@Override
    public long read() {
        return gaugeSource.read();
    }
@Test
    public void whenDoubleProbeField() {
        SomeObject someObject = new SomeObject();
        metricsRegistry.registerStaticMetrics(someObject, "foo");

        LongGauge gauge = metricsRegistry.newLongGauge("foo.doubleField");
        assertEquals(round(someObject.doubleField), gauge.read());
    }