To generate an artifact for a different spark version and/or scala version, pass command-line options as follows (changing version numbers appropriately):
$ mvn -Dspark.version=2.2.2 -Dscala.version=2.11.7 -Dscala.binary.version=2.11 clean install
To build the connector with Spark 3.0, compile it with scala 2.12. Additional configurations that you can customize are the Spark version, HBase version, and Hadoop version. Example:
$ mvn -Dspark.version=3.0.1 -Dscala.version=2.12.10 -Dscala.binary.version=2.12 -Dhbase.version=2.2.4 -Dhadoop.profile=3.0 -Dhadoop-three.version=3.2.0 -DskipTests clean package