public VlanId egressInnerVlan() {
        if (!object.has(EGRESS_INNER_VLAN)) {
            return VlanId.NONE;
        }

        try {
            return VlanId.vlanId(object.path(EGRESS_INNER_VLAN).asText());
        } catch (IllegalArgumentException e) {
            return null;
        }
    }
@Test
    public void egressInnerVlan() {
        VlanId egressInnerVlan = config.egressInnerVlan();
        assertNotNull("egressInnerVlan should not be null", egressInnerVlan);
        assertThat(egressInnerVlan, is(EGRESS_INNER_VLAN_1));
    }