/**************************************************************************
/* This class extends ItemCountFunction: it only counts items != null
/*
/* Copyright (c) 2004 by Bernhard Bablok (mail@bablokb.de)
/*
/* This program 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; either version 2 of the License or
/* (at your option) any later version.
/*
/* This program 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; see the file COPYING.  If not, write to
/* the Free Software Foundation Inc., 59 Temple Place - Suite 330,
/* Boston, MA  02111-1307 USA
/**************************************************************************/

import org.jfree.report.function.*;
import org.jfree.report.event.*;

/**
   This class extends ItemCountFunction: it only counts items != null

   @version $Revision: 1.1 $
   @author  $Author: bablokb $
*/

public class ItemNotNullCountFunction extends ItemCountFunction {

  public static final String FIELD_PROPERTY = "field";

  //////////////////////////////////////////////////////////////////////////////

  /**
     Returns the name of the field (possibly null) for this function.
     The item count is incremented for values != null of this field.
    
     @return the field name.
   */
  public String getField() {
    return getProperty(FIELD_PROPERTY);
  }

  //////////////////////////////////////////////////////////////////////////////

  /**
     Setss the name of the field for this function.
     The item count is incremented for values != null of this field.
    
     @param field The field name.
   */
  public void setField(String field) {
    setProperty(FIELD_PROPERTY,field);
  }

  //////////////////////////////////////////////////////////////////////////////

  /**
     Received notification of a move to the next row of data.
     Increments the item count (overridden to increment the count only if
     the field is not null).
    
     @param event Information about the event.
   */

  public void itemsAdvanced(final ReportEvent event) {
    if (getDataRow().get(getField()) != null)
      setCount(getCount() + 1);
  }
}