private JMXHostProvider jmxHostProvider(Map<String, UriInfo> overriddenJmxUris, JMXHostProvider defaultProvider, ConfigHelper configHelper) {
    return overriddenJmxUris.isEmpty() ? defaultProvider : new ConfigBasedJmxHostProvider(overriddenJmxUris, defaultProvider, configHelper);
  }
PropertyHelper/AbstractPropertyProvider expect map of maps,
that's why we wrap metrics into map
ambari-server/src/main/java/org/apache/ambari/server/controller/internal/StackDefinedPropertyProvider.java