It's not outdated, but sometimes people use the jar that was built for Scala 2.12 when they are running Scala 2.13. Also as I mentioned in my earlier comment, make sure that you don't have mixed ...

Save XGBoost model to HDFS with both scala and python XGBoost API, and get the following errors: Python API Traceback (most recent call last): File "train.py", line 65, in <module> best_model.save_ ...