Here is my use case -- I would like to use the DistributedMapCache to cache about 30k records that I read from an http service. Once per day, I'd like to update the cache, which includes removing items which are no longer returned by the http service. I had wanted to implement this by writing a custom processor to retrieve the list of keys from the DistributedMapCache, and remove any item which did not get returned by the http service. However, when I looked at the interface for DistributedMapCacheClient, the method to return the set of keys (keySet) throws the UnsupportedOperationException. Does anyone have any suggestions on how else I can implement this? I'm a newbie with NiFi -- any suggestions you have would be greatly appreciated! Thanks! ... View more