001    /*
002     *    GeoAPI - Java interfaces for OGC/ISO standards
003     *    http://www.geoapi.org
004     *
005     *    Copyright (C) 2004-2012 Open Geospatial Consortium, Inc.
006     *    All Rights Reserved. http://www.opengeospatial.org/ogc/legal
007     *
008     *    Permission to use, copy, and modify this software and its documentation, with
009     *    or without modification, for any purpose and without fee or royalty is hereby
010     *    granted, provided that you include the following on ALL copies of the software
011     *    and documentation or portions thereof, including modifications, that you make:
012     *
013     *    1. The full text of this NOTICE in a location viewable to users of the
014     *       redistributed or derivative work.
015     *    2. Notice of any changes or modifications to the OGC files, including the
016     *       date changes were made.
017     *
018     *    THIS SOFTWARE AND DOCUMENTATION IS PROVIDED "AS IS," AND COPYRIGHT HOLDERS MAKE
019     *    NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
020     *    TO, WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE OR THAT
021     *    THE USE OF THE SOFTWARE OR DOCUMENTATION WILL NOT INFRINGE ANY THIRD PARTY
022     *    PATENTS, COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS.
023     *
024     *    COPYRIGHT HOLDERS WILL NOT BE LIABLE FOR ANY DIRECT, INDIRECT, SPECIAL OR
025     *    CONSEQUENTIAL DAMAGES ARISING OUT OF ANY USE OF THE SOFTWARE OR DOCUMENTATION.
026     *
027     *    The name and trademarks of copyright holders may NOT be used in advertising or
028     *    publicity pertaining to the software without specific, written prior permission.
029     *    Title to copyright in this software and any associated documentation will at all
030     *    times remain with copyright holders.
031     */
032    package org.opengis.display.canvas;
033    
034    import java.util.EventObject;
035    import org.opengis.referencing.operation.MathTransform;
036    
037    
038    /**
039     * Event sent by a {@linkplain Canvas canvas} to it registered listeners
040     * when its state changed.
041     *
042     * @author Open Geospatial Consortium
043     * @author Johann Sorel (Geomatys)
044     * @since  GeoAPI 2.2
045     */
046    public abstract class CanvasEvent extends EventObject {
047        /**
048         * Creates a new event having the given canvas as a source.
049         *
050         * @param  source The canvas on which the event initially occurred.
051         * @throws IllegalArgumentException If the given source is null.
052         */
053        public CanvasEvent(Canvas source) {
054            super(source);
055        }
056    
057        /**
058         * Returns the canvas on which the event occured.
059         *
060         * @return The source canvas.
061         */
062        @Override
063        public Canvas getSource() {
064            return (Canvas) super.getSource();
065        }
066    
067        /**
068         * Returns the canvas state prior the change.
069         *
070         * @return The old canvas state.
071         */
072        public abstract CanvasState getOldState();
073    
074        /**
075         * Returns the canvas state after the change.
076         *
077         * @return The new canvas state.
078         */
079        public abstract CanvasState getNewState();
080    
081        /**
082         * Returns the change from the {@linkplain #getOldState old state}
083         * to the {@linkplain #getNewState new state} in units of
084         * {@linkplain CanvasState#getObjectiveCRS objective CRS}.
085         * This change is typically (but is not restricted to) an affine transform.
086         * <p>
087         * <b>Example:</b> if the objective CRS uses a map projection with axis in metres,
088         * and if the user pan the map, then the change is an affine transform containing
089         * translation terms in metres.
090         *
091         * @return The change from the {@linkplain #getOldState old state} to the
092         *         {@linkplain #getNewState new state}, typically as an affine transform.
093         */
094        public abstract MathTransform getChange();
095    
096        /**
097         * Calculates to the given canvas state.
098         *
099         * @deprecated This method does not said is the change is computed from the old or the
100         *             new state. If we need this functionality, then the method should move to
101         *             {@link CanvasState}.
102         */
103        @Deprecated
104        public abstract MathTransform getChange(CanvasState other);
105        
106        public abstract RenderingState getOldRenderingstate();
107        
108        public abstract RenderingState getNewRenderingstate();
109        
110    }