Package io.opentelemetry.api.metrics

Interface Meter

@ThreadSafe
public interface Meter

Provides instruments used to produce metrics.

Instruments are obtained through builders provided by this interface. Each builder has a default "type" associated with recordings that may be changed.

A Meter is generally associated with an instrumentation scope, e.g. "I monitor apache httpclient".

Choosing an instrument can be hard, but here's a rule of thumb for selecting the right instrument:

• I want to count something.
  • The value is always increasing / I want to track its rate.
    Use counterBuilder(String)
  • The value is not always increasing.
    Use upDownCounterBuilder(String)
• I want to time something, or record measurements where the statistics are important (e.g. latency).
  Use histogramBuilder(String)
• I want to measure something by sampling a value stored elsewhere.
  Use gaugeBuilder(String)

Method Summary

Modifier and Type	Method	Description
LongCounterBuilder	counterBuilder(String name)	Constructs a counter instrument.
DoubleGaugeBuilder	gaugeBuilder(String name)	Constructs an asynchronous gauge.
DoubleHistogramBuilder	histogramBuilder(String name)	Constructs a Histogram instrument.
LongUpDownCounterBuilder	upDownCounterBuilder(String name)	Constructs an up-down-counter instrument.

Method Details

counterBuilder

LongCounterBuilder counterBuilder(String name)

Constructs a counter instrument.

This is used to build both synchronous (in-context) instruments and asynchronous (callback) instruments.

Parameters:

name - the name used for the counter.

Returns:

a builder for configuring a new Counter instrument. Defaults to recording long values, but may be changed.

upDownCounterBuilder

LongUpDownCounterBuilder upDownCounterBuilder(String name)

Constructs an up-down-counter instrument.

This is used to build both synchronous (in-context) instruments and asynchronous (callback) instruments.

Parameters:

name - the name used for the counter.

Returns:

a builder for configuring a new Counter synchronous instrument. Defaults to recording long values, but may be changed.

histogramBuilder

DoubleHistogramBuilder histogramBuilder(String name)

Constructs a Histogram instrument.

Parameters:

name - the name used for the counter.

Returns:

a builder for configuring a new Histogram synchronous instrument. Defaults to recording double values, but may be changed.

gaugeBuilder

DoubleGaugeBuilder gaugeBuilder(String name)

Constructs an asynchronous gauge.

Returns:

a builder used for configuring how to report gauge measurements on demand.