001    /*
002     *    GeoAPI - Java interfaces for OGC/ISO standards
003     *    http://www.geoapi.org
004     *
005     *    Copyright (C) 2006-2012 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.filter;
033    
034    import java.io.ObjectStreamException;
035    import java.io.Serializable;
036    
037    
038    /**
039     * Indicating "filter all", evaluates to {@code false}.
040     * This is a placeholder filter intended to be used in data structuring definition.
041     * <p>
042     * <ul>
043     *   <li>EXCLUDE or Filter ==> Filter</li>
044     *   <li>EXCLUDE and Filter ==> EXCLUDE</li>
045     *   <li>EXCLUDE ==> INCLUDE</li>
046     * </ul>
047     * <p>
048     * The above does imply that the AND opperator can short circuit on encountering ALL.
049     *
050     * @author Jody Garnett (Refractions Research, Inc.)
051     * @author Martin Desruisseaux (Geomatys)
052     */
053    public final class ExcludeFilter implements Filter, Serializable {
054        /**
055         * For cross-version compatibility.
056         */
057        private static final long serialVersionUID = -716705962006999508L;
058    
059        /**
060         * Not extensible.
061         */
062        ExcludeFilter() {
063        }
064    
065        /**
066         * Accepts a visitor.
067         */
068        public Object accept(FilterVisitor visitor, Object extraData) {
069            return visitor.visit(this, extraData);
070        }
071    
072        /**
073         * Returns {@code false}, content is excluded.
074         */
075        public boolean evaluate(Object object) {
076            return false;
077        }
078    
079        /**
080         * Returns a string representation of this filter.
081         */
082        @Override
083        public String toString() {
084            return "Filter.EXCLUDE";
085        }
086    
087        /**
088         * Returns the canonical instance on deserialization.
089         */
090        private Object readResolve() throws ObjectStreamException {
091            return Filter.EXCLUDE;
092        }
093    }