1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 *
19 */
20
21 package org.apache.directory.server.dns.util;
22
23
24 import java.util.HashMap;
25 import java.util.Map;
26
27 import org.apache.directory.server.i18n.I18n;
28
29
30 /**
31 * A map to easily get the actual Enum instance from it's value as seen in the
32 * <a href="http://www.javaspecialists.co.za/archive/newsletter.do?issue=113">
33 * The JavaSpecialists newsletter</a>.
34 *
35 * @param <K>
36 * @param <E>
37 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
38 */
39 public class ReverseEnumMap<K, E extends Enum<E> & EnumConverter<K>>
40 {
41 private Map<K, E> reverseMap = new HashMap<>();
42
43
44 /**
45 * Creates a new instance of ReverseEnumMap.
46 *
47 * @param enumType
48 */
49 public ReverseEnumMap( Class<E> enumType )
50 {
51 for ( E e : enumType.getEnumConstants() )
52 {
53 reverseMap.put( e.convert(), e );
54 }
55 }
56
57
58 /**
59 * Return the enum given an ordinal value.
60 *
61 * @param value
62 * @return The enum.
63 */
64 public E get( K value )
65 {
66 E e = reverseMap.get( value );
67 if ( e == null )
68 {
69 throw new IllegalArgumentException( I18n.err( I18n.ERR_650, value ) );
70 }
71 return e;
72 }
73 }