org.apache.cassandra.metrics

Class Sampler<T>

java.lang.Object

org.apache.cassandra.metrics.Sampler<T>

Direct Known Subclasses:

FrequencySampler, MaxSampler

public abstract class Sampler<T>
extends java.lang.Object

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Sampler.Sample<S> Represents the ranked items collected during a sample period
static class	Sampler.SamplerType

Field Summary

Fields

Modifier and Type	Field and Description
static java.util.concurrent.ThreadPoolExecutor	samplerExecutor

Constructor Summary

Constructors

Constructor and Description
Sampler()

Method Summary

Modifier and Type	Method and Description
void	addSample(T item, int value)
abstract void	beginSampling(int capacity, int durationMillis)
abstract java.util.List<Sampler.Sample<T>>	finishSampling(int count)
protected abstract void	insert(T item, long value)
abstract boolean	isEnabled()
abstract java.lang.String	toString(T value)

Methods inherited from class java.lang.Object

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

Field Detail

samplerExecutor

public static final java.util.concurrent.ThreadPoolExecutor samplerExecutor

Constructor Detail

Sampler

public Sampler()

Method Detail

addSample

public void addSample(T item,
                      int value)

insert

protected abstract void insert(T item,
                               long value)

isEnabled

public abstract boolean isEnabled()

beginSampling

public abstract void beginSampling(int capacity,
                                   int durationMillis)

finishSampling

public abstract java.util.List<Sampler.Sample<T>> finishSampling(int count)

toString

public abstract java.lang.String toString(T value)