From the changes in , it is now no longer possible from the outside to specify a 'null' localDC when creating a DCAwareRoundRobinPolicy and have it figured out the localDC based on contact points, however the documentation states that this functionality still works:
localDc - the name of the local datacenter (as known by Cassandra). If this is null, the policy will default to the data-center of the first node connected to.
Passing in a null localDC parameter emits the following error:
with the following code:
Additionally, A user could use the default Constructor for DCAwareRoundRobinPolicy to use the DC the contact points are in, but if they want to control the usedRemoteHostsPerDc / allowRemoteDCsForLocalConsistencyLevel options, they cannot. It seems like we should be able to support this, ( will take care of this).