code: public void assignID(XAttributable element, XID id) {
  		if (id != null) {
  			XAttributeID attr = (XAttributeID) ATTR_ID.clone();
  			attr.setValue(id);
  			element.getAttributes().put(KEY_ID, attr);
  		}
  	}
docs: Assigns any log data hierarchy element its id, as defined by this
  extension's id attribute.
  
  @param element
  Log hierarchy element to assign id to.
  @param id
  The id to be assigned.