Interface FunctionCounter

All Superinterfaces:

Meter

All Known Implementing Classes:

CompositeFunctionCounter, CumulativeFunctionCounter, DropwizardFunctionCounter, NoopFunctionCounter, StepFunctionCounter

public interface FunctionCounter
extends Meter

A counter that tracks a monotonically increasing function.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static class	FunctionCounter.Builder<T>	Fluent builder for function counters.
static final class	FunctionCounter.TimeBasedBuilder<T>	Fluent builder for function counters that count monotonically increasing time.

Nested classes/interfaces inherited from interface Meter

Meter.Id, Meter.MeterProvider<T>, Meter.Type

Method Summary

Modifier and Type	Method	Description
static <T> FunctionCounter.Builder<T>	builder(String name, T obj, ToDoubleFunction<T> f)	Build a function-tracking counter that produces a monotonically increasing count from the state object.
static <T> FunctionCounter.TimeBasedBuilder<T>	builder(String name, T obj, ToDoubleFunction<T> objToCountFunction, TimeUnit sourceUnit)	Build a function-tracking counter for a function that tracks monotonically increasing time.
double	count()
default Iterable<Measurement>	measure()	Get a set of measurements.

Methods inherited from interface Meter

close, getId, match, use

Method Details

builder

static <T> FunctionCounter.Builder<T> builder(String name,
 T obj,
 ToDoubleFunction<T> f)

Build a function-tracking counter that produces a monotonically increasing count from the state object.

Type Parameters:

T - The type of the state object.

Parameters:

name - The counter's name.

obj - State object used to compute a count.

f - Function that produces a monotonically increasing count from the state object.

Returns:

A new function counter builder.

builder

static <T> FunctionCounter.TimeBasedBuilder<T> builder(String name,
 T obj,
 ToDoubleFunction<T> objToCountFunction,
 TimeUnit sourceUnit)

Build a function-tracking counter for a function that tracks monotonically increasing time. The time value will automatically scale to the base time unit expected by each registry implementation.

Type Parameters:

T - The type of the state object.

Parameters:

name - The counter's name.

obj - State object used to compute a value.

objToCountFunction - Function that produces a monotonically increasing time count from the state object.

sourceUnit - Time unit of the value returned by the count function.

Returns:

A new time-based function counter builder.

Since:

1.18.0

count

double count()

Returns:

The cumulative count since this counter was created.

measure

default 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.