| gvSIG desktop 1

/* gvSIG. Sistema de Informaci?n Geogr?fica de la Generalitat Valenciana

 *

 * Copyright (C) 2006 IVER T.I. and Generalitat Valenciana.

 *

 * 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 2

 * 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307,USA.

 */

package org.gvsig.raster.buffer.cache;

import java.io.FileNotFoundException;

import java.io.IOException;

import org.gvsig.raster.dataset.NotSupportedExtensionException;

import org.gvsig.raster.dataset.RasterDataset;

import org.gvsig.raster.dataset.RasterDriverException;

import org.gvsig.raster.shared.Extent;

/**

 * Esta clase representa una p?gina de disco. Una p?gina de disco tendr? un n?mero de

 * p?gina asociado y un servidor de datos de disco por cada banda. 

 * 

 * @author Nacho Brodin (nachobrodin@gmail.com)

 */

public class HddPage{

        /**

         * Objeto que guarda y recupera trozos de cache de disco.

         */

        private ICacheDataSource[] dataSource = null;

        private int nPag = 0;

        /**

         * Constructor: crea un objeto dataSource.

         * @param nPag N?mero de p?gina

         * @param nBands N?mero de bandas del dataset

         * @throws RasterDriverException 

         * @throws NotSupportedExtensionException 

         * @throws FileNotFoundException 

         */

        public HddPage(int nPag, RasterDataset dataset, Extent extent) throws FileNotFoundException, NotSupportedExtensionException, RasterDriverException{

                this.nPag = nPag;

                dataSource = new CacheDataFromDriverServer[1];

                dataSource[0] = new CacheDataFromDriverServer(dataset, nPag, extent);        

        }

        /**

         * Constructor: crea un objeto dataSource para cada banda. Para todos los datasource de un 

         * mismo HddPage se usa el mismo identificador.

         * @param nPag N?mero de p?gina

         * @param nBands N?mero de bandas del dataset

         */

        public HddPage(int nPag, int nBands){

                this.nPag = nPag;

                dataSource = new CacheDataServer[nBands];

                for (int iBand = 0; iBand < nBands; iBand++)

                        dataSource[iBand] = new CacheDataServer(Long.toString(System.currentTimeMillis()), iBand, nPag);        

        }

        /**

         * Obtiene el servidor de datos de disco para una banda de la p?gina de

         * disco actual

         * @param nBand N?mero de banda

         * @return Servidor de datos de disco

         */

        public ICacheDataSource getDataServer(int nBand){

                if(nBand >= 0 && nBand < dataSource.length)

                        return dataSource[nBand];

                return null;

        }

        /**

         * Elimina una banda de la cach?. Antes salva a disco todos los trozos cacheados e inicializa

         * las estructuras de control de cach?. 

         * @param nBand N?mero de banda a eliminar

         * @throws IOException 

         */

        public void deleteBand(int nBand) throws IOException{

                if(nBand >= 0 && nBand < dataSource.length)

                        dataSource[nBand].delete();

        }

        /**

         * Asigna una banda de disco a todas las p?ginas.

         * @param cacheDataSource Fuente de las p?ginas. Es la referencia a disco de ellas.

         */

        public void assignBand(int nBand, ICacheDataSource cacheDataSource){

                if(nBand >= 0 && nBand < dataSource.length)

                        dataSource[nBand] = cacheDataSource;

        }

        /**

         * Obtiene la fuente de datos que corresponde a una banda.

         * @param nBand Banda a recuperar

         * @return ICacheDataSource 

         */

        public ICacheDataSource getBandDataSource(int nBand){

                return dataSource[nBand];

        }

}