org.apache.spark.sql.execution.streaming.FlatMapGroupsWithStateExec
Returns the state as Java object if defined
Returns the row for an updated state
Returns the timeout timestamp of a state row is set
Set the timestamp in a state row
For every group, get the key, values and corresponding state and call the function, and return an iterator of rows
Find the groups that have timeout set and are timing out right now, and call the function
Helper class to update the state store