/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.org
*
* (C) 2002-2008, Open Source Geospatial Foundation (OSGeo)
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation;
* version 2.1 of the License.
*
* This library 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
* Lesser General Public License for more details.
*/
package org.geotools.data.gen.info;
import java.io.File;
import java.io.IOException;
import java.net.URI;
import java.net.URL;
import java.net.URLDecoder;
import javax.xml.XMLConstants;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.validation.Schema;
import javax.xml.validation.SchemaFactory;
import javax.xml.validation.Validator;
import org.w3c.dom.Document;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;
/**
* @author Christian Mueller
*
* The default implementation for GeneralizationInfosProvider, reading the info from an XML file.
*
* The xml schema file is "/geninfos_1.0.xsd"
*
*
*
*
* @source $URL$
*/
public class GeneralizationInfosProviderImpl implements GeneralizationInfosProvider {
protected final static String GENERALIZATION_INFOS_TAG = "GeneralizationInfos";
protected final static String GENERALIZATION_INFO_TAG = "GeneralizationInfo";
protected final static String GENERALIZATION_TAG = "Generalization";
protected final static String FEATURE_NAME_ATTR = "featureName";
protected final static String BASE_FEATURE_NAME_ATTR = "baseFeatureName";
protected final static String GEOM_PROPERTY_NAME_ATTR = "geomPropertyName";
protected final static String DISTANCE_ATTR = "distance";
protected final static String DATASOURCE_NAME_ATTR = "dataSourceName";
protected final static String DATASOURCE_NAMESPACE_NAME_ATTR = "dataSourceNameSpace";
protected final static String VERSION_ATTR = "version";
protected static Validator VALIDATOR;
static {
SchemaFactory factory = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
URL url = GeneralizationInfosProviderImpl.class.getResource("/geninfos_1.0.xsd");
Schema schema = null;
try {
schema = factory.newSchema(url);
} catch (SAXException e) {
// should not happen
throw new RuntimeException(e);
}
VALIDATOR = schema.newValidator();
}
public GeneralizationInfos getGeneralizationInfos(Object source) throws IOException {
URL inputURL = deriveURLFromSourceObject(source);
GeneralizationInfos infos = parseXML(inputURL);
infos.validate();
return infos;
}
protected URL deriveURLFromSourceObject(Object source) throws IOException {
if (source == null)
throw new IOException("Cannot read from null");
if (source instanceof URL)
return (URL) source;
if (source instanceof String) {
URL url = null;
File f = new File((String) source);
if (f.exists())
url = f.toURI().toURL();
else
url = new URL((String) source);
url = new URL(URLDecoder.decode(url.toExternalForm(), "UTF8"));
return url;
}
if (source instanceof URI)
return ((URI) source).toURL();
return null;
}
protected GeneralizationInfos parseXML(URL url) throws IOException {
Document doc = null;
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
factory.setIgnoringComments(true);
factory.setNamespaceAware(true);
factory.setIgnoringElementContentWhitespace(true);
try {
DocumentBuilder db = factory.newDocumentBuilder();
doc = db.parse(url.openStream());
VALIDATOR.validate(new DOMSource(doc));
} catch (Exception e) {
throw new IOException(e.getMessage());
}
NodeList nl = doc.getElementsByTagName(GENERALIZATION_INFOS_TAG);
GeneralizationInfos gInfos = new GeneralizationInfos();
Node gInfosNode = nl.item(0);
checkVersion(gInfosNode);
NamedNodeMap attrMap = gInfosNode.getAttributes();
if (attrMap.getNamedItem(DATASOURCE_NAME_ATTR) != null)
gInfos.setDataSourceName(attrMap.getNamedItem(DATASOURCE_NAME_ATTR).getTextContent());
if (attrMap.getNamedItem(DATASOURCE_NAMESPACE_NAME_ATTR) != null)
gInfos.setDataSourceNameSpace(attrMap.getNamedItem(DATASOURCE_NAMESPACE_NAME_ATTR)
.getTextContent());
parseGeneralizationInfoNodes(gInfosNode, gInfos);
return gInfos;
}
protected void parseGeneralizationInfoNodes(Node parentNode, GeneralizationInfos gInfos) {
NodeList nl = parentNode.getChildNodes();
for (int i = 0; i < nl.getLength(); i++) {
Node generalisationInfoNode = nl.item(i);
if (GENERALIZATION_INFO_TAG.equals(generalisationInfoNode.getNodeName()) == false)
continue;
NamedNodeMap attrMap = generalisationInfoNode.getAttributes();
String baseFeatureName = attrMap.getNamedItem(BASE_FEATURE_NAME_ATTR).getTextContent();
String featureName = attrMap.getNamedItem(FEATURE_NAME_ATTR).getTextContent();
String geomPropertyName = null;
if (attrMap.getNamedItem(GEOM_PROPERTY_NAME_ATTR) != null)
geomPropertyName = attrMap.getNamedItem(GEOM_PROPERTY_NAME_ATTR).getTextContent();
GeneralizationInfo gi = new GeneralizationInfo(baseFeatureName, featureName,
geomPropertyName, gInfos);
if (attrMap.getNamedItem(DATASOURCE_NAME_ATTR) != null)
gi.setDataSourceName(attrMap.getNamedItem(DATASOURCE_NAME_ATTR).getTextContent());
if (attrMap.getNamedItem(DATASOURCE_NAMESPACE_NAME_ATTR) != null)
gi.setDataSourceNameSpace(attrMap.getNamedItem(DATASOURCE_NAMESPACE_NAME_ATTR)
.getTextContent());
parseDistanceInfoNodes(generalisationInfoNode, gi);
gInfos.addGeneralizationInfo(gi);
}
}
protected void parseDistanceInfoNodes(Node parentNode, GeneralizationInfo gInfo) {
NodeList nl = parentNode.getChildNodes();
for (int i = 0; i < nl.getLength(); i++) {
Node distanceInfoNode = nl.item(i);
if (GENERALIZATION_TAG.equals(distanceInfoNode.getNodeName()) == false)
continue;
NamedNodeMap attrMap = distanceInfoNode.getAttributes();
Double distance = new Double(attrMap.getNamedItem(DISTANCE_ATTR).getTextContent());
String featureName = attrMap.getNamedItem(FEATURE_NAME_ATTR).getTextContent();
String geomPropertyName = null;
if (attrMap.getNamedItem(GEOM_PROPERTY_NAME_ATTR) != null)
geomPropertyName = attrMap.getNamedItem(GEOM_PROPERTY_NAME_ATTR).getTextContent();
Generalization di = new Generalization(distance, featureName, geomPropertyName, gInfo);
if (attrMap.getNamedItem(DATASOURCE_NAME_ATTR) != null)
di.setDataSourceName(attrMap.getNamedItem(DATASOURCE_NAME_ATTR).getTextContent());
if (attrMap.getNamedItem(DATASOURCE_NAMESPACE_NAME_ATTR) != null)
di.setDataSourceNameSpace(attrMap.getNamedItem(DATASOURCE_NAMESPACE_NAME_ATTR)
.getTextContent());
gInfo.getGeneralizations().add(di);
}
}
protected void checkVersion(Node gInfos) throws IOException {
String version = gInfos.getAttributes().getNamedItem(VERSION_ATTR).getTextContent();
if ("1.0".equals(version) == false) {
throw new IOException(gInfos.getLocalName() + " " + version + " is not supported");
}
}
}