code: public String mapSafely(String attributeKey, XAttributeNameMap mapping) {
  		String alias = null;
  		if(mapping != null) {
  			// check valid requested mapping
  			alias = mapping.map(attributeKey);
  		}
  		if(alias == null) {
  			// no match in requested mapping, try standard mapping
  			alias = standardMapping.map(attributeKey);
  		}
  		if(alias == null) {
  			// no match in standard mapping, fall back to key
  			alias = attributeKey;
  		}
  		return alias;
  	}
docs: Maps an attribute safely, using the given attribute mapping.
  Safe mapping attempts to map the attribute using the given
  mapping first. If this does not succeed, the standard mapping
  (EN) will be used for mapping. If no mapping is available in
  the standard mapping, the original attribute key is returned
  unchanged. This way, it is always ensured that this method
  returns a valid string for naming attributes.
  
  @param attributeKey Key of the attribute to map.
  @param mapping Mapping to be used preferably.
  @return The safe mapping for the given attribute key.