content: /* ========================================================================
   * JCommon : a free general purpose class library for the Java(tm) platform
   * ========================================================================
   *
   * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
   *
   * Project Info:  http://www.jfree.org/jcommon/index.html
   *
   * 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
   * USA.
   *
   * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
   * in the United States and other countries.]
   *
   * -----------------------
   * SortableTableModel.java
   * -----------------------
   * (C) Copyright 2000-2005, by Object Refinery Limited;
   *
   * Original Author:  David Gilbert (for Object Refinery Limited);
   * Contributor(s):   -;
   *
   * $Id: SortableTableModel.java,v 1.6 2008/09/10 09:26:11 mungady Exp $
   *
   * Changes (from 26-Oct-2001)
   * --------------------------
   * 26-Oct-2001 : Changed package to com.jrefinery.ui.* (DG);
   * 20-Nov-2001 : Made constructor protected (DG);
   * 14-Oct-2002 : Fixed errors reported by Checkstyle (DG);
   *
   */
  
  package org.jfree.ui;
  
  import javax.swing.table.AbstractTableModel;
  
  /**
   * The base class for a sortable table model.
   *
   * @author David Gilbert
   */
  public abstract class SortableTableModel extends AbstractTableModel {
  
      /** The column on which the data is sorted (-1 for no sorting). */
      private int sortingColumn;
  
      /** Indicates ascending (true) or descending (false) order. */
      private boolean ascending;
  
      /**
       * Constructs a sortable table model.
       */
      public SortableTableModel() {
          this.sortingColumn = -1;
          this.ascending = true;
      }
  
      /**
       * Returns the index of the sorting column, or -1 if the data is not sorted
       * on any column.
       *
       * @return the column used for sorting.
       */
      public int getSortingColumn() {
          return this.sortingColumn;
      }
  
      /**
       * Returns <code>true</code> if the data is sorted in ascending order, and
       * <code>false</code> otherwise.
       *
       * @return <code>true</code> if the data is sorted in ascending order, and
       *         <code>false</code> otherwise.
       */
      public boolean isAscending() {
          return this.ascending;
      }
  
      /**
       * Sets the flag that determines whether the sort order is ascending or
       * descending.
       *
       * @param flag  the flag.
       */
      public void setAscending(final boolean flag) {
          this.ascending = flag;
      }
  
      /**
       * Sorts the table.
       *
       * @param column  the column to sort on (zero-based index).
       * @param ascending  a flag to indicate ascending order or descending order.
       */
      public void sortByColumn(final int column, final boolean ascending) {
          if (isSortable(column)) {
              this.sortingColumn = column;
          }
      }
  
      /**
       * Returns a flag indicating whether or not a column is sortable.
       *
       * @param column  the column (zero-based index).
       *
       * @return boolean.
       */
      public boolean isSortable(final int column) {
          return false;
      }
  
  }
  