1 /*
2 * Copyright 2012-2013 smartics, Kronseder & Reiner GmbH
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16 package de.smartics.properties.impl.config.ds;
17
18 import java.util.Iterator;
19 import java.util.Locale;
20 import java.util.ServiceLoader;
21 import java.util.concurrent.CopyOnWriteArrayList;
22
23 import javax.annotation.concurrent.ThreadSafe;
24
25 import de.smartics.properties.spi.config.ds.DataSourceConnector;
26 import de.smartics.util.lang.Arg;
27
28 /**
29 * Manager for connector implementations.
30 */
31 @ThreadSafe
32 public final class DataSourceProxyManager
33 {
34 // ********************************* Fields *********************************
35
36 // --- constants ------------------------------------------------------------
37
38 // --- members --------------------------------------------------------------
39
40 /**
41 * The registry of all registered connectors.
42 */
43 private static final CopyOnWriteArrayList<DataSourceConnector> REGISTRY =
44 new CopyOnWriteArrayList<DataSourceConnector>();
45
46 // ****************************** Initializer *******************************
47
48 static
49 {
50 final Iterator<DataSourceConnector> iterator =
51 ServiceLoader.load(DataSourceConnector.class).iterator();
52
53 while (iterator.hasNext())
54 {
55 final DataSourceConnector connector = iterator.next();
56 register(connector);
57 }
58 }
59
60 // ****************************** Constructors ******************************
61
62 private DataSourceProxyManager()
63 {
64 }
65
66 // ****************************** Inner Classes *****************************
67
68 // ********************************* Methods ********************************
69
70 // --- init -----------------------------------------------------------------
71
72 // --- get&set --------------------------------------------------------------
73
74 // --- business -------------------------------------------------------------
75
76 /**
77 * Registers the given connector. A connector implementation should call this
78 * method to make itself known to data source connector manager.
79 *
80 * @param connector the new connector to be registered.
81 */
82 public static void register(final DataSourceConnector connector)
83 {
84 synchronized (REGISTRY)
85 {
86 REGISTRY.addIfAbsent(Arg.checkNotNull("connector", connector));
87 }
88 }
89
90 /**
91 * Returns the first matching driver for a database identified by the given
92 * {@code id}.
93 *
94 * @param databaseId the identifier of the database.
95 * @return a connector to interface with the given data source.
96 * @throws IllegalStateException if no suitable connector has been registered.
97 */
98 public static DataSourceConnector getConnectorFor(final String databaseId)
99 throws IllegalStateException
100 {
101 final String normalized = databaseId.toLowerCase(Locale.ENGLISH);
102 for (final DataSourceConnector connector : REGISTRY)
103 {
104 if (connector.accepts(normalized))
105 {
106 return connector;
107 }
108 }
109
110 throw new IllegalStateException(String.format(
111 "No suitable connector found for '%s'.", normalized));
112 }
113
114 // --- object basics --------------------------------------------------------
115
116 }