Source Code Cross Referenced for FileBacking.java in  » EJB-Server-resin-3.1.5 » resin » com » caucho » server » cluster » Java Source Code / Java DocumentationJava Source Code and Java Documentation

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Java Source Code / Java Documentation » EJB Server resin 3.1.5 » resin » com.caucho.server.cluster 
Source Cross Referenced  Class Diagram Java Document (Java Doc) 


001:        /*
002:         * Copyright (c) 1998-2008 Caucho Technology -- all rights reserved
003:         *
004:         * This file is part of Resin(R) Open Source
005:         *
006:         * Each copy or derived work must preserve the copyright notice and this
007:         * notice unmodified.
008:         *
009:         * Resin Open Source is free software; you can redistribute it and/or modify
010:         * it under the terms of the GNU General Public License as published by
011:         * the Free Software Foundation; either version 2 of the License, or
012:         * (at your option) any later version.
013:         *
014:         * Resin Open Source is distributed in the hope that it will be useful,
015:         * but WITHOUT ANY WARRANTY; without even the implied warranty of
016:         * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, or any warranty
017:         * of NON-INFRINGEMENT.  See the GNU General Public License for more
018:         * details.
019:         *
020:         * You should have received a copy of the GNU General Public License
021:         * along with Resin Open Source; if not, write to the
022:         *
023:         *   Free Software Foundation, Inc.
024:         *   59 Temple Place, Suite 330
025:         *   Boston, MA 02111-1307  USA
026:         *
027:         * @author Scott Ferguson
028:         */
029:
030:        package com.caucho.server.cluster;
031:
032:        import com.caucho.config.ConfigException;
033:        import com.caucho.db.jdbc.DataSourceImpl;
034:        import com.caucho.util.Alarm;
035:        import com.caucho.util.FreeList;
036:        import com.caucho.util.L10N;
037:        import com.caucho.util.Log;
038:        import com.caucho.vfs.Path;
039:        import com.caucho.vfs.ReadStream;
040:        import com.caucho.vfs.WriteStream;
041:
042:        import javax.sql.DataSource;
043:        import java.io.IOException;
044:        import java.io.InputStream;
045:        import java.sql.Connection;
046:        import java.sql.PreparedStatement;
047:        import java.sql.ResultSet;
048:        import java.sql.SQLException;
049:        import java.sql.Statement;
050:        import java.util.logging.Level;
051:        import java.util.logging.Logger;
052:
053:        /**
054:         * Manages the backing for the file store.
055:         */
056:        public class FileBacking {
057:            private static final L10N L = new L10N(FileBacking.class);
058:            private static final Logger log = Logger
059:                    .getLogger(FileBacking.class.getName());
060:
061:            private FreeList<ClusterConnection> _freeConn = new FreeList<ClusterConnection>(
062:                    32);
063:
064:            private String _name;
065:
066:            private Path _path;
067:
068:            private DataSource _dataSource;
069:
070:            private String _tableName;
071:            private String _loadQuery;
072:            private String _updateQuery;
073:            private String _accessQuery;
074:            private String _setExpiresQuery;
075:            private String _insertQuery;
076:            private String _invalidateQuery;
077:            private String _timeoutQuery;
078:            private String _dumpQuery;
079:            private String _countQuery;
080:
081:            public FileBacking() {
082:            }
083:
084:            public FileBacking(String name) {
085:                _name = name;
086:            }
087:
088:            /**
089:             * Returns the path to the directory.
090:             */
091:            public Path getPath() {
092:                return _path;
093:            }
094:
095:            /**
096:             * Sets the path to the saved file.
