Application: gvSIG desktop

/**

 * gvSIG. Desktop Geographic Information System.

 *

 * Copyright (C) 2007-2013 gvSIG Association.

 *

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

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 3

 * of the License, or (at your option) any later version.

 *

 * This program 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 for more details.

 *

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

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,

 * MA  02110-1301, USA.

 *

 * For any additional information, do not hesitate to contact us

 * at info AT gvsig.com, or visit our website www.gvsig.com.

 */

package org.gvsig.fmap.mapcontext.events.listeners;

import java.util.ArrayList;

import java.util.Iterator;

import org.gvsig.fmap.mapcontext.events.AtomicEvent;

import org.gvsig.fmap.mapcontext.events.ColorEvent;

import org.gvsig.fmap.mapcontext.events.ExtentEvent;

import org.gvsig.fmap.mapcontext.events.ProjectionEvent;

import org.gvsig.fmap.mapcontext.layers.CancelationException;

import org.gvsig.fmap.mapcontext.layers.LayerCollectionEvent;

import org.gvsig.fmap.mapcontext.layers.LayerCollectionListener;

import org.gvsig.fmap.mapcontext.layers.LayerEvent;

import org.gvsig.fmap.mapcontext.layers.LayerListener;

import org.gvsig.fmap.mapcontext.layers.LayerPositionEvent;

import org.gvsig.fmap.mapcontext.layers.SelectionEvent;

import org.gvsig.fmap.mapcontext.layers.SelectionListener;

import org.gvsig.fmap.mapcontext.rendering.legend.events.LegendChangedEvent;

import org.gvsig.fmap.mapcontext.rendering.legend.events.listeners.LegendListener;

/**

 * <p><code>EventBuffer</code> represents a buffer of events that allows store listeners of events produced in layers

 *  of a <code>MapContext</code> instance, and configure its dispatching mode.</p>

 * 

 * <p>The <i>dispatching mode</i>:

 * <ul>

 *  <li><code>true</code> : dispatches each new event received.</li>

 *  <li><code>false</code> : accumulates all new events received in a internal buffer, and only will dispatch them

 *   (according to the order they were received) when changes the mode.</li>

 * </ul>

 * </p>

 *

 * @see LegendListener

 * @see LayerCollectionListener

 * @see SelectionListener

 * @see ViewPortListener

 * @see LegendListener

 *

 * @author Fernando Gonz?lez Cort?s

 */

public class EventBuffer implements LegendListener, LayerCollectionListener,

SelectionListener, ViewPortListener, LayerListener {

        /**

         * List with all events received and don't dispatched.

         * 

         * @see #endAtomicEvent()

         * @see #legendChanged(LegendChangedEvent)

         * @see #layerAdded(LayerCollectionEvent)

         * @see #layerMoved(LayerPositionEvent)

         * @see #layerRemoved(LayerCollectionEvent)

         * @see #layerAdding(LayerCollectionEvent)

         * @see #layerMoving(LayerPositionEvent)

         * @see #layerRemoving(LayerCollectionEvent)

         * @see #visibilityChanged(LayerCollectionEvent)

         * @see #visibilityChanged(LayerEvent)

         * @see #selectionChanged(SelectionEvent)

         * @see #extentChanged(ExtentEvent)

         * @see #activationChanged(LayerEvent)

         * @see #nameChanged(LayerEvent)

         * @see #backColorChanged(ColorEvent)

         * @see #editionChanged(LayerEvent)

         * @see #projectionChanged(ProjectionEvent)

         * @see #fireAtomicEventListener

         */

        private ArrayList events = new ArrayList();

        /**

         * List with all listeners registered.

         * 

         * @see #addAtomicEventListener(AtomicEventListener)

         * @see #removeAtomicEventListener(AtomicEventListener)

         */ 

        private ArrayList listeners = new ArrayList();

        /**

         * Allows enable or disable the <i>dispatching mode</i>.

