Application: gvSIG desktop

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package org.gvsig.xml2db.lib.impl;

import java.io.File;

import java.io.FileNotFoundException;

import java.io.IOException;

import java.io.InputStream;

import java.io.Reader;

import java.nio.charset.Charset;

import java.util.ArrayList;

import java.util.List;

import javax.xml.parsers.SAXParser;

import javax.xml.parsers.SAXParserFactory;

import org.apache.commons.lang3.StringUtils;

import org.apache.commons.lang3.mutable.MutableObject;

import org.cresques.cts.IProjection;

import org.gvsig.fmap.crs.CRSFactory;

import org.gvsig.fmap.dal.DALLocator;

import org.gvsig.fmap.dal.DataManager;

import org.gvsig.tools.ToolsLocator;

import org.gvsig.tools.i18n.I18nManager;

import org.gvsig.tools.task.SimpleTaskStatus;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.xml.sax.Attributes;

import org.xml.sax.InputSource;

import org.xml.sax.Locator;

import org.xml.sax.SAXException;

import org.xml.sax.helpers.DefaultHandler;

/**

 *

 * @author jjdelcerro

 */

public class ProjectionExtractorImpl {

    private static final Logger LOGGER = LoggerFactory.getLogger(ProjectionExtractorImpl.class);

    private static class ProjectionExtractorException extends RuntimeException {

    }

    private IProjection extractProjection(InputSource is, SimpleTaskStatus status) {

        if( is == null || is.getCharacterStream() == null ) {

            throw new IllegalArgumentException("input source is null");

        }

        MutableObject<IProjection> proj = new MutableObject<>();

        try {

            final DataManager dataManager = DALLocator.getDataManager();

            I18nManager i18n = ToolsLocator.getI18nManager();

            status.message(i18n.getTranslation("_Reading_xml"));

            status.setIndeterminate();

            SAXParserFactory spf = SAXParserFactory.newInstance();

            spf.setNamespaceAware(true);

            SAXParser saxParser = spf.newSAXParser();

            List<String> path = new ArrayList<>();

            saxParser.parse(is, new DefaultHandler() {

                private Locator locator;

                int size;

                int refreshInterval = 1;

                StringBuilder chars = new StringBuilder();

                @Override

                public void setDocumentLocator(Locator locator) {

                    this.locator = locator;

                }

                @Override

                public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {

                    for (int i = 0; i < attributes.getLength(); i++) {

                        String name = attributes.getLocalName(i);                        

                        String value = attributes.getValue(i);

                        if( StringUtils.containsIgnoreCase(name, "srid") ) {

                            proj.setValue(getProjection(value));

                            if( proj.getValue() !=null ) {

                                throw new ProjectionExtractorException();

                            }

                        }

                    }

                    chars.setLength(0);

                }

                @Override

                public void endElement(String uri, String localName, String qName) throws SAXException {

                    String value = this.chars.toString();

                    if (StringUtils.containsIgnoreCase(localName, "srid")) {

                        proj.setValue(getProjection(value));

                        if (proj.getValue() != null) {

                            throw new ProjectionExtractorException();

                        }

                    }

                    chars.setLength(0);

                }

                @Override

                public void characters(char[] ch, int start, int length) throws SAXException {

                    this.chars.append(ch, start, length);

                }

            });

            return null;

        } catch (ProjectionExtractorException ex) {

            return proj.getValue();

        } catch (Exception ex) {

            throw new RuntimeException("Can't extract projection.", ex);

        }

    }

    private IProjection getProjection(String value) {

        if( StringUtils.isBlank(value) ) {

            return null;

        }

        IProjection proj = null;

        try {

            proj = CRSFactory.getCRS(value);

        } catch(Throwable t) {

        }

        if( proj != null ) {

            return proj;

        }

        try {

            proj = CRSFactory.getCRS("EPSG:"+value);

        } catch(Throwable t) {

        }

        return proj;

    }

    public IProjection extractProjection(File xml, Charset charset, SimpleTaskStatus status) {

        InputSource is = Xml2dbCommons.openReader(xml,charset);

        return extractProjection(is, status);

    }

    public IProjection extractProjection(InputStream xml, Charset charset, SimpleTaskStatus status)  {

        InputSource is = Xml2dbCommons.openReader(xml, charset);

        return extractProjection(is, status);

    }

    public IProjection extractProjection(Reader reader, SimpleTaskStatus status) {

        InputSource is = new InputSource(reader);

        return extractProjection(is, status);

    }

}