http://metrics.dropwizard.io/metrics-core: Metrics is a Java library which gives you unparalleled insight into what your code does in production. Metrics provides a powerful toolkit of ways to measure the behavior of critical components in your production environment.
  • Coda Hale
  • Ryan Tenney
  • Artem Prigoda 
package com.codahale.metrics;

import java.io.Closeable;

/*
 * A tag interface to indicate that a class is a Reporter.
 */
public interface Reporter extends Closeable {

}