@Test
public void testAsCanonicalStringDomainData() {

    Mockito.when(mockDomain.getAuditEnabled()).thenReturn(null);
    Mockito.when(mockDomain.getEnabled()).thenReturn(null);
    Mockito.when(mockDomain.getRoles()).thenReturn(null);
    Mockito.when(mockDomain.getGroups()).thenReturn(null);
    Mockito.when(mockDomain.getServices()).thenReturn(null);
    Mockito.when(mockDomain.getMemberExpiryDays()).thenReturn(null);
    Mockito.when(mockDomain.getServiceExpiryDays()).thenReturn(null);
    Mockito.when(mockDomain.getTokenExpiryMins()).thenReturn(null);
    String check = SignUtils.asCanonicalString(mockDomain);
    assertNotNull(check);
    assertEquals(check,"{\"roleCertExpiryMins\":0,\"roles\":[],\"serviceCertExpiryMins\":0,\"services\":[],\"ypmId\":0}");
}