Package com.yahoo.metrics.simple

Class MetricReceiver

java.lang.Object

com.yahoo.metrics.simple.MetricReceiver

Direct Known Subclasses:

MetricReceiver.MockReceiver

public class MetricReceiver
extends Object

The reception point for measurements. This is the class users should inject in constructors for declaring instances of Counter and Gauge for the actual measurement of metrics.

Author:

Steinar Knutsen

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	MetricReceiver.MockReceiver

Field Summary

Fields

Modifier and Type	Field	Description
static MetricReceiver	nullImplementation

Constructor Summary

Constructors

Constructor	Description
MetricReceiver(com.yahoo.concurrent.ThreadLocalDirectory<Bucket,Sample> metricsCollection, AtomicReference<Bucket> currentSnapshot)

Method Summary

Modifier and Type	Method	Description
Counter	declareCounter(String name)	Declare a counter metric without setting any default position.
Counter	declareCounter(String name, Point boundDimensions)	Declare a counter metric, with default dimension values as given.
Gauge	declareGauge(String name)	Declare a gauge metric with any default position.
Gauge	declareGauge(String name, Point boundDimensions)	Declare a gauge metric, with default dimension values as given.
Gauge	declareGauge(String name, Optional<Point> boundDimensions, MetricSettings customSettings)	Declare a gauge metric, with default dimension values as given.
Bucket	getSnapshot()	Fetch the latest metric values, aggregated over all threads for the configured sample history (by default five minutes).
PointBuilder	pointBuilder()	Create a PointBuilder instance with no default settings.
void	update(Sample sample)	Update a metric.

Methods inherited from class java.lang.Object

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

Field Detail

nullImplementation

public static final MetricReceiver nullImplementation

Constructor Detail

MetricReceiver

public MetricReceiver(com.yahoo.concurrent.ThreadLocalDirectory<Bucket,Sample> metricsCollection,
                      AtomicReference<Bucket> currentSnapshot)

Method Detail

update

public void update(Sample sample)

Update a metric. This API is not intended for clients for the simplemetrics API, declare a Counter or a Gauge using declareCounter(String), declareCounter(String, Point), declareGauge(String), or declareGauge(String, Point) instead.

Parameters:

sample - a single simple containing all meta data necessary to update a metric

declareCounter

public Counter declareCounter(String name)

Declare a counter metric without setting any default position.

Parameters:

name - the name of the metric

Returns:

a thread-safe counter

declareCounter

public Counter declareCounter(String name,
                              Point boundDimensions)

Declare a counter metric, with default dimension values as given. Create the point argument by using a builder from pointBuilder().

Parameters:

name - the name of the metric

boundDimensions - dimensions which have a fixed value in the life cycle of the metric object or null

Returns:

a thread-safe counter with given default values

declareGauge

public Gauge declareGauge(String name)

Declare a gauge metric with any default position.

Parameters:

name - the name of the metric

Returns:

a thread-safe gauge instance

declareGauge

public Gauge declareGauge(String name,
                          Point boundDimensions)

Declare a gauge metric, with default dimension values as given. Create the point argument by using a builder from pointBuilder().

Parameters:

name - the name of the metric

boundDimensions - dimensions which have a fixed value in the life cycle of the metric object or null

Returns:

a thread-safe gauge metric

declareGauge

public Gauge declareGauge(String name,
                          Optional<Point> boundDimensions,
                          MetricSettings customSettings)

Declare a gauge metric, with default dimension values as given. Create the point argument by using a builder from pointBuilder(). MetricSettings instances are built using MetricSettings.Builder.

Parameters:

name - the name of the metric

boundDimensions - an optional of dimensions which have a fixed value in the life cycle of the metric object

customSettings - any optional settings

Returns:

a thread-safe gauge metric

pointBuilder

public PointBuilder pointBuilder()

Create a PointBuilder instance with no default settings. PointBuilder instances are not thread-safe.

Returns:

an "empty" point builder instance

getSnapshot

public Bucket getSnapshot()

Fetch the latest metric values, aggregated over all threads for the configured sample history (by default five minutes). The values will be less than 1 second old, and this method has only a memory barrier as side effect.

Returns:

the latest five minutes of metrics