code: private RepositoryQuotaManager getRepositoryQuotaManager(String repositoryName) throws IllegalStateException
     {
        RepositoryQuotaManager rqm = rQuotaManagers.get(repositoryName);
        if (rqm == null)
        {
           throw new IllegalStateException("Repository " + repositoryName + " is not registered");
        }
  
        return rqm;
     }
docs: Returns registered {@link RepositoryQuotaManager} or throws exception.