Class NanoWatch

java.lang.Object
fc.util.Watch
fc.util.NanoWatch
public final class NanoWatch extends Watch
Allows measuring the start and stop time and (hence the elapsed time) of some event. ("event" meaning something of interest, for example, a method call). Can be started/stopped repeatedly. (cumulative time across all such start/stops are available via the cumulativeTime() method).

All times are in nano-seconds.

Thread Safety: This class is not threadsafe and it's method do not acquire any locks to reduce any time skew due to lock acquisition. Multiple threads should use separate NanoWatch objects or alternatively, higher level synchronization.

See Also:

  • Constructor Details

  • Method Details

    • start

      public NanoWatch start()
      Start measuring time. Call this method just before calling the method/code to be instrumented. This method does not reset the Watch, so the reset method should be called before calling this method again.
      Overrides:
      start in class Watch

    • stop

      public void stop()
      Stop measuring the time
      Overrides:
      stop in class Watch

    • time

      public long time()
      Returns the time elapsed since the Watch was started. If the watch was started and stopped, returns the time between the start/stop interval.
      Overrides:
      time in class Watch
      Throws:
      RuntimeException - if the watch was never started before calling this method.

    • getTime

      public long getTime()
      Returns the time elapsed since the Watch was started. (this method is an alias for time() method).
      Overrides:
      getTime in class Watch

    • getTimeInMillis

      public double getTimeInMillis()
      Returns the elapsed time in milliseconds. Useful when nanosecond values are too hard to read.
      Overrides:
      getTimeInMillis in class Watch

    • cumulativeTime

      public long cumulativeTime()
      Returns the total time recorded by this Watch (across several starts/stops)
      Overrides:
      cumulativeTime in class Watch

    • reset

      public void reset()
      Reset all values to zero. This method should be called before this object is used again.
      Overrides:
      reset in class Watch

    • isRunning

      public boolean isRunning()
      Is the Watch currently running ?
      Overrides:
      isRunning in class Watch

    • toString

      public String toString()
      Description copied from class: Watch
      Describes the current state of this watch. The exact details of said description are unspecified and subject to change.
      Overrides:
      toString in class Watch

    • main

      public static void main(String[] args)