org.apache.sling.commons.metrics

Interface Gauge<T>

Type Parameters:

T - the type of the metric's value

public interface Gauge<T>

A gauge metric is an instantaneous reading of a particular value. To instrument a queue's depth, for example:

 final Queue<String> queue = new ConcurrentLinkedQueue<String>();
 final Gauge<Integer> queueDepth = new Gauge<Integer>() {
     public Integer getValue() {
         return queue.size();
     }
 };
 

A Gauge instance should be registered with OSGi ServiceRegistry with Gauge#NAME set to Gauge name. Then the Gauge instance would be registered with MetricService via whiteboard pattern

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	NAME Service property name which determines the name of the Gauge

Method Summary

Modifier and Type	Method and Description
T	getValue() Returns the metric's current value.

Field Detail

NAME

static final java.lang.String NAME

Service property name which determines the name of the Gauge

See Also:

Constant Field Values

Method Detail

getValue

T getValue()

Returns the metric's current value.

Returns:

the metric's current value