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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.logging.log4j.util;
18  
19  import java.util.Locale;
20  
21  /**
22   * <em>Consider this class private.</em>
23   * 
24   * <p>
25   * Helps convert English Strings to English Enum values.
26   * </p>
27   * <p>
28   * Enum name arguments are converted internally to upper case with the {@linkplain Locale#ENGLISH ENGLISH} locale to
29   * avoid problems on the Turkish locale. Do not use with Turkish enum values.
30   * </p>
31   */
32  public final class EnglishEnums {
33  
34      private EnglishEnums() {
35      }
36  
37      /**
38       * Returns the Result for the given string.
39       * <p>
40       * The {@code name} is converted internally to upper case with the {@linkplain Locale#ENGLISH ENGLISH} locale to
41       * avoid problems on the Turkish locale. Do not use with Turkish enum values.
42       * </p>
43       *
44       * @param enumType The Class of the enum.
45       * @param name The enum name, case-insensitive. If null, returns {@code defaultValue}.
46       * @param <T> The type of the enum.
47       * @return an enum value or null if {@code name} is null.
48       */
49      public static <T extends Enum<T>> T valueOf(final Class<T> enumType, final String name) {
50          return valueOf(enumType, name, null);
51      }
52  
53      /**
54       * Returns an enum value for the given string.
55       * <p>
56       * The {@code name} is converted internally to upper case with the {@linkplain Locale#ENGLISH ENGLISH} locale to
57       * avoid problems on the Turkish locale. Do not use with Turkish enum values.
58       * </p>
59       *
60       * @param name The enum name, case-insensitive. If null, returns {@code defaultValue}.
61       * @param enumType The Class of the enum.
62       * @param defaultValue the enum value to return if {@code name} is null.
63       * @param <T> The type of the enum.
64       * @return an enum value or {@code defaultValue} if {@code name} is null.
65       */
66      public static <T extends Enum<T>> T valueOf(final Class<T> enumType, final String name, final T defaultValue) {
67          return name == null ? defaultValue : Enum.valueOf(enumType, name.toUpperCase(Locale.ENGLISH));
68      }
69  
70  }