@Override
    public void removeIngress(String uid) {
        checkArgument(!Strings.isNullOrEmpty(uid), ERR_NULL_INGRESS_UID);

        synchronized (this) {
            if (isIngressInUse(uid)) {
                final String error = String.format(MSG_INGRESS, uid, ERR_IN_USE);
                throw new IllegalStateException(error);
            }

            Ingress ingress = k8sIngressStore.removeIngress(uid);

            if (ingress != null) {
                log.info(String.format(MSG_INGRESS,
                        ingress.getMetadata().getName(), MSG_REMOVED));
            }
        }
    }
@Test(expected = IllegalArgumentException.class)
    public void testRemoveIngressWithNull() {
        target.removeIngress(null);
    }