Hi Sai,

This exception is not really related to this thread.

JanusGraph with SparkGraphComputer can only be used with the TinkerPop HadoopGraph. Therefore, the example in the JanusGraph ref docs has a properties file starting with the following lines:

gremlin.graph=org.apache.tinkerpop.gremlin.hadoop.structure.HadoopGraph
gremlin.hadoop.graphReader=org.janusgraph.hadoop.formats.cassandra.Cassandra3InputFormat

Some of the other JanusGraph storage backends have their own InputFormat.
If you encounter other problems please include the properties file and calling code.

Best wishes,    Marc