Package org.apache.hadoop.metrics2.annotation

Annotation Type Metric

@Public
@Evolving
@Documented
@Target({FIELD,METHOD})
@Retention(RUNTIME)
public @interface Metric

Annotation interface for a single metric used to annotate a field or a method in the class.

Optional Element Summary

Optional Elements

Modifier and Type	Optional Element	Description
java.lang.String	about
boolean	always
int	interval
java.lang.String	sampleName
Metric.Type	type
java.lang.String[]	value	Shorthand for optional name and description
java.lang.String	valueName

Element Detail

value

java.lang.String[] value

Shorthand for optional name and description

Returns:

{description} or {name, description}

Default:

{}

about

java.lang.String about

Returns:

optional description of the metric

Default:

""

sampleName

java.lang.String sampleName

Returns:

optional sample name for MutableStat/Rate/Rates

Default:

"Ops"

valueName

java.lang.String valueName

Returns:

optional value name for MutableStat/Rate/Rates

Default:

"Time"

always

boolean always

Returns:

true to create a metric snapshot even if unchanged.

Default:

false

type

Metric.Type type

Returns:

optional type (counter|gauge) of the metric

Default:

org.apache.hadoop.metrics2.annotation.Metric.Type.DEFAULT

interval

int interval

Returns:

optional roll over interval in secs for MutableQuantiles

Default:

10