com.yammer.metrics.core
Class Timer

java.lang.Object
  com.yammer.metrics.core.Timer

All Implemented Interfaces:

Metered, Metric, Sampling, Stoppable, Summarizable

public class Timer
extends Object
implements Metered, Stoppable, Sampling, Summarizable

A timer metric which aggregates timing durations and provides duration statistics, plus throughput statistics via Meter.

Method Summary

void	clear() Clears all recorded durations.
long	count() Returns the number of events which have been marked.
TimeUnit	durationUnit() Returns the timer's duration scale unit.
String	eventType() Returns the type of events the meter is measuring.
double	fifteenMinuteRate() Returns the fifteen-minute exponentially-weighted moving average rate at which events have occurred since the meter was created.
double	fiveMinuteRate() Returns the five-minute exponentially-weighted moving average rate at which events have occurred since the meter was created.
Snapshot	getSnapshot() Returns a snapshot of the values.
double	max() Returns the longest recorded duration.
double	mean() Returns the arithmetic mean of all recorded durations.
double	meanRate() Returns the mean rate at which events have occurred since the meter was created.
double	min() Returns the shortest recorded duration.
double	oneMinuteRate() Returns the one-minute exponentially-weighted moving average rate at which events have occurred since the meter was created.
<T> void	processWith(MetricProcessor<T> processor, MetricName name, T context) Allow the given MetricProcessor to process this as a metric.
TimeUnit	rateUnit() Returns the meter's rate unit.
double	stdDev() Returns the standard deviation of all recorded durations.
void	stop() Stop the instance.
double	sum() Returns the sum of all recorded durations.
TimerContext	time() Returns a timing TimerContext, which measures an elapsed time in nanoseconds.
<T> T	time(Callable<T> event) Times and records the duration of event.
void	update(long duration, TimeUnit unit) Adds a recorded duration.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

durationUnit

public TimeUnit durationUnit()

Returns the timer's duration scale unit.

Returns:

the timer's duration scale unit

rateUnit

public TimeUnit rateUnit()

Description copied from interface: Metered

Returns the meter's rate unit.

Specified by:

rateUnit in interface Metered

Returns:

the meter's rate unit

clear

public void clear()

Clears all recorded durations.

update

public void update(long duration,
                   TimeUnit unit)

Adds a recorded duration.

Parameters:

duration - the length of the duration

unit - the scale unit of duration

time

public <T> T time(Callable<T> event)
       throws Exception

Times and records the duration of event.

Type Parameters:

T - the type of the value returned by event

Parameters:

event - a Callable whose Callable.call() method implements a process whose duration should be timed

Returns:

the value returned by event

Throws:

Exception - if event throws an Exception

time

public TimerContext time()

Returns a timing TimerContext, which measures an elapsed time in nanoseconds.

Returns:

a new TimerContext

count

public long count()

Description copied from interface: Metered

Returns the number of events which have been marked.

Specified by:

count in interface Metered

Returns:

the number of events which have been marked

fifteenMinuteRate

public double fifteenMinuteRate()

Description copied from interface: Metered

Returns the fifteen-minute exponentially-weighted moving average rate at which events have occurred since the meter was created.

This rate has the same exponential decay factor as the fifteen-minute load average in the top Unix command.

Specified by:

fifteenMinuteRate in interface Metered

Returns:

the fifteen-minute exponentially-weighted moving average rate at which events have occurred since the meter was created

fiveMinuteRate

public double fiveMinuteRate()

Description copied from interface: Metered

Returns the five-minute exponentially-weighted moving average rate at which events have occurred since the meter was created.

This rate has the same exponential decay factor as the five-minute load average in the top Unix command.

Specified by:

fiveMinuteRate in interface Metered

Returns:

the five-minute exponentially-weighted moving average rate at which events have occurred since the meter was created

meanRate

public double meanRate()

Description copied from interface: Metered

Returns the mean rate at which events have occurred since the meter was created.

Specified by:

meanRate in interface Metered

Returns:

the mean rate at which events have occurred since the meter was created

oneMinuteRate

public double oneMinuteRate()

Description copied from interface: Metered

Returns the one-minute exponentially-weighted moving average rate at which events have occurred since the meter was created.

This rate has the same exponential decay factor as the one-minute load average in the top Unix command.

Specified by:

oneMinuteRate in interface Metered

Returns:

the one-minute exponentially-weighted moving average rate at which events have occurred since the meter was created

max

public double max()

Returns the longest recorded duration.

Specified by:

max in interface Summarizable

Returns:

the longest recorded duration

min

public double min()

Returns the shortest recorded duration.

Specified by:

min in interface Summarizable

Returns:

the shortest recorded duration

mean

public double mean()

Returns the arithmetic mean of all recorded durations.

Specified by:

mean in interface Summarizable

Returns:

the arithmetic mean of all recorded durations

stdDev

public double stdDev()

Returns the standard deviation of all recorded durations.

Specified by:

stdDev in interface Summarizable

Returns:

the standard deviation of all recorded durations

sum

public double sum()

Returns the sum of all recorded durations.

Specified by:

sum in interface Summarizable

Returns:

the sum of all recorded durations

getSnapshot

public Snapshot getSnapshot()

Description copied from interface: Sampling

Returns a snapshot of the values.

Specified by:

getSnapshot in interface Sampling

Returns:

a snapshot of the values

eventType

public String eventType()

Description copied from interface: Metered

Returns the type of events the meter is measuring.

Specified by:

eventType in interface Metered

Returns:

the meter's event type

stop

public void stop()

Description copied from interface: Stoppable

Stop the instance.

Specified by:

stop in interface Stoppable

processWith

public <T> void processWith(MetricProcessor<T> processor,
                            MetricName name,
                            T context)
                 throws Exception

Description copied from interface: Metric

Allow the given MetricProcessor to process this as a metric.

Specified by:

processWith in interface Metric

Type Parameters:

T - the type of the context object

Parameters:

processor - a MetricProcessor

name - the name of the current metric

context - a given context which should be passed on to processor

Throws:

Exception - if something goes wrong