code: public static String getGrouperGroupAttribute(final GrouperGroupField groupField, final WsGroup group) {
          switch (groupField) {
              case DISPLAY_EXTENSION:
                  return group.getDisplayExtension();
              case DISPLAY_NAME:
                  return group.getDisplayName();
              case EXTENSION:
                  return group.getExtension();
              case NAME:
              default:
                  return group.getName();
          }
      }
docs: Construct grouper group attribute.
  This is the name of every individual group attribute
  transformed into a CAS attribute value.
  
  @param groupField the group field
  @param group      the group
  @return the final attribute name