    @Test
    public void testSomeCached() {

        Assert.assertEquals(MetricId.EMPTY.tagged("endpoint", "foo"), endpointCache.get("foo"));
        Assert.assertEquals(MetricId.EMPTY.tagged("endpoint", "foo"), endpointCache.get("foo"));
        Assert.assertEquals(1, callCount.get());

        Assert.assertEquals(MetricId.EMPTY.tagged("endpoint", "bar"), endpointCache.get("bar"));
        Assert.assertEquals(2, callCount.get());
    }