| gvSIG desktop 1

/**********************************************************************

 * $Id$

 *

 * Name:     MrSIDImageReader.java

 * Project:  JMRSID. Interfaz java to MrSID (Lizardtech).

 * Purpose:

 * Author:   Nacho Brodin, brodin_ign@gva.es

 *

 **********************************************************************/

/*Copyright (C) 2004  Nacho Brodin <brodin_ign@gva.es>

 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.

 [01] 01-Oct-2005 nbt New call to JNI function MrSIDImageReaderArrayNat to convert name string to char array.

 */

package es.gva.cit.jmrsid;

import java.io.File;

import java.io.IOException;

/**

 *

 * @author Nacho Brodin <brodin_ign@gva.es>.<BR> Equipo de desarrollo gvSIG.<BR> http://www.gvsig.gva.es

 * @version 0.0

 * @link http://www.gvsig.gva.es

 */

public class MrSIDImageReader extends MrSIDImageReaderBase{

        private native long MrSIDImageReaderNat(String pszFilename);

        private native long MrSIDImageReaderArrayNat(byte[] b);

        private native void FreeMrSIDImageReaderNat(long cPtr);

        public MrSIDImageReader(){}

        /**

         * Constructor

         * @param cPtr        direcci?n de memoria al objeto MrSIDImageReader de C.

         */

        public MrSIDImageReader(long cPtr){

                this.cPtr=cPtr;

        }

        /**

         * Destructor

         */

        protected void finalize(){

                this.close();

        }

        /**

         * Cierra el MrSIDImageReader

         *

         */

        public void close(){

                if(cPtr > 0){

                        FreeMrSIDImageReaderNat(cPtr);

                        cPtr = -1;

                }

        }

        /**

         * Constructor

         *

         * @param pszFilename        Nombre del fichero

         * @throws MrSIDException, IOException

         */

        public MrSIDImageReader(String pszFilename)throws MrSIDException, IOException{

                File f = new File( pszFilename );

                if(!f.exists())

                        throw new IOException("The file "+pszFilename+" don't exists");

                if(!f.canRead())

                        throw new IOException("I can't read the file");

                cPtr=MrSIDImageReaderArrayNat(pszFilename.getBytes());

                if(cPtr<0)

                        throw new MrSIDException("Error in MrDID Open");

        }

        /**

         * Obtiene el n?mero de niveles

         */

        public int getNumLevels()throws MrSIDException{

                String os = System.getProperty("os.name").toLowerCase();

                if(os.startsWith("mac os x")){

                        return getNumLevelsFromMinMagnification();

                }else{

                        String msg1="Error en getNumLevels. No se ha obtenido un puntero valido a LTIImage";

                        String msg2="La llamada nativa a getNumLevels ha devuelto un c?digo de error";

                        return baseSimpleFunction(2,msg1,msg2);

                }

        }

        /**

         * Obtiene el n?mero de niveles s partir de getMinMagnification.

         * (Funcion creada para Mac sobre Power PC por los problemas con getNumLevels)

         */

        public int getNumLevelsFromMinMagnification()throws MrSIDException{

                double mag = getMinMagnification();

                   double aux = getWidth() * mag;

                   int cont = 0;

                   while(aux < getWidth()){

                           aux *= 2;

                           cont ++;

                   }

                return cont;

        }

}