Error accessing transitive dependencies via %maven

So I am working on the DFLib Jupyter integration per https://github.com/nhl/dflib/issues/44 . It mostly works well. Found one problem though. I am including all the DFLib modules as “compile” dependencies of “dflib-jupyter” , so I assumed I can only specify %maven com.nhl.dflib:dflib-jupyter:0.6-SNAPSHOT once, and get all of them. Apparently not. Here is a screenshot where Jupyter fails to import a package from one of the dependencies:

Oddly enough, when instead of importing “com.nhl.dflib”, I import “com.nhl.dflib.jdbc” package (from another module), the error is NoClassDefFound on the core DFLib package… So it seems to be ok with jdbc import, but still can’t find the core library.

[andrus]

School has taken priority as of lately and as a result I haven’t had much free time to work on IJava and friends other than try and keep up with replying to issues. So please don’t take the recent lack of progress as lack of interest in maintaining the project.

No worries. As a long time open source developer I can relate.

Could you try marking the basekernel with the provided scope?

This solved the second issue - the conflict between 2 notebooks. It no longer appears.

[karussell]

Thanks for providing this nice tool. I also got my small Java test working, but stumble over a very similar problem that is described here when doing the following:

%maven com.graphhopper:graphhopper-core:1.0
%maven com.graphhopper:graphhopper-reader-osm:1.0
%maven com.carrotsearch:hppc:0.8.1
%maven org.slf4j:slf4j-api:1.7.30
%maven org.slf4j:slf4j-log4j12:1.7.30
%maven log4j:log4j:1.2.17

import com.graphhopper.*;
import com.graphhopper.config.*;
import com.graphhopper.util.*;
import com.graphhopper.reader.osm.*;
import com.graphhopper.routing.util.*;

if(!new File("osm.pbf").exists()) {
  System.out.println("download OpenStreetMap data ...");
  new Downloader("GraphHopper Downloader").downloadFile("http://download.geofabrik.de/europe/germany/berlin-latest.osm.pbf", "osm.pbf");
}

System.out.println("start importOrLoad ...");
GraphHopper hopper = new GraphHopperOSM().
    setOSMFile("osm.pbf").
    setProfiles(Collections.singletonList(new Profile("car").setVehicle("car").setWeighting("fastest"))).
    setEncodingManager(EncodingManager.create("car")).
    setGraphHopperLocation("graph-cache").
    importOrLoad();

GHResponse rsp = hopper.route(new GHRequest(52.532932,13.341522, 52.503684,13.404694).setProfile("car"));
if(rsp.hasErrors())
    throw new RuntimeException(rsp.getErrors().get(0));
ResponsePath best = rsp.getBest();
System.out.println("distance " + best.getDistance());

I sometimes get errors that a certain class is missing although it should be included from one of the %maven statements. E.g.:

java.lang.NoClassDefFoundError: org/apache/log4j/Level

or

java.lang.NoClassDefFoundError: com/carrotsearch/hppc/IntLookupContainer

or

java.lang.IllegalStateException: org.slf4j.LoggerFactory in failed state. Original exception was thrown EARLIER. See also http://www.slf4j.org/codes.html#unsuccessfulInit
	at org.slf4j.LoggerFactory.getILoggerFactory(LoggerFactory.java:427)

Sometimes it affects the last %maven statement. Not sure if it helps but this was (sometimes) reproducible at mybinder.org.

And one time I was able to remove such an error when I switched from %%loadFromPOM to %maven but it does not disappear now and is also permanent even if I restart my system. Is there a way to “restart from scratch”?