A timestamp generator based on
System.currentTimeMillis(), with an incrementing atomic counter
to generate the sub-millisecond part.
This implementation guarantees incrementing timestamps among all client threads, provided that no more than
1000 are requested for a given clock tick (the exact granularity of of
System.currentTimeMillis()
depends on the operating system).
If that rate is exceeded, a warning is logged and the timestamps don't increment anymore until the next clock
tick. If you consistently exceed that rate, consider using
ThreadLocalMonotonicTimestampGenerator.