Package org.xbib.metrics.common

Class Sampler

java.lang.Object

org.xbib.metrics.common.Sampler

All Implemented Interfaces:

org.xbib.metrics.api.Metered, org.xbib.metrics.api.Metric, org.xbib.metrics.api.Sampling

public class Sampler
extends java.lang.Object
implements org.xbib.metrics.api.Metered, org.xbib.metrics.api.Sampling

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

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Sampler.Context	A timing context.

Constructor Summary

Constructors

Constructor	Description
Sampler(java.util.concurrent.ScheduledExecutorService executorService)	Creates a new Sampler using an ExponentiallyDecayingReservoir and the default Clock.
Sampler(org.xbib.metrics.api.Reservoir reservoir, java.util.concurrent.ScheduledExecutorService executorService)	Creates a new Sampler that uses the given Reservoir.
Sampler(org.xbib.metrics.api.Reservoir reservoir, org.xbib.metrics.api.Clock clock, java.util.concurrent.ScheduledExecutorService executorService)	Creates a new Sampler that uses the given Reservoir and Clock.

Method Summary

Modifier and Type	Method	Description
long	getCount()
double	getFifteenMinuteRate()
double	getFiveMinuteRate()
double	getMeanRate()
double	getOneMinuteRate()
org.xbib.metrics.api.Snapshot	getSnapshot()
Sampler.Context	time()	Returns a new Sampler.Context.
void	time(java.lang.Runnable event)	Times and records the duration of an event.
<T> T	time(java.util.concurrent.Callable<T> event)	Records the duration of event.
void	update(long duration, java.util.concurrent.TimeUnit unit)	Adds a recorded duration.

Methods inherited from class java.lang.Object

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

Constructor Detail

Sampler

public Sampler(java.util.concurrent.ScheduledExecutorService executorService)

Creates a new Sampler using an ExponentiallyDecayingReservoir and the default Clock.

Parameters:

executorService - the executor service

Sampler

public Sampler(org.xbib.metrics.api.Reservoir reservoir,
               java.util.concurrent.ScheduledExecutorService executorService)

Creates a new Sampler that uses the given Reservoir.

Parameters:

reservoir - the Reservoir implementation the sampler should use

executorService - the executor service

Sampler

public Sampler(org.xbib.metrics.api.Reservoir reservoir,
               org.xbib.metrics.api.Clock clock,
               java.util.concurrent.ScheduledExecutorService executorService)

Creates a new Sampler that uses the given Reservoir and Clock.

Parameters:

reservoir - the Reservoir implementation the sampler should use

clock - the Clock implementation the sampler should use

executorService - the executor service

Method Detail

update

public void update(long duration,
                   java.util.concurrent.TimeUnit unit)

Adds a recorded duration.

Parameters:

duration - the length of the duration

unit - the scale unit of duration

time

public <T> T time(java.util.concurrent.Callable<T> event)
           throws java.lang.Exception

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:

java.lang.Exception - if event throws an Exception

time

public void time(java.lang.Runnable event)

Times and records the duration of an event.

Parameters:

event - a Runnable whose Runnable.run() method implements a process whose duration should be timed

time

public Sampler.Context time()

Returns a new Sampler.Context.

Returns:

a new Sampler.Context

See Also:

Sampler.Context

getCount

public long getCount()

Specified by:

getCount in interface org.xbib.metrics.api.Metered

getFifteenMinuteRate

public double getFifteenMinuteRate()

Specified by:

getFifteenMinuteRate in interface org.xbib.metrics.api.Metered

getFiveMinuteRate

public double getFiveMinuteRate()

Specified by:

getFiveMinuteRate in interface org.xbib.metrics.api.Metered

getMeanRate

public double getMeanRate()

Specified by:

getMeanRate in interface org.xbib.metrics.api.Metered

getOneMinuteRate

public double getOneMinuteRate()

Specified by:

getOneMinuteRate in interface org.xbib.metrics.api.Metered

getSnapshot

public org.xbib.metrics.api.Snapshot getSnapshot()

Specified by:

getSnapshot in interface org.xbib.metrics.api.Sampling