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.discovery.resource.names;
18
19 import java.util.HashMap;
20 import java.util.Map;
21
22 import org.apache.commons.discovery.ResourceNameDiscover;
23 import org.apache.commons.discovery.ResourceNameIterator;
24 import org.apache.commons.discovery.tools.ManagedProperties;
25 import org.apache.commons.logging.Log;
26 import org.apache.commons.logging.LogFactory;
27
28 /**
29 * Recover resource name from Managed Properties,
30 * using OLD property names.
31 *
32 * This class maintains a mapping between old names and
33 * (new) the class names they represent. The discovery
34 * mechanism uses the class names as property names.
35 *
36 * @see org.apache.commons.discovery.tools.ManagedProperties
37 */
38 public class DiscoverNamesInAlternateManagedProperties
39 extends ResourceNameDiscoverImpl
40 implements ResourceNameDiscover {
41
42 private static Log log = LogFactory.getLog(DiscoverNamesInAlternateManagedProperties.class);
43
44 /**
45 * Sets the {@code Log} for this class.
46 *
47 * @param _log This class {@code Log}
48 * @deprecated This method is not thread-safe
49 */
50 @Deprecated
51 public static void setLog(Log _log) {
52 log = _log;
53 }
54
55 private final Map<String, String> mapping = new HashMap<String, String>();
56
57 /**
58 * Construct a new resource discoverer.
59 */
60 public DiscoverNamesInAlternateManagedProperties() {
61 }
62
63 /**
64 * Add a class name/property name mapping.
65 *
66 * @param className The class name
67 * @param propertyName The property name
68 */
69 public void addClassToPropertyNameMapping(String className, String propertyName) {
70 mapping.put(className, propertyName);
71 }
72
73 /**
74 * {@inheritDoc}
75 */
76 @Override
77 public ResourceNameIterator findResourceNames(final String resourceName) {
78 final String mappedName = mapping.get(resourceName);
79
80 if (log.isDebugEnabled()) {
81 if (mappedName == null) {
82 log.debug("find: resourceName='" + resourceName + "', no mapping");
83 } else {
84 log.debug("find: resourceName='" + resourceName + "', lookup property '" + mappedName + "'");
85 }
86 }
87
88 return new ResourceNameIterator() {
89 private String resource =
90 (mappedName == null) ? null : ManagedProperties.getProperty(mappedName);
91
92 public boolean hasNext() {
93 return resource != null;
94 }
95
96 public String nextResourceName() {
97 String element = resource;
98 resource = null;
99 return element;
100 }
101 };
102 }
103
104 }