001// License: GPL. For details, see LICENSE file.
002package org.openstreetmap.josm.gui.dialogs.relation;
003
004import static org.openstreetmap.josm.tools.I18n.tr;
005
006import java.io.IOException;
007import java.lang.reflect.InvocationTargetException;
008import java.util.Collection;
009
010import javax.swing.SwingUtilities;
011
012import org.openstreetmap.josm.Main;
013import org.openstreetmap.josm.data.osm.DataSet;
014import org.openstreetmap.josm.data.osm.DataSetMerger;
015import org.openstreetmap.josm.data.osm.Relation;
016import org.openstreetmap.josm.gui.DefaultNameFormatter;
017import org.openstreetmap.josm.gui.ExceptionDialogUtil;
018import org.openstreetmap.josm.gui.PleaseWaitRunnable;
019import org.openstreetmap.josm.gui.layer.OsmDataLayer;
020import org.openstreetmap.josm.io.OsmServerObjectReader;
021import org.openstreetmap.josm.io.OsmTransferException;
022import org.openstreetmap.josm.tools.CheckParameterUtil;
023import org.xml.sax.SAXException;
024
025/**
026 * The asynchronous task for fully downloading a collection of relations. Does a full download
027 * for each relations and merges the relation into an {@link OsmDataLayer}
028 *
029 */
030public class DownloadRelationTask extends PleaseWaitRunnable {
031    private boolean canceled;
032    private Exception lastException;
033    private final Collection<Relation> relations;
034    private final OsmDataLayer layer;
035    private OsmServerObjectReader objectReader;
036
037    /**
038     * Creates the download task
039     *
040     * @param relations a collection of relations. Must not be null.
041     * @param layer the layer which data is to be merged into
042     * @throws IllegalArgumentException if relations is null
043     * @throws IllegalArgumentException if layer is null
044     */
045    public DownloadRelationTask(Collection<Relation> relations, OsmDataLayer layer) {
046        super(tr("Download relations"), false /* don't ignore exception */);
047        CheckParameterUtil.ensureParameterNotNull(relations, "relations");
048        CheckParameterUtil.ensureParameterNotNull(layer, "layer");
049        this.relations = relations;
050        this.layer = layer;
051    }
052
053    @Override
054    protected void cancel() {
055        canceled = true;
056        synchronized (this) {
057            if (objectReader != null) {
058                objectReader.cancel();
059            }
060        }
061    }
062
063    @Override
064    protected void finish() {
065        if (canceled)
066            return;
067        if (lastException != null) {
068            ExceptionDialogUtil.explainException(lastException);
069        }
070    }
071
072    @Override
073    protected void realRun() throws SAXException, IOException, OsmTransferException {
074        try {
075            final DataSet allDownloads = new DataSet();
076            int i = 0;
077            getProgressMonitor().setTicksCount(relations.size());
078            for (Relation relation: relations) {
079                i++;
080                getProgressMonitor().setCustomText(tr("({0}/{1}): Downloading relation ''{2}''...", i, relations.size(),
081                        relation.getDisplayName(DefaultNameFormatter.getInstance())));
082                synchronized (this) {
083                    if (canceled) return;
084                    objectReader = new OsmServerObjectReader(relation.getPrimitiveId(), true /* full download */);
085                }
086                DataSet dataSet = objectReader.parseOsm(
087                        getProgressMonitor().createSubTaskMonitor(0, false)
088                );
089                if (dataSet == null)
090                    return;
091                synchronized (this) {
092                    if (canceled) return;
093                    objectReader = null;
094                }
095                DataSetMerger merger = new DataSetMerger(allDownloads, dataSet);
096                merger.merge();
097                getProgressMonitor().worked(1);
098            }
099
100            SwingUtilities.invokeAndWait(
101                    new Runnable() {
102                        @Override
103                        public void run() {
104                            layer.mergeFrom(allDownloads);
105                            layer.onPostDownloadFromServer();
106                            Main.map.repaint();
107                        }
108                    }
109            );
110        } catch (OsmTransferException | InvocationTargetException | InterruptedException e) {
111            if (canceled) {
112                Main.warn(tr("Ignoring exception because task was canceled. Exception: {0}", e.toString()));
113                return;
114            }
115            lastException = e;
116        }
117    }
118}