Skip unnecessary tags in osm

Open Source Routing Engine
#1

Please, tell me how to skip unnecessary tags when loading an OSM file?

    GraphHopper hopper = new GraphHopper();
    hopper.setOSMFile(ghLoc);
    hopper.setGraphHopperLocation("target/routing-graph-cache");
    hopper.setProfiles(new Profile("car").setVehicle("car").setWeighting("fastest").setTurnCosts(false));
    hopper.getCHPreparationHandler().setCHProfiles(new CHProfile("car"));
    hopper.importOrLoad();
    return hopper;
#2

The OSM file is read once and converted into a custom data (“routing graph”) and only data necessary for the routing is stored.

#3

Okay, I understand. What should I do if I only need one tag ‘railway=rail’ when loading the OSM data?

#4

You mean you only want to keep OSM ways that are tagged as railway=rail? Which OSM ways are kept during the import is defined by this function: graphhopper/OSMReader.java at 78fe44aa758e9847ef95f71d18ffa70d125a14a3 · graphhopper/graphhopper · GitHub