         * 

         * @see #beginAtomicEvent()

         * @see #endAtomicEvent()

         */

        private boolean dispatching = true;

        /**

         * <p>Enables buffer in <i>accumulation event</i> mode.<p>

         * 

         * <p>All new events received, will be accumulated and won't notified to their respective listeners,

         *  until this buffer would received a call to {@link #endAtomicEvent() endAtomicEvent}.</p>

         * 

         * @see #endAtomicEvent()

         */

        public void beginAtomicEvent() {

                dispatching = false;

        }

        /**

         * <p>Disables buffer in <i>accumulation event</i> mode.</p>

         * 

         * <p>All events accumulated will be notify to their respective

         *  listeners, in the same order as they arrived.</p>

         *  

         * @see #beginAtomicEvent()

         */

        public void endAtomicEvent() {

                fireAtomicEventListener();

                events.clear();

                dispatching = true;

        }

        /*

         * @see com.iver.cit.gvsig.fmap.layers.LegendListener#legendChanged(com.iver.cit.gvsig.fmap.rendering.LegendChangedEvent)

         */

        public void legendChanged(LegendChangedEvent e) {

                events.add(e);

                if (dispatching) {

                        fireAtomicEventListener();

                }

        }

        /*

         * @see com.iver.cit.gvsig.fmap.layers.LayerCollectionListener#layerAdded(com.iver.cit.gvsig.fmap.layers.LayerCollectionEvent)

         */

        public void layerAdded(LayerCollectionEvent e) {

                events.add(e);

                if (dispatching) {

                        fireAtomicEventListener();

                }

        }

        /*

         * @see com.iver.cit.gvsig.fmap.layers.LayerCollectionListener#layerMoved(com.iver.cit.gvsig.fmap.layers.LayerPositionEvent)

         */

        public void layerMoved(LayerPositionEvent e) {

                events.add(e);

                if (dispatching) {

                        fireAtomicEventListener();

                }

        }

        /*

         * @see com.iver.cit.gvsig.fmap.layers.LayerCollectionListener#layerRemoved(com.iver.cit.gvsig.fmap.layers.LayerCollectionEvent)

         */

        public void layerRemoved(LayerCollectionEvent e) {

                events.add(e);

                if (dispatching) {

                        fireAtomicEventListener();

                }

        }

        /*

         * @see com.iver.cit.gvsig.fmap.layers.LayerCollectionListener#layerAdding(com.iver.cit.gvsig.fmap.layers.LayerCollectionEvent)

         */

        public void layerAdding(LayerCollectionEvent e) throws CancelationException {

                events.add(e);

                if (dispatching) {

                        fireAtomicEventListener();

                }

        }

        /*

         * @see com.iver.cit.gvsig.fmap.layers.LayerCollectionListener#layerMoving(com.iver.cit.gvsig.fmap.layers.LayerPositionEvent)

         */

        public void layerMoving(LayerPositionEvent e) throws CancelationException {

                events.add(e);

                if (dispatching) {

                        fireAtomicEventListener();

                }

        }

        /*

         * @see com.iver.cit.gvsig.fmap.layers.LayerCollectionListener#layerRemoving(com.iver.cit.gvsig.fmap.layers.LayerCollectionEvent)

         */

        public void layerRemoving(LayerCollectionEvent e)

        throws CancelationException {

                events.add(e);

                if (dispatching) {

                        fireAtomicEventListener();

                }

        }

        /*

         * @see com.iver.cit.gvsig.fmap.layers.LayerCollectionListener#visibilityChanged(com.iver.cit.gvsig.fmap.layers.LayerCollectionEvent)

         */

        public void visibilityChanged(LayerCollectionEvent e)

        throws CancelationException {

                events.add(e);

                if (dispatching) {

                        fireAtomicEventListener();

                }

        }

        /*

         * @see com.iver.cit.gvsig.fmap.layers.SelectionListener#selectionChanged(com.iver.cit.gvsig.fmap.layers.SelectionEvent)

         */

        public void selectionChanged(SelectionEvent e) {

                events.add(e);

                if (dispatching) {

                        fireAtomicEventListener();

                }

        }

        /*

         * @see com.iver.cit.gvsig.fmap.ViewPortListener#extentChanged(com.iver.cit.gvsig.fmap.ExtentEvent)

         */

        public void extentChanged(ExtentEvent e) {

                events.add(e);

                if (dispatching) {

                        fireAtomicEventListener();

                }

        }

        /**

         * Appends, if wasn't, the specified listener to the end of the internal list of atomic event listeners.