097:             */
098:            public void setPath(Path path) {
099:                _path = path;
100:            }
101:
102:            /**
103:             * Sets the table name
104:             */
105:            public void setTableName(String table) {
106:                _tableName = table;
107:            }
108:
109:            public boolean init(int clusterLength) throws Exception {
110:                if (_path == null)
111:                    throw new ConfigException(L.l("file-backing needs path."));
112:
113:                if (_tableName == null)
114:                    throw new ConfigException(L
115:                            .l("file-backing needs tableName."));
116:
117:                int length = clusterLength;
118:
119:                if (length <= 0)
120:                    length = 1;
121:
122:                _loadQuery = "SELECT access_time,data FROM " + _tableName
123:                        + " WHERE id=? AND is_valid=1";
124:                _insertQuery = ("INSERT into "
125:                        + _tableName
126:                        + " (id,is_valid,data,mod_time,access_time,expire_interval,server1,server2,server3) " + "VALUES(?,1,?,?,?,?,?,?,?)");
127:                _updateQuery = "UPDATE "
128:                        + _tableName
129:                        + " SET data=?, mod_time=?, access_time=?,is_valid=1 WHERE id=?";
130:                _accessQuery = "UPDATE " + _tableName
131:                        + " SET access_time=? WHERE id=?";
132:                _setExpiresQuery = "UPDATE " + _tableName
133:                        + " SET expire_interval=? WHERE id=?";
134:                _invalidateQuery = "UPDATE " + _tableName
135:                        + " SET is_valid=0 WHERE id=?";
136:
137:                // access window is 1/4 the expire interval
138:                _timeoutQuery = ("DELETE FROM " + _tableName + " WHERE access_time + 5 * expire_interval / 4 < ?");
139:
140:                _dumpQuery = ("SELECT id, is_valid, expire_interval, data"
141:                        + " FROM " + _tableName + " WHERE ? <= mod_time AND " + "   (?=server1 OR ?=server2 OR ?=server3)");
142:
143:                _countQuery = "SELECT count(*) FROM " + _tableName;
144:
145:                try {
146:                    _path.mkdirs();
147:                } catch (IOException e) {
148:                }
149:
150:                DataSourceImpl dataSource = new DataSourceImpl();
151:                dataSource.setPath(_path);
152:                dataSource.setRemoveOnError(true);
153:                dataSource.init();
154:
155:                _dataSource = dataSource;
156:
157:                initDatabase();
158:
159:                return true;
160:            }
161:
162:            /**
163:             * Returns the data source.
164:             */
165:            public DataSource getDataSource() {
166:                return _dataSource;
167:            }
168:
169:            /**
170:             * Create the database, initializing if necessary.
171:             */
172:            private void initDatabase() throws Exception {
173:                Connection conn = _dataSource.getConnection();
174:
175:                try {
176:                    Statement stmt = conn.createStatement();
177:
178:                    boolean hasDatabase = false;
179:
180:                    try {
181:                        String sql = "SELECT expire_interval,is_valid FROM "
182:                                + _tableName + " WHERE 1=0";
183:
184:                        ResultSet rs = stmt.executeQuery(sql);
185:                        rs.next();
186:                        rs.close();
187:
188:                        return;
189:                    } catch (Exception e) {
190:                        log.log(Level.FINEST, e.toString(), e);
191:                        log.finer(this  + " " + e.toString());
192:                    }
193:
194:                    try {
195:                        stmt.executeQuery("DROP TABLE " + _tableName);
196:                    } catch (Exception e) {
197:                        log.log(Level.FINEST, e.toString(), e);
198:                    }
199:
200:                    String sql = ("CREATE TABLE " + _tableName + " (\n"
201:                            + "  id VARBINARY(64) PRIMARY KEY,\n"
202:                            + "  is_valid BIT,\n" + "  data BLOB,\n"
203:                            + "  expire_interval INTEGER,\n"
204:                            + "  access_time INTEGER,\n"
205:                            + "  mod_time INTEGER,\n" + "  mod_count BIGINT,\n"
206:                            + "  server1 INTEGER,\n" + "  server2 INTEGER,\n" + "  server3 INTEGER)");
207:
208:                    log.fine(sql);
209:
210:                    stmt.executeUpdate(sql);
211:                } finally {
212:                    conn.close();
213:                }
214:            }
215:
216:            public long start() throws Exception {
217:                long delta = -Alarm.getCurrentTime();
218:
219:                Connection conn = null;
220:                try {
221:                    conn = _dataSource.getConnection();
222:
223:                    Statement stmt = conn.createStatement();
224:
225:                    String sql = "SELECT MAX(access_time) FROM " + _tableName;
226:
227:                    ResultSet rs = stmt.executeQuery(sql);
228:
229:                    if (rs.next())
230:                        delta = rs.getInt(1) * 60000L - Alarm.getCurrentTime();
231:                } finally {
232:                    if (conn != null)
233:                        conn.close();
234:                }
235:
236:                return delta;
237:            }
238:
239:            /**
240:             * Clears the old objects.
