001    /**
002     * ========================================
003     * JFreeReport : a free Java report library
004     * ========================================
005     *
006     * Project Info:  http://reporting.pentaho.org/
007     *
008     * (C) Copyright 2000-2007, by Object Refinery Limited, Pentaho Corporation and Contributors.
009     *
010     * This library is free software; you can redistribute it and/or modify it under the terms
011     * of the GNU Lesser General Public License as published by the Free Software Foundation;
012     * either version 2.1 of the License, or (at your option) any later version.
013     *
014     * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
015     * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
016     * See the GNU Lesser General Public License for more details.
017     *
018     * You should have received a copy of the GNU Lesser General Public License along with this
019     * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
020     * Boston, MA 02111-1307, USA.
021     *
022     * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
023     * in the United States and other countries.]
024     *
025     * ------------
026     * $Id: EmptyReportDataFactory.java 2725 2007-04-01 18:49:29Z taqua $
027     * ------------
028     * (C) Copyright 2000-2005, by Object Refinery Limited.
029     * (C) Copyright 2005-2007, by Pentaho Corporation.
030     */
031    
032    package org.jfree.report;
033    
034    /**
035     * Creation-Date: 17.11.2006, 16:51:01
036     *
037     * @author Thomas Morgner
038     */
039    public class EmptyReportDataFactory implements ReportDataFactory
040    {
041      public EmptyReportDataFactory()
042      {
043      }
044    
045      public void open()
046      {
047    
048      }
049    
050      /**
051       * Queries a datasource. The string 'query' defines the name of the query. The
052       * Parameterset given here may contain more data than actually needed.
053       * <p/>
054       * The dataset may change between two calls, do not assume anything!
055       *
056       * @param query
057       * @param parameters
058       * @return
059       */
060      public ReportData queryData(final String query, final DataSet parameters)
061          throws ReportDataFactoryException
062      {
063        return new EmptyReportData();
064      }
065    
066      /**
067       * Closes the report data factory and all report data instances that have been
068       * returned by this instance.
069       */
070      public void close()
071      {
072    
073      }
074    
075    
076      /**
077       * Derives a freshly initialized report data factory, which is independend of
078       * the original data factory. Opening or Closing one data factory must not
079       * affect the other factories.
080       *
081       * @return
082       */
083      public ReportDataFactory derive()
084      {
085        return this;
086      }
087    }