cachetodohandler.java

iiitAccessServer是一个用Java编写的基于规则的企业鉴别系统。它作为一个服务器工作

        
        String filter = "(& (" + ldapFormulaExpr + "=*" + expression + "*)(objectClass=" + ldapFormulaClass + "))";
        
        long t = System.currentTimeMillis();
  
        Vector v = ldapUtil.search(ldapFormulaBase, filter, new String[] {ldapCommonName});
        t = System.currentTimeMillis() - t;
        
        int iMax = v.size();
        for (int i = 0; i < iMax; i++)
        {
            Vector m = ((LdapGenericObject) v.get(i)).getAttribute(ldapCommonName);
            
            int jMax = m.size();
            
            for (int j = 0; j < jMax; j++)
            {
                String cn = (String) m.get(j);
                result.add(cn);
            }
        }

        return result;
    }
    
    private Vector collectReferences(String expression) throws NamingException, JdbcException, CacheManagerException
    {
        String s, expr;
        
        long t = System.currentTimeMillis();

        // Search for direct references
        Vector result = new Vector(searchReferences(expression));

        if (result.contains(expression))
            throw new CacheManagerException("Found circular reference inside expression <" + expression + ">");
            
        // Search for indirect references
        for (int i = 0; i < result.size(); i++)
        {
            expr = (String) result.get(i);
                        
            Set r = searchReferences(expr);

            Iterator iterator = r.iterator();
            while(iterator.hasNext())
            {
                s = (String) iterator.next();
                
                if (s.equalsIgnoreCase(expression))
                    throw new CacheManagerException("Found circular reference to expression <" + expression + "> in expression <" + expr + ">");
                
                if (!result.contains(s))
                    result.add(s);
            }
        }
        
        t = System.currentTimeMillis() - t;
        logger.info(result.size() + " references to <" + expression + "> found, " + t + " ms");
        
        return result;
    }
    
    private void touchReferences(String expression, Vector references) throws NamingException, JdbcException, CacheManagerException
    {
        int iMax = references.size();

        for (int i = 0; i < iMax; i++)
        {
            String cn = (String) references.get(i);
            logger.info("References to <" + expression + "> found in <" + cn + ">");
            ToDoList todo = new ToDoList(cn, System.currentTimeMillis(), false);
            todo.insertToDo(adminPool);
        }
    }
    
    private void updateCache(String expression, long touchTime) throws JdbcException, ParserException
    {
        try
        {
            if (ignoreCase)
                expression = expression.toLowerCase();
                
            long  time = System.currentTimeMillis();

            String md5 = Md5Cache.get(expression);

            if (md5 == null)
            {
                md5 = StringUtil.md5Sum(expression);
                Md5Cache.put(expression, md5);
            }

            Parser p = new Parser();
            p.setReturnEmptySets(true);
            
            Set s = p.evaluateExpression(expression);
        
            JdbcConnectionPool cachePool = manager.getCacheConnectionPool(md5);
            IndexTable  index   = IndexTable.selectIndex(cachePool, md5);
        
            if (s != null && s.size() > 0)
            {
                if (index == null || index.getCreationTime() <= touchTime)
                {
                    String name = nextTableName(cachePool);

                    CacheTable.createCacheTable(cachePool, name);

                    long t = System.currentTimeMillis();

                    CacheTable.insertCacheTable(cachePool, name, s, ignoreCase);

                    t = System.currentTimeMillis() - t;
                    logger.info(s.size() + " records written to table <" + name + ">, " + t + " ms");
            
                    if (index != null)
                    {
                        String oldTable = index.getTableName();
            
                        index.setTableName(name);
                        index.setCreationTime(time);
                
                        index.updateIndex(cachePool);
                
                        CacheTable.dropCacheTable(cachePool, oldTable);
                    }
                    else
                    {
                        index = new IndexTable(md5, name, time);
                        index.insertIndex(cachePool);
                    }
                }
                else
                {
                    logger.info("Cache for <" + expression + "> is uptodate");
                }            
            }
            else if (index != null)
            {
                String oldTable = index.getTableName();
            
                index.deleteIndex(cachePool);
                
                CacheTable.dropCacheTable(cachePool, oldTable);
            }
        }
        catch(NoSuchAlgorithmException nsae)
        {
            logger.fatal("Initialisation of MD5 digest failed.", nsae);
            System.exit(1);
        }
    }
        
    /** The main method of the CacheToDoHandler thread. */    
    public void run()
    {
        cachePoolCount = manager.getCachePoolCount();
        adminPool = manager.getAdminPool();
        
        initializeAdminDb();
        initializeCacheDb();
          
        fillToDoList();
        
        fileHandler.start();

        while(running)
        {
            try 
            {
                boolean loop = true;
                    
                do
                {
                    ToDoList todo = ToDoList.selectToDo(adminPool);
                            
                    if (todo != null)
                    {
                        String expression = todo.getExpression();
                        
                        logger.info("Found expr=<" + expression + ">");
                            
                        todo.setLocked(true);
                        todo.updateToDo(adminPool);

                        try
                        {
                            Vector references = collectReferences(expression);
                            updateCache(expression, todo.getTouchTime());
                            touchReferences(expression, references);
                        }
                        catch(CacheManagerException cme)
                        {
                            String msg = "Circular reference error in <" + expression + ">: " + cme.getMessage();
                            logger.fatal(msg);
                            manager.errorHandler().sendMail(msg);
                        }
                        catch(ParserException pe)
                        {
                            String msg = "Parser error in <" + expression + ">: " + pe.getMessage();
                            logger.fatal(msg);
                            manager.errorHandler().sendMail(msg);
                        }
                        
