question: private void verifyDomainsIsNotInUse ( StringSet domains ) { checkForActiveTenantsUsingDomains ( domains ) ; checkForVdcRolesUsingDomains ( domains ) ; checkForTenantRolesUsingDomains ( domains ) ; checkForUserGroupsUsingDomains ( domains ) ; }
target:  check if given domains are in use or not, if any of them is in use, throw exception.