241:             */
242:            public void clearOldObjects(long maxIdleTime) throws SQLException {
243:                Connection conn = null;
244:
245:                try {
246:                    if (maxIdleTime > 0) {
247:                        conn = _dataSource.getConnection();
248:
249:                        PreparedStatement pstmt = conn
250:                                .prepareStatement(_timeoutQuery);
251:
252:                        long now = Alarm.getCurrentTime();
253:                        int nowMinute = (int) (now / 60000L);
254:
255:                        pstmt.setInt(1, nowMinute);
256:
257:                        int count = pstmt.executeUpdate();
258:
259:                        // System.out.println("OBSOLETE:" + count);
260:
261:                        if (count > 0)
262:                            log.fine(this  + " purged " + count
263:                                    + " old sessions");
264:
265:                        pstmt.close();
266:                    }
267:                } finally {
268:                    if (conn != null)
269:                        conn.close();
270:                }
271:            }
272:
273:            /**
274:             * Load the session from the jdbc store.
275:             *
276:             * @param session the session to fill.
277:             *
278:             * @return true if the load was valid.
279:             */
280:            public boolean loadSelf(ClusterObject clusterObj, Object obj)
281:                    throws Exception {
282:                String uniqueId = clusterObj.getUniqueId();
283:
284:                ClusterConnection conn = getConnection();
285:                try {
286:                    PreparedStatement stmt = conn.prepareLoad();
287:                    stmt.setString(1, uniqueId);
288:
289:                    ResultSet rs = stmt.executeQuery();
290:                    boolean validLoad = false;
291:
292:                    if (rs.next()) {
293:                        //System.out.println("LOAD: " + uniqueId);
294:                        long accessTime = rs.getInt(1) * 60000L;
295:
296:                        InputStream is = rs.getBinaryStream(2);
297:
298:                        if (log.isLoggable(Level.FINE))
299:                            log.fine(this  + " load " + uniqueId);
300:
301:                        validLoad = clusterObj.load(is, obj);
302:
303:                        if (validLoad)
304:                            clusterObj.setAccessTime(accessTime);
305:
306:                        is.close();
307:                    } else if (log.isLoggable(Level.FINE))
308:                        log.fine(this  + " load: no local object loaded for "
309:                                + uniqueId);
310:                    else {
311:                        // System.out.println("NO-LOAD: " + uniqueId);
312:                    }
313:
314:                    rs.close();
315:
316:                    return validLoad;
317:                } finally {
318:                    conn.close();
319:                }
320:            }
321:
322:            /**
323:             * Updates the object's access time.
324:             *
325:             * @param obj the object to store.
326:             */
327:            public void updateAccess(String uniqueId) throws Exception {
328:                ClusterConnection conn = getConnection();
329:
330:                try {
331:                    PreparedStatement stmt = conn.prepareAccess();
332:
333:                    long now = Alarm.getCurrentTime();
334:                    int nowMinutes = (int) (now / 60000L);
335:                    stmt.setInt(1, nowMinutes);
336:                    stmt.setString(2, uniqueId);
337:
338:                    int count = stmt.executeUpdate();
339:
340:                    if (count > 0) {
341:                        if (log.isLoggable(Level.FINE))
342:                            log.fine(this  + " access " + uniqueId);
343:                        return;
344:                    }
345:                } finally {
346:                    conn.close();
347:                }
348:            }
349:
350:            /**
351:             * Sets the object's expire_interval.
