private static Set<String> getSupportedProperties(Map<String, List<HttpPropertyRequest>> httpPropertyRequests) {
    Set<String> supportedProperties = new HashSet<>();

    for (List<HttpPropertyRequest> httpPropertyRequestList : httpPropertyRequests.values()) {
      for (HttpPropertyRequest httpPropertyRequest : httpPropertyRequestList) {
        supportedProperties.addAll(httpPropertyRequest.getSupportedProperties());
      }
    }
    return Collections.unmodifiableSet(supportedProperties);
  }
Property provider for host component resources that is used to read HTTP data from another server.
ambari-server/src/main/java/org/apache/ambari/server/controller/internal/HttpPropertyProvider.java