@Override
  public List<Instance> getInstances(String feedName) {
    Map<String, Instance> instances = instanceMap.get(feedName);
    if (instances != null) {
      return new LinkedList<>(instances.values());
    }
    return Collections.emptyList();
  }
An IvoryService implementation used for testing the DR related resource providers.
ambari-server/src/test/java/org/apache/ambari/server/controller/internal/TestIvoryService.java