A tool to migrate data from one cluster to another

You can comment on the code if you want. It is thrown together. I am most interested in parameter feedback. Do I have the right ones, etc?

    usage: bf-migrate
     -src                  [required] Source cassandra cluster
                           (host:port:keyspace)
     -dst <arg>            [required] Destination cassandra cluster
                           (host:port:keyspace)
     -cf <arg>             [required] Which column family to migrate
     -from <arg>           [optional] ISO 6801 datetime (or millis) of when to
                           start migrating data
     -to <arg>             [optional] ISO 6801 datetime (or millis) Datetime
                           of when to stop migrating data
     -limit <arg>          [optional] Maximum number of keys to process
     -skip <arg>           [optional] Number of keys to skip before processing
     -ttl <arg>            [optional] ttl in seconds for new data
     -writethreads <arg>   [optional] number of write threads to use
     -readthreads <arg>    [optional] number of read threads to use
     -batchsize <arg>      [optional] number of rows to read per query
     -verify               [optional] verify a sampling 0.5% of data copied
Is there a reason for doing the shutdown here, when it can be handled by the stagnation thread, just setting `stopAll` to true?