Package io.prometheus.client

Class Collector

java.lang.Object

io.prometheus.client.Collector

Direct Known Subclasses:

SimpleCollector

public abstract class Collector
extends Object

A collector for a set of metrics.

Normal users should use Gauge, Counter, Summary and Histogram.

Subclasssing Collector is for advanced uses, such as proxying metrics from another monitoring system. It is it the responsibility of subclasses to ensure they produce valid metrics.

See Also:

Exposition formats.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	Collector.Describable
static class	Collector.MetricFamilySamples	A metric, and all of its samples.
static class	Collector.Type

Field Summary

Fields

Modifier and Type	Field	Description
static double	MILLISECONDS_PER_SECOND	Number of milliseconds in a second.
static double	NANOSECONDS_PER_SECOND	Number of nanoseconds in a second.

Constructor Summary

Constructors

Constructor	Description
Collector()

Method Summary

Modifier and Type	Method	Description
protected static void	checkMetricLabelName(String name)	Throw an exception if the metric label name is invalid.
protected static void	checkMetricName(String name)	Throw an exception if the metric name is invalid.
abstract List<Collector.MetricFamilySamples>	collect()	Return all metrics of this Collector.
List<Collector.MetricFamilySamples>	collect(Predicate<String> sampleNameFilter)	Like collect(), but the result should only contain MetricFamilySamples where sampleNameFilter.test(name) is true for at least one Sample name.
static String	doubleToGoString(double d)	Convert a double to its string representation in Go.
<T extends Collector> T	register()	Register the Collector with the default registry.
<T extends Collector> T	register(CollectorRegistry registry)	Register the Collector with the given registry.
static String	sanitizeMetricName(String metricName)	Sanitize metric name

Methods inherited from class java.lang.Object

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

Field Detail

NANOSECONDS_PER_SECOND

public static final double NANOSECONDS_PER_SECOND

Number of nanoseconds in a second.

See Also:

Constant Field Values

MILLISECONDS_PER_SECOND

public static final double MILLISECONDS_PER_SECOND

Number of milliseconds in a second.

See Also:

Constant Field Values

Constructor Detail

Collector

public Collector()

Method Detail

collect

public abstract List<Collector.MetricFamilySamples> collect()

Return all metrics of this Collector.

collect

public List<Collector.MetricFamilySamples> collect(Predicate<String> sampleNameFilter)

Like collect(), but the result should only contain MetricFamilySamples where sampleNameFilter.test(name) is true for at least one Sample name.

The default implementation first collects all MetricFamilySamples and then discards the ones where sampleNameFilter.test(name) returns false for all names in Collector.MetricFamilySamples.getNames(). To improve performance, collector implementations should override this method to prevent MetricFamilySamples from being collected if they will be discarded anyways. See ThreadExports for an example.

Note that the resulting List may contain MetricFamilySamples where some Sample names return true for sampleNameFilter.test(name) but some Sample names return false. This is ok, because before we produce the output format we will call Collector.MetricFamilySamples.filter(Predicate) to strip all Samples where sampleNameFilter.test(name) returns false.

Parameters:

sampleNameFilter - may be null, indicating that all metrics should be collected.

register

public <T extends Collector> T register()

Register the Collector with the default registry.

register

public <T extends Collector> T register(CollectorRegistry registry)

Register the Collector with the given registry.

checkMetricName

protected static void checkMetricName(String name)

Throw an exception if the metric name is invalid.

sanitizeMetricName

public static String sanitizeMetricName(String metricName)

Sanitize metric name

checkMetricLabelName

protected static void checkMetricLabelName(String name)

Throw an exception if the metric label name is invalid.

doubleToGoString

public static String doubleToGoString(double d)

Convert a double to its string representation in Go.