StatisticsCache.java

/////////////////////////////////////////////////////////////////////////////
//
// Project ProjectForge Community Edition
//         www.projectforge.org
//
// Copyright (C) 2001-2014 Kai Reinhard (k.reinhard@micromata.de)
//
// ProjectForge is dual-licensed.
//
// This community edition is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License as published
// by the Free Software Foundation; version 3 of the License.
//
// This community edition is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
// Public License for more details.
//
// You should have received a copy of the GNU General Public License along
// with this program; if not, see http://www.gnu.org/licenses/.
//
/////////////////////////////////////////////////////////////////////////////

package org.projectforge.database;

import java.util.HashMap;
import java.util.Map;

import javax.sql.DataSource;

import org.apache.log4j.Logger;
import org.projectforge.common.AbstractCache;
import org.projectforge.core.BaseDO;
import org.projectforge.registry.Registry;
import org.projectforge.registry.RegistryEntry;
import org.springframework.jdbc.core.JdbcTemplate;

/**
 * Stores the number of entities in the different tables (used by SearchPage).
 * @author Kai Reinhard (k.reinhard@micromata.de)
 */
public class StatisticsCache extends AbstractCache
{
  private static Logger log = Logger.getLogger(StatisticsCache.class);

  /** The key is the entity class and the value the number of entries in the table. */
  private Map<Class< ? extends BaseDO< ? >>, Integer> numberOfEntitiesMap;

  private DataSource dataSource;

  public void setDataSource(final DataSource dataSource)
  {
    this.dataSource = dataSource;
  }

  public Integer getNumberOfEntities(final Class< ? extends BaseDO< ? >> clazz)
  {
    checkRefresh();
    return numberOfEntitiesMap.get(clazz);
  }

  /**
   * This method will be called by CacheHelper and is synchronized via getData();
   */
  protected void refresh()
  {
    log.info("Initializing StatisticsCache ...");
    numberOfEntitiesMap = new HashMap<Class< ? extends BaseDO< ? >>, Integer>();
    final JdbcTemplate jdbc = new JdbcTemplate(dataSource);
    for (final RegistryEntry registryEntry : Registry.instance().getOrderedList()) {
      try {
        final int number = jdbc.queryForInt("SELECT COUNT(*) FROM " + HibernateUtils.getDBTableName(registryEntry.getDOClass()));
        numberOfEntitiesMap.put(registryEntry.getDOClass(), number);
      } catch (final Exception ex) {
        log.error(ex.getMessage(), ex);
        continue;
      }
    }
    log.info("Initializing of StatisticsCache done.");
  }
}