Registry for ListenableFutureCallback instances.
Inspired by com.google.common.util.concurrent.ExecutionList. API Doc
Extension of FutureTask that implements ListenableFuture. API Doc
whose value can be set via set(Object) or
setException(Throwable). It may also be cancelled.
Inspired by… API Doc
Defines the contract for success callbacks that accept the result of a
ListenableFuture. API Doc