private StackServiceRequest getRequest(Map<String, Object> properties) {
    return new StackServiceRequest(
        (String) properties.get(STACK_NAME_PROPERTY_ID),
        (String) properties.get(STACK_VERSION_PROPERTY_ID),
        (String) properties.get(SERVICE_NAME_PROPERTY_ID),
        (String) properties.get(CREDENTIAL_STORE_SUPPORTED),
        (String) properties.get(CREDENTIAL_STORE_ENABLED));
  }
KerberosServiceDescriptorFactory used to create KerberosServiceDescriptor instances
ambari-server/src/main/java/org/apache/ambari/server/controller/internal/StackServiceResourceProvider.java