1 /***
2 * Redistribution and use of this software and associated documentation
3 * ("Software"), with or without modification, are permitted provided
4 * that the following conditions are met:
5 *
6 * 1. Redistributions of source code must retain copyright
7 * statements and notices. Redistributions must also contain a
8 * copy of this document.
9 *
10 * 2. Redistributions in binary form must reproduce the
11 * above copyright notice, this list of conditions and the
12 * following disclaimer in the documentation and/or other
13 * materials provided with the distribution.
14 *
15 * 3. The name "Exolab" must not be used to endorse or promote
16 * products derived from this Software without prior written
17 * permission of Exoffice Technologies. For written permission,
18 * please contact info@exolab.org.
19 *
20 * 4. Products derived from this Software may not be called "Exolab"
21 * nor may "Exolab" appear in their names without prior written
22 * permission of Exoffice Technologies. Exolab is a registered
23 * trademark of Exoffice Technologies.
24 *
25 * 5. Due credit should be given to the Exolab Project
26 * (http://www.exolab.org/).
27 *
28 * THIS SOFTWARE IS PROVIDED BY EXOFFICE TECHNOLOGIES AND CONTRIBUTORS
29 * ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
30 * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
31 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
32 * EXOFFICE TECHNOLOGIES OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
33 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
34 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
35 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
37 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
38 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
39 * OF THE POSSIBILITY OF SUCH DAMAGE.
40 *
41 * Copyright 2001-2004 (C) Exoffice Technologies Inc. All Rights Reserved.
42 *
43 * $Id: DatabaseService.java,v 1.4 2006/02/23 11:17:39 tanderson Exp $
44 */
45 package org.exolab.jms.persistence;
46
47 import java.sql.Connection;
48 import java.sql.SQLException;
49
50 import org.apache.commons.logging.Log;
51 import org.apache.commons.logging.LogFactory;
52 import org.exolab.jms.common.threads.ThreadListener;
53 import org.exolab.jms.config.Configuration;
54 import org.exolab.jms.config.DatabaseConfiguration;
55 import org.exolab.jms.config.RdbmsDatabaseConfiguration;
56 import org.exolab.jms.service.Service;
57 import org.exolab.jms.service.ServiceException;
58 import org.exolab.jms.service.ServiceThreadListener;
59
60
61 /***
62 * The DatabaseService is used for managing the persistence aspect of this
63 * project.
64 *
65 * @author <a href="mailto:jima@comware.com.au">Jim Alateras</a>
66 * @version $Revision: 1.4 $ $Date: 2006/02/23 11:17:39 $
67 */
68 public class DatabaseService extends Service {
69
70 /***
71 * The configuration.
72 */
73 private final DatabaseConfiguration _config;
74
75 /***
76 * The persistence adapter.
77 */
78 private PersistenceAdapter _adapter;
79
80 /***
81 * Thread listener.
82 */
83 private ServiceThreadListener _listener;
84
85 /***
86 * State monitor.
87 */
88 private ThreadListener _monitor;
89
90 /***
91 * The service state associated with the current thread.
92 */
93 private static final ThreadLocal _state = new ThreadLocal();
94
95 /***
96 * The logger.
97 */
98 private static final Log _log = LogFactory.getLog(DatabaseService.class);
99
100
101 /***
102 * Construct a new <code>DatabaseService</code>.
103 *
104 * @param config the configuration
105 */
106 public DatabaseService(Configuration config) {
107 super("DatabaseService");
108 _config = config.getDatabaseConfiguration();
109 _monitor = new Monitor();
110 }
111
112 /***
113 * Sets the service thread listener.
114 *
115 * @param listener the service thread listener
116 */
117 public void setServiceThreadListener(ServiceThreadListener listener) {
118 _listener = listener;
119 }
120
121 /***
122 * Returns the database service associated with the current thread.
123 *
124 * @return the database service associated with the current thread
125 * @throws PersistenceException if no instance is registered
126 */
127 public static DatabaseService getInstance() throws PersistenceException {
128 State state = (State) _state.get();
129 if (state == null) {
130 throw new PersistenceException("No DatabaseService registered");
131 }
132 return state.getInstance();
133 }
134
135 /***
136 * Returns the {@link PersistenceAdapter} created by this service.
137 *
138 * @return the persistence adapter
139 */
140 public PersistenceAdapter getAdapter() {
141 return _adapter;
142 }
143
144 /***
145 * Begin a transaction.
146 *
147 * @throws PersistenceException if a transaction cannot be started
148 */
149 public void begin() throws PersistenceException {
150 State state = (State) _state.get();
151 if (state == null) {
152 _state.set(new State());
153 } else {
154 if (state.getInstance() != this) {
155 throw new PersistenceException(
156 "State not associated with current service");
157 }
158 _log.error("Transaction in progress, allocated at ", state.STACK);
159 throw new PersistenceException("Transaction already in progress");
160
161 }
162 }
163
164 /***
165 * Returns the connection associated with the current thread.
