Class MonotonicSystemClock

    • Field Summary

      Fields 
      Modifier and Type Field Description
      private static java.util.concurrent.atomic.AtomicLong before  
    • Field Detail

      • before

        private static final java.util.concurrent.atomic.AtomicLong before
    • Constructor Detail

      • MonotonicSystemClock

        public MonotonicSystemClock()
    • Method Detail

      • nowMicros

        private static long nowMicros()
      • propose

        public ProposedTimestamp propose()
        Obtain a timestamp close to "now".

        Proposed times are close to "now", but may not yet be certainly in the past. This allows the calling thread to interleave other useful work while waiting for the clock instance to create an assurance it will never in the future propose a time earlier than the returned time.

        A hypothetical implementation could read the local system clock (managed by NTP) and return that proposal, concurrently sending network messages to closely collaborating peers in the same cluster to also ensure their system clocks are ahead of this time. In such an implementation the ProposedTimestamp.blockUntil(Duration) method would wait for replies from the peers indicating their own system clocks have moved past the proposed time.

        Specified by:
        propose in interface MonotonicClock
        Returns:
        a ProposedTimestamp object.