I'm using Spark 3.1.1 which uses Scala 2.12, and the pre-built Livy downloaded from here uses Scala 2.11 (one could find the folder named repl_2.11-jars/ after unzip).
Referred to the comment made by Aliaksandr Sasnouskikh, Livy needs to be rebuilt or it'll throw error {'msg': 'requirement failed: Cannot find Livy REPL jars.'} even in POST Session.
In the README.md, it mentioned:
By default Livy is built against Apache Spark 2.4.5
If I'd like to rebuild Livy, how could I change the spark version that it is built with?
Thanks in advance.