code: public Set<String> getNewElementKeys() {
  
          Set<String> result = new HashSet<String>();
          for (CmsContainerConfiguration configuration : m_parentConfigurations) {
              result.addAll(configuration.getNewElements().keySet());
          }
          return result;
      }
docs: Gets the keys of new elements.<p>
  
  @return a set containing the keys of the new elements