@Test
public void scopesMetricsBeforeDelegatingToUnderlyingMetricRegistry() {
    MetricRegistry metricRegistry = mock(MetricRegistry.class);
    MetricRegistry scopedMetricRegistry = new ScopedMetricRegistry("scope", metricRegistry);

    scopedMetricRegistry.counter("counter");
    verify(metricRegistry).counter("scope.counter");

    scopedMetricRegistry.meter("meter");
    verify(metricRegistry).meter("scope.meter");

    scopedMetricRegistry.histogram("histogram");
    verify(metricRegistry).histogram("scope.histogram");

    scopedMetricRegistry.timer("timer");
    verify(metricRegistry).timer("scope.timer");

    Metric metric = new Counter();
    scopedMetricRegistry.register("register.counter", metric);
    verify(metricRegistry).register("scope.register.counter", metric);

    scopedMetricRegistry.deregister("register.counter");
    verify(metricRegistry).deregister("scope.register.counter");

    MetricRegistryListener listener = mock(MetricRegistryListener.class);

    scopedMetricRegistry.addListener(listener);
    verify(metricRegistry).addListener(listener);

    scopedMetricRegistry.removeListener(listener);
    verify(metricRegistry).removeListener(listener);
}
 

@Override
public void addListener(MetricRegistryListener listener) {
}
 

@Override
public void removeListener(MetricRegistryListener listener) {
}
 

@Override
public void addListener(MetricRegistryListener listener) {
    this.metricRegistry.addListener(listener);
}
 

@Override
public void removeListener(MetricRegistryListener listener) {
    this.metricRegistry.removeListener(listener);
}
 

@Override
public void addListener(MetricRegistryListener listener) {
    this.parent.addListener(listener);
}
 

@Override
public void removeListener(MetricRegistryListener listener) {
    this.parent.removeListener(listener);
}
 

@BeforeEach
public void setUp() {
    this.metricRegistry = new CodaHaleMetricRegistry(new com.codahale.metrics.MetricRegistry());
    this.listener = mock(MetricRegistryListener.class);
}
 

/**
 * Adds a {@link MetricRegistryListener} to a collection of listeners that will be notified on
 * metric creation.  Listeners will be notified in the order in which they are added.
 * <p/>
 * <b>N.B.:</b> The listener will be notified of all existing metrics when it first registers.
 *
 * @param listener the listener that will be notified
 */
void addListener(MetricRegistryListener listener);
 

/**
 * Removes a {@link MetricRegistryListener} from this registry's collection of listeners.
 *
 * @param listener the listener that will be removed
 */
void removeListener(MetricRegistryListener listener);