gistfile1.md

Adding Custom Metric subtype

To implement a new metric subtype, implement ExtensionMetric marker interface and put @MetricExtension on it

@NamedMetric("dac.mansion.foo.bar") @Singleton
public class MyGauge extends Gauge<Integer> implements ExtensionMetric {
     @Override
     public Integer getValue() {
         return queue.size();
     }
 }

To define metrics that does not need any custom subtypes, define an extension module and list metrics:

@Extension
public class MyModule extends MetricModule {
    protected void configure() {
        counter("dac.mansion.foo");
        counter("dac.mansion.bar");
        histogram("dac.mansion.zot");
    }
}

In either case, you can then inject them where you need them:

@Inject @NamedMetric("dac.mansion.foo")
Counter foo;

@Inject @NamedMetric("dac.mansion.foo.bar")
MyGauge my;

You can also inject MetricRegistry and do whatever you want to do with it.