001    //$HeadURL: svn+ssh://jwilden@svn.wald.intevation.org/deegree/base/branches/2.5_testing/src/org/deegree/graphics/AbstractLayer.java $
002    /*----------------------------------------------------------------------------
003     This file is part of deegree, http://deegree.org/
004     Copyright (C) 2001-2009 by:
005     Department of Geography, University of Bonn
006     and
007     lat/lon GmbH
008    
009     This library is free software; you can redistribute it and/or modify it under
010     the terms of the GNU Lesser General Public License as published by the Free
011     Software Foundation; either version 2.1 of the License, or (at your option)
012     any later version.
013     This library is distributed in the hope that it will be useful, but WITHOUT
014     ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
015     FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
016     details.
017     You should have received a copy of the GNU Lesser General Public License
018     along with this library; if not, write to the Free Software Foundation, Inc.,
019     59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
020    
021     Contact information:
022    
023     lat/lon GmbH
024     Aennchenstr. 19, 53177 Bonn
025     Germany
026     http://lat-lon.de/
027    
028     Department of Geography, University of Bonn
029     Prof. Dr. Klaus Greve
030     Postfach 1147, 53001 Bonn
031     Germany
032     http://www.geographie.uni-bonn.de/deegree/
033    
034     e-mail: info@deegree.org
035     ----------------------------------------------------------------------------*/
036    package org.deegree.graphics;
037    
038    import java.util.ArrayList;
039    import java.util.Collections;
040    import java.util.List;
041    
042    import org.deegree.model.crs.CRSFactory;
043    import org.deegree.model.crs.CoordinateSystem;
044    import org.deegree.model.spatialschema.Envelope;
045    import org.deegree.model.spatialschema.GeometryFactory;
046    
047    /**
048     * A Layer is a collection of <tt>Feature</tt>s or rasters building a thematic 'unit' waterways or country borders for
049     * example. <tt>Feature</tt>s or raster can be added or removed from the layer. A <tt>Feature</tt> or raster can e
050     * changed by a modul of the application using the layer because only references to <tt>Feature</tt>s or rasters are
051     * stored within a layer.
052     * 
053     * 
054     * @author <a href="mailto:poth@lat-lon.de">Andreas Poth</a>
055     * @version $Revision: 19800 $ $Date: 2009-09-26 12:33:09 +0200 (Sa, 26 Sep 2009) $
056     */
057    
058    abstract class AbstractLayer implements Layer {
059    
060        /**
061         * Of the layer
062         */
063        protected CoordinateSystem cs = null;
064    
065        /**
066         * bbox of the layer
067         */
068        protected Envelope boundingbox = null;
069    
070        /**
071         * List of controllers.
072         */
073        protected List<EventController> eventController = Collections.synchronizedList( new ArrayList<EventController>() );
074    
075        private String name = null;
076    
077        /**
078         * creates a layer with EPSG:4326 as default coordinate system
079         * 
080         * @param name
081         * @throws Exception
082         */
083        AbstractLayer( String name ) throws Exception {
084            this.name = name;
085            cs = CRSFactory.create( "EPSG:4326" );
086    
087        }
088    
089        /**
090         * Creates a new AbstractLayer object.
091         * 
092         * @param name
093         * @param crs
094         * 
095         * @throws Exception
096         */
097        AbstractLayer( String name, CoordinateSystem crs ) throws Exception {
098            this.name = name;
099    
100            cs = crs;
101    
102            boundingbox = GeometryFactory.createEnvelope( 9E99, 9E99, -9E99, -9E99, null );
103        }
104    
105        /**
106         * returns the name of the layer
107         * 
108         * @return the name of the layer
109         */
110        public String getName() {
111            return name;
112        }
113    
114        /**
115         * returns the BoundingBox (Envelope) of Layer. This is the BoundingBox of the layers data. The BoundingBox of the
116         * View maybe larger or smaller
117         * 
118         * @return the BoundingBox (Envelope) of Layer
119         */
120        public Envelope getBoundingBox() {
121            return boundingbox;
122        }
123    
124        /**
125         * returns the coordinate reference system of the MapView
126         * 
127         * @return the coordinate reference system of the MapView
128         */
129        public CoordinateSystem getCoordinatesSystem() {
130            return cs;
131        }
132    
133        /**
134         * adds an eventcontroller to the MapView that's reponsible for handling events that targets the map. E.g.: zooming,
135         * panning, selecting a feature etc.
136         * 
137         * @param obj
138         */
139        public void addEventController( LayerEventController obj ) {
140            eventController.add( obj );
141            obj.addLayer( this );
142        }
143    
144        /**
145         * @see org.deegree.graphics.AbstractLayer#addEventController(LayerEventController)
146         * @param obj
147         */
148        public void removeEventController( LayerEventController obj ) {
149            eventController.remove( obj );
150            obj.removeLayer( this );
151        }
152    
153        /**
154         * As default the method returns <code>true</code>, but it may be overwritten by extending classes
155         * 
156         * @return <code>true</code> if a layer is valid and should be rendered
157         */
158        public boolean isValid() {
159            return true;
160        }
161    }