MetricInstrument

All Known Subinterfaces:

CallbackMetricInstrument

All Known Implementing Classes:

DoubleCounterMetricInstrument, DoubleHistogramMetricInstrument, LongCounterMetricInstrument, LongGaugeMetricInstrument, LongHistogramMetricInstrument, PartialMetricInstrument
```
@Internal
public interface MetricInstrument
```
Represents a metric instrument. Metric instrument contains information used to describe a metric.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`java.lang.String`	`getDescription()`	Returns a description of the metric.
`int`	`getIndex()`	Returns the unique index of this metric instrument.
`java.lang.String`	`getName()`	Returns the name of the metric.
`java.util.List<java.lang.String>`	`getOptionalLabelKeys()`	Returns a list of optional label keys for this metric instrument.
`java.util.List<java.lang.String>`	`getRequiredLabelKeys()`	Returns a list of required label keys for this metric instrument.
`java.lang.String`	`getUnit()`	Returns the unit of measurement for the metric.
`boolean`	`isEnableByDefault()`	Indicates whether this metric instrument is enabled by default.

- Method Detail
  - getIndex
```
int getIndex()
```
    Returns the unique index of this metric instrument.
    
    Returns:
    
    the index of the metric instrument.
  - getName
```
java.lang.String getName()
```
    Returns the name of the metric.
    
    Returns:
    
    the name of the metric.
  - getDescription
```
java.lang.String getDescription()
```
    Returns a description of the metric.
    
    Returns:
    
    a description of the metric.
  - getUnit
```
java.lang.String getUnit()
```
    Returns the unit of measurement for the metric.
    
    Returns:
    
    the unit of measurement.
  - getRequiredLabelKeys
```
java.util.List<java.lang.String> getRequiredLabelKeys()
```
    Returns a list of required label keys for this metric instrument.
    
    Returns:
    
    a list of required label keys.
  - getOptionalLabelKeys
```
java.util.List<java.lang.String> getOptionalLabelKeys()
```
    Returns a list of optional label keys for this metric instrument.
    
    Returns:
    
    a list of optional label keys.
  - isEnableByDefault
```
boolean isEnableByDefault()
```
    Indicates whether this metric instrument is enabled by default.
    
    Returns:
    
    true if this metric instrument is enabled by default, false otherwise.