Application: gvSIG desktop

package com.iver.cit.gvsig.fmap.layers.layerOperations;

import java.awt.Graphics2D;

import java.awt.image.BufferedImage;

import java.util.ArrayList;

import java.util.Collection;

import java.util.Iterator;

import com.iver.cit.gvsig.fmap.DriverException;

import com.iver.cit.gvsig.fmap.MapContext;

import com.iver.cit.gvsig.fmap.ViewPort;

import com.iver.cit.gvsig.fmap.layers.FLayer;

import com.iver.cit.gvsig.fmap.layers.LayerDrawEvent;

import com.iver.utiles.swing.threads.Cancellable;

/**

 * Abstract class for the classes that make able 

 * a single draw for a layers group

 *  

 * @see  com.iver.cit.gvsig.fmap.layers.FLayer#newComposedLayer()

 */

public abstract class ComposedLayer {

        ArrayList pendingLayersEvents= new ArrayList(); 

        MapContext mapContext = null; 

        public ComposedLayer(){

        }

        public void setMapContext(MapContext mapContext) {

                this.mapContext = mapContext;

        }

        /**

         * Checks if the layer can be added to this group

         * 

         * @param layer

         * @return layer can be added or not

         */

        public abstract boolean canAdd(FLayer layer);

        /**

         * Adds the layer to the draw group. 

         * You have to implements the doAdd(FLayer) method.

         * 

         * 

         * @see com.iver.cit.gvsig.fmap.layers.layerOperations.ComposedLayer#canAdd(FLayer)

         * 

         * @param layer

         * @throws Exception 

         */

        public final void add(FLayer layer) throws Exception {

                if (this.mapContext == null){

                        this.mapContext =layer.getMapContext();

                }

        doAdd(layer);

            pendingLayersEvents.add(layer);                

        }

        /**

         * Draws all the group in one pass

         * You have to implements the doDraw method. 

         *

         * @see  com.iver.cit.gvsig.fmap.layers.FLayer#draw(BufferedImage, Graphics2D, ViewPort, Cancellable, double)

         */

    public final void draw(BufferedImage image, Graphics2D g, ViewPort viewPort,

                        Cancellable cancel,double scale) throws DriverException {

            doDraw(image, g, viewPort, cancel, scale);

            fireLayerDrawingEvents(g,viewPort);

                pendingLayersEvents.clear();            

    }

        /**

         * Fires the event LayerDrawEvent.LAYER_AFTER_DRAW for every

         * layers of the group.

         * 

         *  

         *  @see com.iver.cit.gvsig.fmap.layers.LayerDrawEvent

         * 

         */

        private void fireLayerDrawingEvents(Graphics2D g, ViewPort viewPort) {

                Iterator iter = pendingLayersEvents.iterator();

                LayerDrawEvent afterEvent;

                FLayer layer = null ;

                while (iter.hasNext()) {

                        layer =(FLayer)iter.next();

                        afterEvent = new LayerDrawEvent(layer, g, viewPort, LayerDrawEvent.LAYER_AFTER_DRAW);

                        System.out.println("+++ evento " + afterEvent.getLayer().getName());

                        mapContext.fireLayerDrawingEvent(afterEvent);

                }

        }

        /**

         * Adds the layer to the draw group.

         * Specific implementation. 

         * 

         * @see com.iver.cit.gvsig.fmap.layers.layerOperations.ComposedLayer#add(FLayer)

         * 

         * @see com.iver.cit.gvsig.fmap.layers.layerOperations.ComposedLayer#canAdd(FLayer)

         * 

         * @param layer

         * @throws Exception 

         */

        protected abstract void doAdd(FLayer layer) throws Exception ;

        /**

         * Draws all the group in one pass.

         * Specific implementation. 

         *

         * @see  com.iver.cit.gvsig.fmap.layers.layerOperations.ComposedLayer#draw(BufferedImage, Graphics2D, ViewPort, Cancellable, double)

         *

         * @see  com.iver.cit.gvsig.fmap.layers.FLayer#draw(BufferedImage, Graphics2D, ViewPort, Cancellable, double)

         */        

        protected abstract void doDraw(BufferedImage image, Graphics2D g, ViewPort viewPort,

                        Cancellable cancel,double scale) throws DriverException ;

}