166 *
167 * @return the connection associated with the current thread
168 * @throws PersistenceException if no connection is associated
169 */
170 public Connection getConnection() throws PersistenceException {
171 State state = getState();
172 if (state.getConnection() == null) {
173 state.setConnection(_adapter.getConnection());
174 }
175 return state.getConnection();
176 }
177
178 /***
179 * Commit the current transaction.
180 *
181 * @throws PersistenceException if the transaction can't be committed
182 */
183 public void commit() throws PersistenceException {
184 State state = getState();
185 Connection connection = state.getConnection();
186 try {
187 if (connection != null) {
188 connection.commit();
189 }
190 } catch (SQLException exception) {
191 throw new PersistenceException("Failed to commit", exception);
192 } finally {
193 SQLHelper.close(connection);
194 _state.set(null);
195 }
196 }
197
198 /***
199 * Rollback the current transaction.
200 *
201 * @throws PersistenceException if the transaction can't be rolled back
202 */
203 public void rollback() throws PersistenceException {
204 State state = getState();
205 Connection connection = state.getConnection();
206 try {
207 if (connection != null) {
208 connection.rollback();
209 }
210 } catch (SQLException exception) {
211 throw new PersistenceException("Failed to rollback", exception);
212 } finally {
213 SQLHelper.close(connection);
214 _state.set(null);
215 }
216 }
217
218 /***
219 * Determines if a transaction is in progress.
220 *
221 * @return <code>true</code> if a transaction is in progress; otherwise
222 * <code>false</code>
223 */
224 public boolean isTransacted() {
225 return (_state.get() != null);
226 }
227
228 /***
229 * Start the service.
230 *
231 * @throws ServiceException if the service fails to start
232 */
233 protected void doStart() throws ServiceException {
234 if (_listener != null) {
235 _listener.addThreadListener(_monitor);
236 } else {
237 _log.info("Not monitoring service threads");
238 }
239
240 _adapter = createAdapter(_config);
241
242
243 try {
244 begin();
245 Connection connection = getConnection();
246
247 getAdapter().removeExpiredMessages(connection);
248 _log.info("Removed expired messages.");
249 commit();
250 } catch (PersistenceException exception) {
251 try {
252 rollback();
253 } catch (PersistenceException ignore) {
254
255 }
256 throw exception;
257 } catch (Exception exception) {
258
259 throw new ServiceException("Failed to start the DatabaseService",
260 exception);
261 }
262 }
263
264 /***
265 * Stop the service.
266 *
267 * @throws ServiceException if the service fails to stop
268 */
269 protected void doStop() throws ServiceException {
270 if (_listener != null) {
271 _listener.removeThreadListener(_monitor);
272 }
273 _adapter.close();
274 _state.set(null);
275 }
276
277 /***
278 * Returns the current transaction state.
279 *
280 * @return the current transaction state
281 * @throws PersistenceException if there is no current transaction
282 */
283 private State getState() throws PersistenceException {
284 State state = (State) _state.get();
285 if (state == null) {
286 throw new PersistenceException("No transaction in progress");
287 }
288 if (state.getInstance() != this) {
289 throw new PersistenceException(
290 "State not associated with current service");
291 }
292 return state;
293 }
294
295 /***
296 * Create an instance of an persistence adapter using the specified database
297 * configuration.
298 *
299 * @param dbConfig database configuration
300 * @return the created adapter
301 * @throws PersistenceException if the adapter cant be created
302 */
303 private PersistenceAdapter createAdapter(
304 DatabaseConfiguration dbConfig) throws PersistenceException {
305 PersistenceAdapter adapter = null;
306 RdbmsDatabaseConfiguration
307 config = dbConfig.getRdbmsDatabaseConfiguration();
308
309 _log.info("Creating RdbmsAdapter for "
310 + config.getDriver());
311 adapter = new RDBMSAdapter(dbConfig, config.getDriver(),
312 config.getUrl(),
313 config.getUser(),
314 config.getPassword());
315
316 return adapter;
317 }
318
319 class State {
320
321 public final Exception STACK = new Exception();
322
323 private Connection _connection;
324
325 public DatabaseService getInstance() {
326 return DatabaseService.this;
327 }
328
329 public Connection getConnection() {
330 return _connection;
331 }
332
333 public void setConnection(Connection connection) {
334 _connection = connection;
335 }
336 }
337
338 static class Monitor implements ThreadListener {
339
340 public void begin(Runnable command) {
341 }
342
343 public void end(Runnable command) {
344 State state = (State) _state.get();
345 if (state != null) {
346 _state.set(null);
347 _log.error("Transaction not finished by " + command
348 + ". Allocated at ", state.STACK);
349 SQLHelper.close(state.getConnection());
350 }
351 }
352
353 }
354
355 }
356
357