code: public Set<String> getCachedVariations(String key, CmsObject cms) {
  
          if (!isEnabled() || !OpenCms.getRoleManager().hasRole(cms, CmsRole.WORKPLACE_MANAGER)) {
              return null;
          }
          Object o = m_keyCache.get(key);
          if (o != null) {
              return synchronizedCopyKeys(((CmsFlexCacheVariation)o).m_map);
          }
          return null;
      }
docs: Returns all variations in the cache for a given resource name.
  The variations are of type String.<p>
  
  Useful if you want to show a list of all cached entry - variations,
  like on the FlexCache administration page.<p>
  
  Only users with administrator permissions are allowed
  to perform this operation.<p>
  
  @param key the resource name for which to look up the variations for
  @param cms the CmsObject used for user authorization
  @return a Set of cached variations (which are of type String)