Package com.apple.foundationdb

Interface EventKeeper

All Known Implementing Classes:

MapEventKeeper

public interface EventKeeper

A device for externally instrumenting the FDB java driver, for monitoring purposes. Note that implementations as expected to be thread-safe, and may be manipulated from multiple threads even in nicely single-threaded-looking applications.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static interface	EventKeeper.Event	Marker interface for tracking the specific type of event that occurs, and metadata about said event.
static class	EventKeeper.Events	An enumeration of static events which occur within the FDB Java driver.

Method Summary

Modifier and Type	Method	Description
void	count(EventKeeper.Event event, long amt)	Count the number of events which occurred.
long	getCount(EventKeeper.Event event)	Get the number of events which occurred since this timer was created.
default long	getTime(EventKeeper.Event event, java.util.concurrent.TimeUnit theUnit)	Get the amount of time taken by this event, in the specified units.
long	getTimeNanos(EventKeeper.Event event)	Get the amount of time taken by this event, in nanoseconds.
default void	increment(EventKeeper.Event event)	Convenience method to add 1 to the number of events which occurred.
default void	time(EventKeeper.Event event, long duration, java.util.concurrent.TimeUnit theUnit)	Count the time taken to perform an action, in the specified units.
void	timeNanos(EventKeeper.Event event, long nanos)	Count the time taken to perform an event, in nanoseconds.

Method Detail

count

void count(EventKeeper.Event event,
           long amt)

Count the number of events which occurred.

Parameters:

event - the event which occurred

amt - the number of times that even occurred

increment

default void increment(EventKeeper.Event event)

Convenience method to add 1 to the number of events which occurred.

Parameters:

event - the event which occurred.

timeNanos

void timeNanos(EventKeeper.Event event,
               long nanos)

Count the time taken to perform an event, in nanoseconds. Note that event.isTimeEvent() should return true here.

Parameters:

event - the event which was timed (the event should be a time event).

nanos - the amount of time taken (in nanoseconds)

time

default void time(EventKeeper.Event event,
                  long duration,
                  java.util.concurrent.TimeUnit theUnit)

Count the time taken to perform an action, in the specified units. Note that event.isTimeEvent() should return true.

Parameters:

event - the event which was timed.

duration - the time taken

theUnit - the unit of time in which the time measurement was taken

getCount

long getCount(EventKeeper.Event event)

Get the number of events which occurred since this timer was created. If the event was never recorded, then this returns 0.

Parameters:

event - the event to get the count for

Returns:

the number of times the event was triggered. If the event has never been triggered, then this returns 0

getTimeNanos

long getTimeNanos(EventKeeper.Event event)

Get the amount of time taken by this event, in nanoseconds.

Parameters:

event - the event to get the time for

Returns:

the total time measured for this event, in nanoseconds. If the event was never recorded, return 0 instead.

getTime

default long getTime(EventKeeper.Event event,
                     java.util.concurrent.TimeUnit theUnit)

Get the amount of time taken by this event, in the specified units. Important note: If the time that was measured in nanoseconds does not evenly divide the unit that is specified (which is likely, considering time), then some precision may be lost in the conversion. Use this carefully.

Parameters:

event - the event to get the time for

theUnit - the unit to get time in

Returns:

the total time measured for this event, in the specified unit. If the event was never recorded, return 0.