001    // License: GPL. For details, see LICENSE file.
002    package org.openstreetmap.josm.io.session;
003    
004    import static org.openstreetmap.josm.tools.I18n.tr;
005    
006    import java.io.IOException;
007    import java.io.InputStream;
008    
009    import javax.xml.xpath.XPath;
010    import javax.xml.xpath.XPathConstants;
011    import javax.xml.xpath.XPathExpression;
012    import javax.xml.xpath.XPathExpressionException;
013    import javax.xml.xpath.XPathFactory;
014    
015    import org.w3c.dom.Element;
016    
017    import org.openstreetmap.josm.gui.layer.Layer;
018    import org.openstreetmap.josm.gui.progress.ProgressMonitor;
019    import org.openstreetmap.josm.io.IllegalDataException;
020    import org.openstreetmap.josm.io.OsmImporter;
021    import org.openstreetmap.josm.io.session.SessionReader.ImportSupport;
022    
023    public class OsmDataSessionImporter implements SessionLayerImporter {
024    
025        @Override
026        public Layer load(Element elem, ImportSupport support, ProgressMonitor progressMonitor) throws IOException, IllegalDataException {
027            String version = elem.getAttribute("version");
028            if (!"0.1".equals(version)) {
029                throw new IllegalDataException(tr("Version ''{0}'' of meta data for osm data layer is not supported. Expected: 0.1", version));
030            }
031            try {
032                XPathFactory xPathFactory = XPathFactory.newInstance();
033                XPath xpath = xPathFactory.newXPath();
034                XPathExpression fileExp = xpath.compile("file/text()");
035                String fileStr = (String) fileExp.evaluate(elem, XPathConstants.STRING);
036                if (fileStr == null || fileStr.equals("")) {
037                    throw new IllegalDataException(tr("File name expected for layer no. {0}", support.getLayerIndex()));
038                }
039    
040                OsmImporter importer = new OsmImporter();
041                InputStream in = support.getInputStream(fileStr);
042                OsmImporter.OsmImporterData importData = importer.loadLayer(in, support.getFile(fileStr), support.getLayerName(), progressMonitor);
043    
044                support.addPostLayersTask(importData.getPostLayerTask());
045                return importData.getLayer();
046    
047            } catch (XPathExpressionException e) {
048                throw new RuntimeException(e);
049            }
050        }
051    }
052