         *

         * @param listener an object that implements the atomic event listener

         *

         * @return <code>true</code> if has added the listener successfully; otherwise <code>false</code>

         * 

         * @see #removeAtomicEventListener(AtomicEventListener)

         * @see #fireAtomicEventListener()

         */

        public boolean addAtomicEventListener(AtomicEventListener listener) {

                boolean bFound = false;

                for (int i=0; i < listeners.size(); i++)

                        if (listeners.get(i) == listener)

                                bFound = true;

                if (!bFound)

                        listeners.add(listener);

                return true; 

        }

        /**

         * <p>Removes a single instance of the {@link AtomicEventListener AtomicEventListener} from the

     * internal list, if it is present (optional operation). Returns <tt>true</tt>

     * if the list contained the specified element (or equivalently, if the list changed as a

     * result of the call).<p>

     *

     * @param o element to be removed from this list, if present

     * @return <tt>true</tt> if the list contained the specified element

     * 

     * @see #addAtomicEventListener(AtomicEventListener)

     * @see #fireAtomicEventListener()

         */

        public boolean removeAtomicEventListener(AtomicEventListener listener) {

                return listeners.remove(listener);

        }

        /**

         * Executes the {@linkplain AtomicEventListener#atomicEvent(AtomicEvent)} method of all listeners registered.

         * 

         * @see #addAtomicEventListener(AtomicEventListener)

         * @see #removeAtomicEventListener(AtomicEventListener)

         */

        private void fireAtomicEventListener() {

                if (events.size() == 0)

                        return; // No hay eventos que lanzar.

                for (Iterator i = listeners.iterator(); i.hasNext();) {

                        AtomicEventListener listener = (AtomicEventListener) i.next();

                        AtomicEvent e = new AtomicEvent(events);

                        listener.atomicEvent(e);

                }

                events.clear();

        }

        /*

         * @see com.iver.cit.gvsig.fmap.layers.LayerListener#visibilityChanged(com.iver.cit.gvsig.fmap.layers.LayerEvent)

         */

        public void visibilityChanged(LayerEvent e) {

                events.add(e);

                if (dispatching) {

                        fireAtomicEventListener();

                }

        }

        /*

         * @see com.iver.cit.gvsig.fmap.layers.LayerListener#activationChanged(com.iver.cit.gvsig.fmap.layers.LayerEvent)

         */

        public void activationChanged(LayerEvent e) {

                events.add(e);

                if (dispatching) {

                        fireAtomicEventListener();

                }

        }

        /*

         * @see com.iver.cit.gvsig.fmap.layers.LayerListener#nameChanged(com.iver.cit.gvsig.fmap.layers.LayerEvent)

         */

        public void nameChanged(LayerEvent e) {

                events.add(e);

                if (dispatching) {

                        fireAtomicEventListener();

                }

        }

        /*

         * @see com.iver.cit.gvsig.fmap.ViewPortListener#backColorChanged(com.iver.cit.gvsig.fmap.ColorEvent)

         */

        public void backColorChanged(ColorEvent e) {

                events.add(e);

                if (dispatching) {

                        fireAtomicEventListener();

                }

        }

        /*

         * @see com.iver.cit.gvsig.fmap.layers.LayerListener#editionChanged(com.iver.cit.gvsig.fmap.layers.LayerEvent)

         */

        public void editionChanged(LayerEvent e) {

                events.add(e);

                if (dispatching) {

                        fireAtomicEventListener();

                }

        }

        /*

         * @see com.iver.cit.gvsig.fmap.ViewPortListener#projectionChanged(com.iver.cit.gvsig.fmap.ProjectionEvent)

         */

        public void projectionChanged(ProjectionEvent e) {

                events.add(e);

                if (dispatching) {

                        fireAtomicEventListener();

                }

        }

        public void drawValueChanged(LayerEvent e) {

                events.add(e);

                if (dispatching) {

                        fireAtomicEventListener();

                }

        }

}