352:             *
353:             * @param obj the object to store.
354:             */
355:            public void setExpireInterval(String uniqueId, long expireInterval)
356:                    throws Exception {
357:                ClusterConnection conn = getConnection();
358:
359:                try {
360:                    PreparedStatement stmt = conn.prepareSetExpireInterval();
361:
362:                    int expireMinutes = (int) (expireInterval / 60000L);
363:                    stmt.setInt(1, expireMinutes);
364:                    stmt.setString(2, uniqueId);
365:
366:                    int count = stmt.executeUpdate();
367:
368:                    if (count > 0) {
369:                        if (log.isLoggable(Level.FINE))
370:                            log.fine(this  + " set expire interval: " + uniqueId
371:                                    + " " + expireInterval);
372:                        return;
373:                    }
374:                } finally {
375:                    conn.close();
376:                }
377:            }
378:
379:            /**
380:             * Removes the named object from the store.
381:             */
382:            public void remove(String uniqueId) throws Exception {
383:                ClusterConnection conn = getConnection();
384:
385:                try {
386:                    PreparedStatement pstmt = conn.prepareInvalidate();
387:                    pstmt.setString(1, uniqueId);
388:
389:                    int count = pstmt.executeUpdate();
390:
391:                    if (log.isLoggable(Level.FINE))
392:                        log.fine(this  + " remove " + uniqueId);
393:                } finally {
394:                    conn.close();
395:                }
396:            }
397:
398:            /**
399:             * Reads from the store.
400:             */
401:            public long read(String uniqueId, WriteStream os)
402:                    throws IOException {
403:                Connection conn = null;
404:                try {
405:                    conn = _dataSource.getConnection();
406:
407:                    PreparedStatement pstmt = conn.prepareStatement(_loadQuery);
408:                    pstmt.setString(1, uniqueId);
409:
410:                    ResultSet rs = pstmt.executeQuery();
411:                    if (rs.next()) {
412:                        long accessTime = rs.getInt(1) * 60000L;
413:
414:                        InputStream is = rs.getBinaryStream(2);
415:
416:                        os.writeStream(is);
417:
418:                        is.close();
419:
420:                        return accessTime;
421:                    }
422:                } catch (SQLException e) {
423:                    log.log(Level.FINE, e.toString(), e);
424:                } finally {
425:                    try {
426:                        if (conn != null)
427:                            conn.close();
428:                    } catch (SQLException e) {
429:                    }
430:                }
431:
432:                return -1;
433:            }
434:
435:            /**
436:             * Stores the cluster object on the local store.
437:             *
438:             * @param uniqueId the object's unique id.
439:             * @param id the input stream to the serialized object
440:             * @param length the length object the serialized object
441:             * @param expireInterval how long the object lives w/o access
442:             */
443:            public void storeSelf(String uniqueId, ReadStream is, int length,
444:                    long expireInterval, int primary, int secondary,
445:                    int tertiary) {
446:                ClusterConnection conn = null;
447:
448:                try {
449:                    conn = getConnection();
450:                    // Try to update first, and insert if fail.
