Interface Gauge<N extends Number>

Type Parameters:

N - subtype of Number which a specific gauge reports

All Superinterfaces:

Meter, Wrapper, Wrapper

public interface Gauge<N extends Number>
extends Meter

Exposes as a meter a value that can increase or decrease and is updated by external logic, not by explicit invocations of methods on this type.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static interface	Gauge.Builder<N extends Number>	Builder for a new gauge.

Nested classes/interfaces inherited from interface Meter

Meter.BaseUnits, Meter.Id, Meter.Scope, Meter.Type

Modifier and Type	Interface	Description
static class	Meter.BaseUnits	Common unit declarations (inspired by the list from MicroProfile metrics).
static interface	Meter.Id	Unique idenfier for a meter.
static class	Meter.Scope	Deprecated, for removal: This API element is subject to removal in a future version. Core metrics ignores scope values, and this type will be removed.
static enum	Meter.Type	Type of meter.

Method Summary

Modifier and Type	Method	Description
static <N extends Number> Gauge.Builder<N>	builder(String name, Supplier<N> numberSupplier)	Deprecated, for removal: This API element is subject to removal in a future version. this method uses service registry to get a MetricsFactory instance, which may be inefficient, use MetricsFactory.gaugeBuilder(String, java.util.function.Supplier) instead
static <T> Gauge.Builder<Double>	builder(String name, T stateObject, ToDoubleFunction<T> fn)	Deprecated, for removal: This API element is subject to removal in a future version. this method uses service registry to get a MetricsFactory instance, which may be inefficient, use MetricsFactory.gaugeBuilder(String, Object, java.util.function.ToDoubleFunction) instead
N	value()	Returns the value of the gauge.

Methods inherited from interface Meter

baseUnit, description, id, scope, type

Modifier and Type	Method	Description
Optional<String>	baseUnit()	Returns the meter's base unit.
Optional<String>	description()	Returns the meter's description.
Meter.Id	id()	Returns the meter ID.
default Optional<String>	scope()	Deprecated, for removal: This API element is subject to removal in a future version. Core metrics does not assign scopes, and this method will be removed.
Meter.Type	type()	Returns the meter type.

Methods inherited from interface Wrapper

unwrap

Modifier and Type	Method	Description
<T> T	unwrap(Class<? extends T> type)	Unwraps the delegate as the specified type.

Method Details

builder

@Deprecated(forRemoval=true,
            since="27.0.0")
static <T> Gauge.Builder<Double> builder(String name,
 T stateObject,
 ToDoubleFunction<T> fn)

Deprecated, for removal: This API element is subject to removal in a future version.

this method uses service registry to get a MetricsFactory instance, which may be inefficient, use MetricsFactory.gaugeBuilder(String, Object, java.util.function.ToDoubleFunction) instead

Creates a builder for creating a new gauge based on applying a function to a state object.

Type Parameters:

T - type of the state object

Parameters:

name - gauge name

stateObject - state object which maintains the gauge value

fn - function which, when applied to the state object, returns the gauge value

Returns:

new builder

builder

@Deprecated(forRemoval=true,
            since="27.0.0")
static <N extends Number> Gauge.Builder<N> builder(String name,
 Supplier<N> numberSupplier)

Deprecated, for removal: This API element is subject to removal in a future version.

this method uses service registry to get a MetricsFactory instance, which may be inefficient, use MetricsFactory.gaugeBuilder(String, java.util.function.Supplier) instead

Creates a builder for a supplier-based gauge.

Type Parameters:

N - subtype of Number which the supplier provides

Parameters:

name - gauge name

numberSupplier - Supplier for an instance of a type which extends Number

Returns:

new builder

value

N value()

Returns the value of the gauge.

Invoking this method triggers the sampling of the value or invocation of the function provided when the gauge was registered.

Returns:

current value of the gauge