@rogargon I tried to reconstruct the exception you got, but with no success.
my Java Version: 1.8.0_292
Initially I used Maven 3.3.9, but I switched to 3.8.1 to see if that works too, and it does. I also deleted my maven .m2 folder to see if maven downloads all the dependencies correctly.
Did you mvn clean install first? Otherwise some dependencies may are missing for you.
Apart of that I made minor changes, because there was an issue with the handling of Collection Queries. The following commands work fine for me now.
git clone https://github.com/dbpedia/databus-client.git
cd databus-client
mvn clean install
./bin/DatabusClient -s "https://databus.dbpedia.org/rogargon/collections/browsable_core"
Another approach would be to use the released jar file of the DBpedia Databus-Client. Have you tried that already? It works out of the box, no maven commands needed. You can download it here:
The command for execution would be:
java -jar databus-client-1.0-SNAPSHOT.jar -s "https://databus.dbpedia.org/rogargon/collections/browsable_core"