docs: public String qualifiedIdentifier() throws RecognitionException {
          String qi = "";
          try {
              Token first = match(input,
                      DRL6Lexer.ID,
                      null,
                      new int[]{DRL6Lexer.DOT},
                      DroolsEditorType.IDENTIFIER);
              if (state.failed)
                  return qi;
  
              Token last = first;
              while (input.LA(1) == DRL6Lexer.DOT && input.LA(2) == DRL6Lexer.ID) {
                  last = match(input,
                          DRL6Lexer.DOT,
                          null,
                          new int[]{DRL6Lexer.ID},
                          DroolsEditorType.IDENTIFIER);
                  if (state.failed)
                      return qi;
                  last = match(input,
                          DRL6Lexer.ID,
                          null,
                          new int[]{DRL6Lexer.DOT},
                          DroolsEditorType.IDENTIFIER);
                  if (state.failed)
                      return qi;
              }
              qi = input.toString(first,
                      last);
              qi = qi.replace(" ",
                      "");
          } catch (RecognitionException re) {
              reportError(re);
          }
          return qi;
      }