451:                    // The binary stream can be reused because it won't actually be
452:                    // read on a failure
453:
454:                    if (storeSelfUpdate(conn, uniqueId, is, length)) {
455:                    } else if (storeSelfInsert(conn, uniqueId, is, length,
456:                            expireInterval, primary, secondary, tertiary)) {
457:                    } else {
458:                        // XXX: For now, avoid this case since the self-update query doesn't
459:                        // check for any update count, i.e. it can't tell which update is
460:                        // the most recent.  Also, the input stream would need to change
461:                        // to a tempStream to allow the re-write
462:
463:                        /*
464:                        if (storeSelfUpdate(conn, uniqueId, is, length)) {
465:                          // The second update is for the rare case where
466:                          // two threads try to update the database simultaneously
467:                        }
468:                        else {
469:                          log.fine(L.l("Can't store session {0}", uniqueId));
470:                        }
471:                         */
472:                    }
473:                } catch (SQLException e) {
474:                    log.log(Level.FINE, e.toString(), e);
475:                } finally {
476:                    if (conn != null)
477:                        conn.close();
478:                }
479:            }
480:
481:            /**
482:             * Stores the cluster object on the local store using an update query.
483:             *
484:             * @param conn the database connection
485:             * @param uniqueId the object's unique id.
486:             * @param id the input stream to the serialized object
487:             * @param length the length object the serialized object
488:             */
489:            private boolean storeSelfUpdate(ClusterConnection conn,
490:                    String uniqueId, ReadStream is, int length) {
491:                try {
492:                    PreparedStatement stmt = conn.prepareUpdate();
493:                    stmt.setBinaryStream(1, is, length);
494:
495:                    long now = Alarm.getCurrentTime();
496:                    int nowMinutes = (int) (now / 60000L);
497:                    stmt.setInt(2, nowMinutes);
498:                    stmt.setInt(3, nowMinutes);
499:                    stmt.setString(4, uniqueId);
500:
501:                    int count = stmt.executeUpdate();
502:
503:                    if (count > 0) {
504:                        if (log.isLoggable(Level.FINE))
505:                            log.fine(this  + " update " + uniqueId + " length:"
506:                                    + length);
507:
508:                        return true;
509:                    }
510:                } catch (SQLException e) {
511:                    log.log(Level.WARNING, e.toString(), e);
512:                }
513:
514:                return false;
515:            }
516:
517:            private boolean storeSelfInsert(ClusterConnection conn,
518:                    String uniqueId, ReadStream is, int length,
519:                    long expireInterval, int primary, int secondary,
520:                    int tertiary) {
521:                try {
522:                    PreparedStatement stmt = conn.prepareInsert();
523:
524:                    stmt.setString(1, uniqueId);
525:
526:                    stmt.setBinaryStream(2, is, length);
527:
528:                    int nowMinutes = (int) (Alarm.getCurrentTime() / 60000L);
529:
530:                    stmt.setInt(3, nowMinutes);
531:                    stmt.setInt(4, nowMinutes);
532:                    stmt.setInt(5, (int) (expireInterval / 60000L));
533:
534:                    stmt.setInt(6, primary);
535:                    stmt.setInt(7, secondary);
536:                    stmt.setInt(8, tertiary);
537:
538:                    stmt.executeUpdate();
539:
540:                    if (log.isLoggable(Level.FINE))
541:                        log.fine(this  + " insert " + uniqueId + " length:"
542:                                + length);
543:
544:                    return true;
545:                } catch (SQLException e) {
546:                    System.out.println(e);
547:
548:                    log.log(Level.FINE, e.toString(), e);
549:                }
550:
551:                return false;
552:            }
553:
554:            //
555:            // statistics
556:            //
557:
558:            public long getObjectCount() throws SQLException {
559:                ClusterConnection conn = getConnection();
560:
561:                try {
562:                    PreparedStatement stmt = conn.prepareCount();
563:
564:                    ResultSet rs = stmt.executeQuery();
565:
566:                    if (rs != null && rs.next()) {
567:                        long value = rs.getLong(1);
568:                        rs.close();
569:                        return value;
570:                    }
571:
