS_IGNORE_CASE {
50          @Override
51          public <T> boolean matches(final T node, final NodeHandler<T> handler, final String criterion) {
52              return StringUtils.equalsIgnoreCase(criterion, handler.nodeName(node));
53          }
54      }
55  }