private boolean removeConfigurationSpecifications(AbstractKerberosDescriptorContainer kerberosDescriptorContainer, Map<String, Collection<String>> configurations) {
    boolean updated = false;
    if (kerberosDescriptorContainer != null) {
      if (!MapUtils.isEmpty(configurations)) {
        for (Map.Entry<String, Collection<String>> entry : configurations.entrySet()) {
          String configType = entry.getKey();

          for (String propertyName : entry.getValue()) {
            Map<String, KerberosConfigurationDescriptor> configurationDescriptors = kerberosDescriptorContainer.getConfigurations(false);
            KerberosConfigurationDescriptor configurationDescriptor = (configurationDescriptors == null)
                ? null
                : configurationDescriptors.get(configType);
            if (configurationDescriptor != null) {
              Map<String, String> properties = configurationDescriptor.getProperties();
              if ((properties != null) && properties.containsKey(propertyName)) {
                properties.remove(propertyName);
                LOG.info("Removed {}/{} from the descriptor named {}", configType, propertyName, kerberosDescriptorContainer.getName());
                updated = true;

                // If there are no more properties in the configurationDescriptor, remove it from the container.
                if (properties.isEmpty()) {
                  configurationDescriptors.remove(configType);
                  kerberosDescriptorContainer.setConfigurations(configurationDescriptors);
                }
              }
            }
          }
        }
      }
    }

    return updated;
  }
Given an {@link AbstractKerberosDescriptorContainer}, attempts to remove the specified
configurations (<code>configType/propertyName</code> from it.

@param kerberosDescriptorContainer the container to update
@param configurations              a map of configuration types to sets of property names.
@return true if changes where made to the container; false otherwise
ambari-server/src/main/java/org/apache/ambari/server/upgrade/UpgradeCatalog252.java