@Override
  public Set<ClusterResponse> getClusters(Set<ClusterRequest> requests) throws AmbariException, AuthorizationException {
    Set<ClusterResponse> response = new HashSet<>();
    for (ClusterRequest request : requests) {
      try {
        response.addAll(getClusters(request));
      } catch (ClusterNotFoundException e) {
        if (requests.size() == 1) {
          // only throw exception if 1 request.
          // there will be > 1 request in case of OR predicate
          throw e;
        }
      }
    }
    return response;
  }
Get a request response for the given request ids.  Note that this method
fully populates a request resource including the set of task sub-resources
in the request response.
ambari-server/src/main/java/org/apache/ambari/server/controller/AmbariManagementControllerImpl.java