@Override
    public LongGaugeImpl newLongGauge(String name) {
        checkNotNull(name, "name can't be null");

        LongGaugeImpl gauge = new LongGaugeImpl(this, name);
        gauges.put(createDescriptor(name).lookupView(), gauge);
        return gauge;
    }
@Test(expected = NullPointerException.class)
    public void newGauge_whenNullName() {
        metricsRegistry.newLongGauge(null);
    }