I've used it as the backing for a time-series database and to store deltas for a state-machine - in both situations I wanted something that understood "POJOs" a

I've used it as the backing for a time-series database and to store deltas for a state-machine - in both situations I wanted something that understood "POJOs" and didn't require a lot of setup. Even in the case of multiple non-unique entries, if the stored objects are not meant to be mutable, the API exposes .reverse() to find the most recent.