                        todo.deleteToDo(adminPool);
                    }
                    else
                    {
                        loop = false;
                    }
                }
                while (loop);

                for (int i = 0; i < cachePoolCount; i++)
                    CacheTable.dropLostTables(manager.getCacheConnectionPool(i));
                
                try
                {
                    if (running)
                        sleep(sleepTime);
                }
                catch(InterruptedException ie)
                {
                    // do nothing
                }
            }
            catch(Exception e)
            {
                logger.error("Cought error while trying to read <todotable>", e);

                try
                {
                    if (running)
                        sleep(sleepTime);
                }
                catch(InterruptedException ie)
                {
                    // do nothing
                }
            }
        }
        
        running = false;
    }

}

/**
 * $Log: CacheToDoHandler.java,v $
 * Revision 1.27  2003/04/14 20:41:09  joerg
 * Setting name for thread.
 *
 * Revision 1.26  2003/04/13 21:09:56  joerg
 * Package structure modified
 *
 * Revision 1.25  2003/04/13 20:28:01  joerg
 * Package structure modified
 *
 * Revision 1.24  2003/04/13 20:16:41  joerg
 * Package structure modified
 *
 * Revision 1.23  2003/01/29 20:32:06  joerg
 * MD5-Summen werden zuerst im Cache gesucht.
 *
 * Revision 1.22  2003/01/16 21:47:01  joerg
 * Kleine Bugfixes
 *
 * Revision 1.21  2003/01/04 17:15:43  joerg
 * Zus鋞zliche Config-Option IgnoreCase
 *
 * Revision 1.20  2003/01/01 21:04:17  joerg
 * Copyright-Statement aktualisiert
 *
 * Revision 1.19  2002/12/27 20:22:31  joerg
 * Initiales Einlesen der LDAP Daten komplett ueberarbeitet, bei
 * LDAP-Fehlern wird nicht mehr System.exit() aufgerufen, sondern
 * ein reconnect versucht.
 *
 * Revision 1.18  2002/12/24 21:04:33  joerg
 * Umbau der Paketstruktur
 * iiitLdapPlugin integriert
 * JavaDoc-Kommentare weiter vervollstaendigt.
 *
 * Revision 1.17  2002/12/23 11:25:53  joerg
 * shutdown()-Methode hinzugefuegt.
 *
 * Revision 1.16  2002/12/21 19:55:03  joerg
 * Nicht mehr benoetigte Methoden entfernt, interne Methoden auf
 * private oder protected geaendert.
 * JavaDoc Kommentare ergaenzt.
 *
 * Revision 1.15  2002/12/19 15:54:33  joerg
 * Paket umbenannt in iiitLdapPlugin
 *
 * Revision 1.14  2002/12/08 16:37:33  joerg
 * Aufraeumungsarbeiten nach dem grossen Umbau
 *
 * Revision 1.13  2002/12/08 16:09:46  joerg
 * Paket-Struktur ueberarbeitet
 *
 * Revision 1.12  2002/12/08 13:55:31  joerg
 * Der Zugriff auf das LdapPlugin erfolgt jetzt ueber den CacheManager
 * und nicht mehr ueber den AccessServer
 *
 * Revision 1.11  2002/11/27 16:43:04  joerg
 * Parameteruebergabe geaendert, um circulaere Recursion
 * zu erkennen
 *
 * Revision 1.10  2002/11/27 12:13:49  joerg
 * Beim Erkennen fehlerhafte Ausdruecke kann jetzt automatisch
 * eine Fehler-Mail verschickt werden.
 *
 * Revision 1.9  2002/11/26 21:56:06  joerg
 * Circulaere Referenzen werden jetzt erkannt
 * Fehlerbehandlung verbessert
 *
 * Revision 1.8  2002/11/26 10:56:40  joerg
 * Package exprparser durch parser erstzt.
 *
 * Revision 1.7  2002/11/21 21:49:45  joerg
 * Umstellung auf JdbcConnectionPool
 *
 * Revision 1.6  2002/11/20 20:41:29  joerg
 * Klassen fuer das HAndling der DB-Tabellen in Packages
 * de.iiit.AccessServer.db.* verschoben
 *
 * Revision 1.5  2002/11/20 20:28:07  joerg
 * Bezuege auf Spalte 'inverted' in 'IndexTable' entfernt
 *
 * Revision 1.4  2002/11/18 22:09:00  joerg
 * CacheManager ausgelagert als PlugIn
 *
 * Revision 1.3  2002/11/18 21:21:52  joerg
 * LDAP-Anbindung auf LdapPlugin umgestellt.
 *
 * Revision 1.2  2002/11/18 15:21:41  joerg
 * LDAP-Suche jetzt ueber die Klasse LdapClient realisiert.
 *
 * Revision 1.1  2002/11/18 10:17:49  joerg
 * Klassen des CacheManagers in eigenes Package verschoben
 *
 * Revision 1.2  2002/11/18 10:13:18  joerg
 * CacheManager ist jetzt vollstaendig implementiert
 *
 * Revision 1.1  2002/11/17 22:03:26  joerg
 * Neue Klassen fuer 2nd-level Cache
 *
 */