/*

 * Copyright 2005 Sun Microsystems, Inc.  All Rights Reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun in the LICENSE file that accompanied this code.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package javax.swing.event;

import javax.swing.RowSorter;

/**

 * <code>RowSorterEvent</code> provides notification of changes to

 * a <code>RowSorter</code>.  Two types of notification are possible:

 * <ul>

 * <li><code>Type.SORT_ORDER_CHANGED</code>: indicates the sort order has

 *     changed.  This is typically followed by a notification of:

 * <li><code>Type.SORTED</code>: indicates the contents of the model have

 *     been transformed in some way.  For example, the contents may have

 *     been sorted or filtered.

 * </ul>

 *

 * @see javax.swing.RowSorter

 * @since 1.6

 */

public class RowSorterEvent extends java.util.EventObject {

    private Type type;

    private int[] oldViewToModel;

    /**

     * Enumeration of the types of <code>RowSorterEvent</code>s.

     *

     * @since 1.6

     */

    public enum Type {

        /**

         * Indicates the sort order has changed.

         */

        SORT_ORDER_CHANGED,

        /**

         * Indicates the contents have been newly sorted or

         * transformed in some way.

         */

        SORTED

    }

    /**

     * Creates a <code>RowSorterEvent</code> of type

     * <code>SORT_ORDER_CHANGED</code>.

     *

     * @param source the source of the change

     * @throws IllegalArgumentException if <code>source</code> is

     *         <code>null</code>

     */

    public RowSorterEvent(RowSorter source) {

        this(source, Type.SORT_ORDER_CHANGED, null);

    }

    /**

     * Creates a <code>RowSorterEvent</code>.

     *

     * @param source the source of the change

     * @param type the type of event

     * @param previousRowIndexToModel the mapping from model indices to

     *        view indices prior to the sort, may be <code>null</code>

     * @throws IllegalArgumentException if source or <code>type</code> is

     *         <code>null</code>

     */

    public RowSorterEvent(RowSorter source, Type type,

                          int[] previousRowIndexToModel) {

        super(source);

        if (type == null) {

            throw new IllegalArgumentException("type must be non-null");

        }

        this.type = type;

        this.oldViewToModel = previousRowIndexToModel;

    }

    /**

     * Returns the source of the event as a <code>RowSorter</code>.

     *

     * @return the source of the event as a <code>RowSorter</code>

     */

    public RowSorter getSource() {

        return (RowSorter)super.getSource();

    }

    /**

     * Returns the type of event.

     *

     * @return the type of event

     */

    public Type getType() {

        return type;

    }

    /**

     * Returns the location of <code>index</code> in terms of the

     * model prior to the sort.  This method is only useful for events

     * of type <code>SORTED</code>.  This method will return -1 if the

     * index is not valid, or the locations prior to the sort have not

     * been provided.

     *

     * @param index the index in terms of the view

     * @return the index in terms of the model prior to the sort, or -1 if

     *         the location is not valid or the mapping was not provided.

     */

    public int convertPreviousRowIndexToModel(int index) {

        if (oldViewToModel != null && index >= 0 &&

                index < oldViewToModel.length) {

            return oldViewToModel[index];

        }

        return -1;

    }

    /**

     * Returns the number of rows before the sort.  This method is only

     * useful for events of type <code>SORTED</code> and if the

     * last locations have not been provided will return 0.

     *

     * @return the number of rows in terms of the view prior to the sort

     */

    public int getPreviousRowCount() {

        return (oldViewToModel == null) ? 0 : oldViewToModel.length;

    }

}