The DefaultDatumQueue currently uses a DelayQueue to process all datum. This design choice was made when the queue was implemented as an EventHandler and encountered "duplicate" datum from "captured" and "acquired" events. Version 2 of DefaultDatumQueue dropped the event-based approach however, and now datum are explicitly added to the queue, so there are no duplicates.

 

As a consequence, the current use of DelayQueue is unnecessary, and the simplier PriorityBlockingQueue could be used instead.