Package io.micrometer.core.instrument

Interface Gauge

All Superinterfaces:

Meter

All Known Subinterfaces:

TimeGauge

All Known Implementing Classes:

DefaultGauge, DropwizardGauge, NoopGauge, NoopTimeGauge

public interface Gauge
extends Meter

A gauge tracks a value that may go up or down. The value that is published for gauges is an instantaneous sample of the gauge at publishing time.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static class	Gauge.Builder<T>	Fluent builder for gauges.

Nested classes/interfaces inherited from interface io.micrometer.core.instrument.Meter

Meter.Id, Meter.Type

Method Summary

Modifier and Type	Method	Description
static Gauge.Builder<java.util.function.Supplier<java.lang.Number>>	builder(java.lang.String name, java.util.function.Supplier<java.lang.Number> f)	A convenience method for building a gauge from a supplying function, holding a strong reference to this function.
static <T> Gauge.Builder<T>	builder(java.lang.String name, T obj, java.util.function.ToDoubleFunction<T> f)
default java.lang.Iterable<Measurement>	measure()	Get a set of measurements.
double	value()	The act of observing the value by calling this method triggers sampling of the underlying number or user-defined function that defines the value for the gauge.

Methods inherited from interface io.micrometer.core.instrument.Meter

close, getId, match, use

Method Detail

builder

static <T> Gauge.Builder<T> builder(java.lang.String name,
                                    @Nullable
                                    T obj,
                                    java.util.function.ToDoubleFunction<T> f)

Type Parameters:

T - The type of object to gauge.

Parameters:

name - The gauge's name.

obj - An object with some state or function which the gauge's instantaneous value is determined from.

f - A function that yields a double value for the gauge, based on the state of obj.

Returns:

A new gauge builder.

builder

@Incubating(since="1.1.0")
static Gauge.Builder<java.util.function.Supplier<java.lang.Number>> builder(java.lang.String name,
                                                                            java.util.function.Supplier<java.lang.Number> f)

A convenience method for building a gauge from a supplying function, holding a strong reference to this function.

Parameters:

name - The gauge's name.

f - A function that yields a double value for the gauge.

Returns:

A new gauge builder.

Since:

1.1.0

value

double value()

The act of observing the value by calling this method triggers sampling of the underlying number or user-defined function that defines the value for the gauge.

Returns:

The current value.

measure

default java.lang.Iterable<Measurement> measure()

Description copied from interface: Meter

Get a set of measurements. Should always return the same number of measurements and in the same order, regardless of the level of activity or the lack thereof.

Specified by:

measure in interface Meter

Returns:

The set of measurements that represents the instantaneous value of this meter.