// Always invoke the TransactionMapWrapperCallback to let somebody know that
// we finished the MAP phase at this partition
TransactionMapWrapperCallback callback = mr_ts.getTransactionMapWrapperCallback();
assert (callback != null) : "Unexpected null callback for " + mr_ts;
assert (callback.isInitialized()) : "Unexpected uninitalized callback for " + mr_ts;
callback.run(this.partitionId);
}
// ----------------------------------------------------------------------------
// REDUCE PHASE
// ----------------------------------------------------------------------------