001// License: GPL. For details, see LICENSE file.
002package org.openstreetmap.josm.io;
003
004import org.openstreetmap.josm.data.osm.OsmPrimitiveType;
005import org.openstreetmap.josm.gui.preferences.server.OverpassServerPreference;
006import org.openstreetmap.josm.tools.Utils;
007
008import java.util.Set;
009
010/**
011 * Retrieves a set of {@link org.openstreetmap.josm.data.osm.OsmPrimitive}s from an Overpass API server.
012 *
013 * @since 9241
014 */
015class MultiFetchOverpassObjectReader extends MultiFetchServerObjectReader {
016
017    @Override
018    protected String buildRequestString(final OsmPrimitiveType type, Set<Long> idPackage) {
019        final Utils.Function<Long, Object> toOverpassExpression = new Utils.Function<Long, Object>() {
020            @Override
021            public Object apply(Long x) {
022                return type.getAPIName() + "(" + x + ");>;";
023            }
024        };
025        final String query = "(" + Utils.join("", Utils.transform(idPackage, toOverpassExpression)) + ");out meta;";
026        return "interpreter?data=" + Utils.encodeUrl(query);
027    }
028
029    @Override
030    protected String getBaseUrl() {
031        return OverpassServerPreference.getOverpassServer();
032    }
033
034    @Override
035    protected boolean recursesDown() {
036        // see https://wiki.openstreetmap.org/wiki/Overpass_API/Overpass_QL#Recurse_down_.28.3E.29 for documentation
037        // accomplished using >; in the query string above
038        return true;
039    }
040}