www.pudn.com > jfreereport-0.8.3f.zip > SelectCardFunction.java

/** 
 * ======================================== 
 * JFreeReport : a free Java report library 
 * ======================================== 
 * 
 * Project Info:  http://www.jfree.org/jfreereport/index.html 
 * Project Lead:  Thomas Morgner; 
 * 
 * (C) Copyright 2000-2003, by Simba Management Limited and Contributors. 
 * 
 * This library is free software; you can redistribute it and/or modify it under the terms 
 * of the GNU Lesser General Public License as published by the Free Software Foundation; 
 * either version 2.1 of the License, or (at your option) any later version. 
 * 
 * This library 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 Lesser General Public License for more details. 
 * 
 * You should have received a copy of the GNU Lesser General Public License along with this 
 * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, 
 * Boston, MA 02111-1307, USA. 
 * 
 * ----------------------- 
 * SelectCardFunction.java 
 * ----------------------- 
 * (C)opyright 2003, by Thomas Morgner and Contributors. 
 * 
 * Original Author:  Thomas Morgner; 
 * Contributor(s):   David Gilbert (for Simba Management Limited); 
 * 
 * $Id: SelectCardFunction.java,v 1.6.2.1 2003/08/24 14:18:07 taqua Exp $ 
 * 
 * Changes 
 * ------- 
 * 29.03.2003 : Initial version 
 */ 
package com.jrefinery.report.demo.cards; 
 
import java.io.Serializable; 
 
import com.jrefinery.report.Band; 
import com.jrefinery.report.Element; 
import com.jrefinery.report.event.ReportEvent; 
import com.jrefinery.report.function.AbstractFunction; 
import com.jrefinery.report.function.FunctionInitializeException; 
 
/** 
 * The SelectCardFunction defines the visiblity of the card bands depending 
 * on the current card type. 
 * 
 * Valid property names are: 
 * 
 
 * 
Account 
 * 
Admin 
 * 
User 
 * 
Prepaid 
 * 
Free 
 * 
Empty 
 * 
 
 * 
 * @author Thomas Morgner. 
 */ 
public class SelectCardFunction extends AbstractFunction implements Serializable 
{ 
  /** Literal text for the field property. */ 
  public static final String FIELD_PROPERTY = "field"; 
 
  /** Literal text for the baseCard property. */ 
  public static final String BASECARD_PROPERTY = "baseCard"; 
 
  /** 
   * Default constructor. 
   */ 
  public SelectCardFunction() 
  { 
  } 
 
  /** 
   * Hides all bands, which are invalid for the current card type. 
   * A band declares its validity by having the same element name as the 
   * card type name. 
   * 
   * @param band the band that should be evaluated 
   */ 
  private void selectBand(final Band band) 
  { 
    CardType type = (CardType) getDataRow().get(getProperty(FIELD_PROPERTY)); 
    if (type == null) 
    { 
      type = CardType.EMPTY; 
    } 
 
    final String bandName = getProperty(type.getTypeName(), ""); 
 
    // if the special type empty is active, then everything will be hidden ... 
    if (type == CardType.EMPTY) 
    { 
      band.setVisible(false); 
    } 
    else 
    { 
      band.setVisible(true); 
 
      final Element[] elements = band.getElementArray(); 
      for (int i = 0; i < elements.length; i++) 
      { 
        if (elements[i] instanceof Band) 
        { 
          final Element e = elements[i]; 
          e.setVisible(e.getName().equals(bandName)); 
        } 
      } 
    } 
  } 
 
  /** 
   * Receives notification that a row of data is being processed. 
   * 
   * @param event  the event. 
   */ 
  public void itemsAdvanced(final ReportEvent event) 
  { 
    final Element[] elements = event.getReport().getItemBand().getElementArray(); 
    final String rootName = getProperty(BASECARD_PROPERTY, ""); 
    // the itemband contains several cards, every card is contained in a single band. 
    for (int i = 0; i < elements.length; i++) 
    { 
      if (elements[i] instanceof Band && elements[i].getName().equals(rootName)) 
      { 
        selectBand((Band) elements[i]); 
      } 
    } 
  } 
 
  /** 
   * Checks that the function has been correctly initialized. 
   * 
 
   * The only check performed at present is to make sure the name is not null. 
   * 
   * @throws FunctionInitializeException in case the function is not initialized properly. 
   */ 
  public void initialize() throws FunctionInitializeException 
  { 
    super.initialize(); 
    if (getProperty(BASECARD_PROPERTY) == null) 
    { 
      throw new FunctionInitializeException("'baseCard' property is not defined"); 
    } 
    if (getProperty(FIELD_PROPERTY) == null) 
    { 
      throw new FunctionInitializeException("'field' property is not defined"); 
    } 
  } 
 
  /** 
   * Return the current expression value. 
   * 
 
   * The value depends (obviously) on the expression implementation. 
   * 
   * @return the value of the function. 
   */ 
  public Object getValue() 
  { 
    return null; 
  } 
}