@Override
  public PsiJavaToken getTokenBeforeOperand(@NotNull PsiExpression operand) {
    PsiElement element = operand;
    while(element != null) {
      if (getChildRole(element.getNode()) == ChildRole.OPERATION_SIGN) return (PsiJavaToken)element;
      element = element.getPrevSibling();
    }
    return null;
  }
@Override
  public PsiJavaToken getTokenBeforeOperand(@NotNull PsiExpression operand)