reportdefinitionselectionmodel.java

报表设计软件,很好的

/**
 * ========================================
 * JFreeReport : a free Java report library
 * ========================================
 *
 * Project Info:  http://www.jfree.org/jfreereport/index.html
 * Project Lead:  Thomas Morgner ([e-mail]);
 *
 * (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.
 *
 * ------------------------------
 * ReportDefinitionModel.java
 * ------------------------------
 * (C)opyright 2003, by Thomas Morgner and Contributors.
 *
 * Original Author:  Thomas Morgner;
 * Contributor(s):   David Gilbert (for Simba Management Limited);
 *
 * $Id: ReportDefinitionSelectionModel.java,v 1.2 2004/04/20 18:54:57 taqua Exp $
 *
 * Changes
 * -------------------------
 * 28.09.2003 : Initial version
 *
 */

package org.jfree.designer.visualeditor.bandeditor;

import java.util.ArrayList;

import org.jfree.report.Element;

public final class ReportDefinitionSelectionModel
{
  private final ArrayList selectionListeners;
  private final ArrayList selectedElements;
  private Element[] selectedElementsCached;

  public ReportDefinitionSelectionModel ()
  {
    selectedElements = new ArrayList();
    selectionListeners = new ArrayList();
  }

  public final boolean isSelected (final Element e)
  {
    return selectedElements.contains(e);
  }

  public final void addSelection (final Element e)
  {
    if (!isSelected(e))
    {
      selectedElements.add(e);
      selectedElementsCached = null;
      fireReportSelectionEvent
              (ReportSelectionEvent.SELECTION_ADDED, new Element[]{e});
    }
  }

  public final void removeSelection (final Element e)
  {
    if (isSelected(e))
    {
      selectedElements.remove(e);
      selectedElementsCached = null;
      fireReportSelectionEvent
              (ReportSelectionEvent.SELECTION_REMOVED, new Element[]{e});
    }
  }

  public final void clearSelection ()
  {
    final Element[] elements = (Element[])
            selectedElements.toArray(new Element[selectedElements.size()]);
    selectedElements.clear();
    selectedElementsCached = null;
    fireReportSelectionEvent
            (ReportSelectionEvent.SELECTION_REMOVED, elements);
  }

  public final Element[] getSelectedElements ()
  {
    if (selectedElementsCached == null)
    {
      selectedElementsCached = (Element[]) selectedElements.toArray
              (new Element[selectedElements.size()]);
    }
    return selectedElementsCached;
  }

  public final int getSelectionCount ()
  {
    return selectedElements.size();
  }

  protected final void fireReportSelectionEvent (final int type, final Element[] element)
  {
    final ReportSelectionEvent event =
            new ReportSelectionEvent(this, type, element);
    for (int i = 0; i < selectionListeners.size(); i++)
    {
      final ReportSelectionListener listener =
              (ReportSelectionListener) selectionListeners.get(i);
      listener.selectionChanged(event);
    }
  }

  public final void addReportSelectionListener (final ReportSelectionListener listener)
  {
    if (listener == null)
    {
      throw new NullPointerException();
    }
    selectionListeners.add(listener);
  }

  public final void removeReportSelectionListener (final ReportSelectionListener listener)
  {
    if (listener == null)
    {
      throw new NullPointerException();
    }
    selectionListeners.remove(listener);
  }

  public final Element getSelectedElement (final int selectionCount)
  {
    return (Element) selectedElements.get(selectionCount);
  }

}