572:                    return -1;
573:                } catch (SQLException e) {
574:                    log.log(Level.FINE, e.toString(), e);
575:                } finally {
576:                    conn.close();
577:                }
578:
579:                return -1;
580:            }
581:
582:            public void destroy() {
583:                _dataSource = null;
584:                _freeConn = null;
585:            }
586:
587:            private ClusterConnection getConnection() throws SQLException {
588:                ClusterConnection cConn = _freeConn.allocate();
589:
590:                if (cConn == null) {
591:                    Connection conn = _dataSource.getConnection();
592:                    cConn = new ClusterConnection(conn);
593:                }
594:
595:                return cConn;
596:            }
597:
598:            public String serverNameToTableName(String serverName) {
599:                if (serverName == null)
600:                    return "srun";
601:
602:                StringBuilder cb = new StringBuilder();
603:                cb.append("srun_");
604:
605:                for (int i = 0; i < serverName.length(); i++) {
606:                    char ch = serverName.charAt(i);
607:
608:                    if ('a' <= ch && ch <= 'z') {
609:                        cb.append(ch);
610:                    } else if ('A' <= ch && ch <= 'Z') {
611:                        cb.append(ch);
612:                    } else if ('0' <= ch && ch <= '9') {
613:                        cb.append(ch);
614:                    } else if (ch == '_') {
615:                        cb.append(ch);
616:                    } else
617:                        cb.append('_');
618:                }
619:
620:                return cb.toString();
621:            }
622:
623:            public String toString() {
624:                return getClass().getSimpleName() + "[" + _tableName + "]";
625:            }
626:
627:            class ClusterConnection {
628:                private Connection _conn;
629:
630:                private PreparedStatement _loadStatement;
631:                private PreparedStatement _updateStatement;
632:                private PreparedStatement _insertStatement;
633:                private PreparedStatement _accessStatement;
634:                private PreparedStatement _setExpiresStatement;
635:                private PreparedStatement _invalidateStatement;
636:                private PreparedStatement _timeoutStatement;
637:                private PreparedStatement _countStatement;
638:
639:                ClusterConnection(Connection conn) {
640:                    _conn = conn;
641:                }
642:
643:                PreparedStatement prepareLoad() throws SQLException {
644:                    if (_loadStatement == null)
645:                        _loadStatement = _conn.prepareStatement(_loadQuery);
646:
647:                    return _loadStatement;
648:                }
649:
650:                PreparedStatement prepareUpdate() throws SQLException {
651:                    if (_updateStatement == null)
652:                        _updateStatement = _conn.prepareStatement(_updateQuery);
653:
654:                    return _updateStatement;
655:                }
656:
657:                PreparedStatement prepareInsert() throws SQLException {
658:                    if (_insertStatement == null)
659:                        _insertStatement = _conn.prepareStatement(_insertQuery);
660:
661:                    return _insertStatement;
662:                }
663:
664:                PreparedStatement prepareAccess() throws SQLException {
665:                    if (_accessStatement == null)
666:                        _accessStatement = _conn.prepareStatement(_accessQuery);
667:
668:                    return _accessStatement;
669:                }
670:
671:                PreparedStatement prepareSetExpireInterval()
672:                        throws SQLException {
673:                    if (_setExpiresStatement == null)
674:                        _setExpiresStatement = _conn
675:                                .prepareStatement(_setExpiresQuery);
676:
677:                    return _setExpiresStatement;
678:                }
679:
680:                PreparedStatement prepareInvalidate() throws SQLException {
681:                    if (_invalidateStatement == null)
682:                        _invalidateStatement = _conn
683:                                .prepareStatement(_invalidateQuery);
684:
685:                    return _invalidateStatement;
686:                }
687:
688:                PreparedStatement prepareCount() throws SQLException {
689:                    if (_countStatement == null)
690:                        _countStatement = _conn.prepareStatement(_countQuery);
691:
692:                    return _countStatement;
693:                }
694:
695:                void close() {
696:                    if (_freeConn != null)
697:                        _freeConn.free(this);
698:                }
699:            }
700:        }
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