Application: gvSIG desktop » gvSIG raster

/* gvSIG. Geographic Information System of the Valencian Government

 *

 * Copyright (C) 2007-2008 Infrastructures and Transports Department

 * of the Valencian Government (CIT)

 *

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

 * MA  02110-1301, USA.

 *

 */

package org.gvsig.raster.impl.datastruct.serializer;

import java.io.IOException;

import java.io.Reader;

import java.io.StringReader;

import org.gvsig.fmap.dal.coverage.dataset.Buffer;

import org.gvsig.fmap.dal.coverage.exception.ParsingException;

import org.gvsig.raster.impl.datastruct.DefaultNoData;

import org.gvsig.raster.impl.store.rmf.ClassSerializer;

import org.gvsig.tools.ToolsLocator;

import org.gvsig.tools.extensionpoint.ExtensionPoint;

import org.gvsig.tools.extensionpoint.ExtensionPointManager;

import org.kxml2.io.KXmlParser;

import org.xmlpull.v1.XmlPullParserException;

/**

 * <P>

 * This object converts a nodata value to XML. This class implements an IRmfBlock

 * interface with the method to read and write. These will be used by the RMF file

 * manager to read and write data.  

 * </P>

 * <P>

 * A raster will have a nodata value by band and its structure will be something like that:

 * </P>

 * <P>

 * \<NoDataValue datatype=3 transparent=true\><BR>

 * &nbsp;\<Band number=0 value=-99999 \><BR>

 * &nbsp;\<Band number=1 value=-99999 \><BR>

 * &nbsp;\<Band number=2 value=-99999 \><BR>

 * \</NoDataValue\><BR>

 *

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

 */

public class NoDataRmfSerializer extends ClassSerializer {

        private final String MAIN_TAG = "NoDataValue";

        private DefaultNoData noData = null;

        /**

         * Registra NoDataRmfSerializer en los puntos de extension de Serializer

         */

        public static void register() {

                ExtensionPointManager extensionPoints = ToolsLocator.getExtensionPointManager();

                ExtensionPoint point = extensionPoints.get("Serializer");

                point.append("NoDataValue", "", NoDataRmfSerializer.class);

        }

        /**

         * Sets the nodata value to serialize

         * @param noData   Valor NoData

         */

        public NoDataRmfSerializer(DefaultNoData noData) {

                this.noData = noData;

        }

        /**

         * Constructor.

         */

        public NoDataRmfSerializer() {}

        public String getMainTag() {

                return MAIN_TAG;

        }

        /**

         * Devuelve el valor noData, en caso de no existir lo crea.

         * @return

         */

        private DefaultNoData getNoData() {

                if (noData == null)

                        noData = new DefaultNoData();

                return noData;

        }

        public Object getResult() {

                return noData;

        }

        public void read(String xml) throws ParsingException {

                KXmlParser parser = new KXmlParser();

                Reader reader = new StringReader(xml);

                try {

                        parser.setInput(reader);

                } catch (XmlPullParserException e) {

                        throw new ParsingException(xml);

                }

                getNoData().delete();

                int bands = 0;

                try {

                        int tag = parser.nextTag();

                        if (parser.getEventType() != KXmlParser.END_DOCUMENT) {

                                parser.require(KXmlParser.START_TAG, null, MAIN_TAG);

                                for (int i = 0; i < parser.getAttributeCount(); i++) {

                                        if (parser.getAttributeName(i).equals("transparent")) {

                                                getNoData().setNoDataTransparent(new Boolean(parser.getAttributeValue(i)));

                                        }

                                        if (parser.getAttributeName(i).equals("datatype")) {

                                                getNoData().setDataType(new Integer(parser.getAttributeValue(i)));

                                        }

                                }

                                while (tag != KXmlParser.END_DOCUMENT) {

                                        switch (tag) {

                                                case KXmlParser.START_TAG:

                                                        if (parser.getName().equals("Band")) {

                                                                bands ++;

                                                                for (int i = 0; i < parser.getAttributeCount(); i++) {

                                                                        if (parser.getAttributeName(i).equals("value")) {

                                                                                String str = (String) parser.getAttributeValue(i);

                                                                                if(str.compareTo("null") == 0)

                                                                                        getNoData().setValue(null);

                                                                                else

                                                                                        getNoData().setValue(Double.parseDouble(str));

                                                                        }

                                                                }

                                                        }

                                        }

                                        tag = parser.next();

                                }

                        }

                        reader.close();

                        getNoData().setBandCount(bands);

                } catch (XmlPullParserException e) {

                        throw new ParsingException(xml);

                } catch (IOException e) {

                        throw new ParsingException(xml);

                }

        }

        public String write() throws IOException {

                if (noData == null)

                        return "";

                StringBuffer b = new StringBuffer();

                b.append("<" + MAIN_TAG + " datatype=\"" + getNoData().getDataType() + "\" transparent=\"" + getNoData().isNoDataTransparent() + "\">\n");

                for (int i = 0; i < getNoData().getBandCount(); i++) {

                        Number value = getNoData().getValueByBand(i);

                        b.append("\t<Band");

                        b.append(" number=\"" + i + "\"");

                        if(value != null) {

                                switch (getNoData().getDataType()) {

                                case Buffer.TYPE_BYTE:

                                        b.append(" value=\"" + value.byteValue() + "\"/>\n");

                                        break;

                                case Buffer.TYPE_SHORT:

                                        b.append(" value=\"" + value.shortValue() + "\"/>\n");

                                        break;

                                case Buffer.TYPE_INT:

                                        b.append(" value=\"" + value.intValue() + "\"/>\n");

                                        break;

                                case Buffer.TYPE_FLOAT:

                                        b.append(" value=\"" + value.floatValue() + "\"/>\n");

                                        break;

                                case Buffer.TYPE_DOUBLE:

                                        b.append(" value=\"" + value.doubleValue() + "\"/>\n");

                                        break; 

                                }

                        } else {

                                b.append(" value=\"null\"/>\n");

                        }

                }

                b.append("</" + MAIN_TAG + ">\n");

                return b.toString();

        }

}