@Override
    public boolean userDefinedIndexMode(boolean enable) {
        if (meters.isEmpty() && meterIdGenerators.isEmpty()) {
            userDefinedIndexMode = enable;
        } else {
            log.warn("Unable to {} user defined index mode as store did" +
                    "already some allocations", enable ? "activate" : "deactivate");
        }
        return userDefinedIndexMode;
    }
@Test
    public void testDisableUserDefinedIndex() {
        initMeterStore(true);

        assertFalse(meterStore.userDefinedIndexMode(false));
    }