@Override
    public void collectDouble(MetricDescriptor descriptor, double value) {
        for (MetricsCollector collector : collectors) {
            collector.collectDouble(descriptor, value);
        }
    }
@Test
    public void testCollectDouble() {
        compositeCollector.collectDouble(metricsDescriptor, 42.42D);

        verify(collectorMock1).collectDouble(metricsDescriptor, 42.42D);
        verify(collectorMock2).collectDouble(metricsDescriptor, 42.42D);
    }