public synchronized static MetricRegistry setDefault(String name) {
        final MetricRegistry registry = getOrCreate(name);
        return setDefault(name, registry);
    }
@Test
    public void errorsWhenDefaultAlreadySet() {
        SharedMetricRegistries.setDefault("foobah");
        exception.expect(IllegalStateException.class);
        exception.expectMessage("Default metric registry name is already set.");
        SharedMetricRegistries.setDefault("borg");
    }