I noticed the issuehttps://github.com/JSQLParser/JSqlParser/issues/1776 , but still can't think of a good solution

Greetings!

There is no direct way to access such SQL comments because they do not have clear position in the AST. Example:

SELECT/*comment 1*//*comment 2*/ column1from dual;

It's impossible to decide if those comments are properties of the NodesSELECT orcolumn1 and so the parsed AST can't be easily rewritten into a text.

However, there are certain work arounds:

1. your scan your statements first for comments and determine the "non-whitespace position" of each comment.
   Given, that parsing/de-parsing does not change the content of the SQL, you can insert your comment later again at this "non-whitespace" position.
   I have done exactly this for JSQLFormatter, look-up theComment-Map implementation.

2. you can access the Special AST Nodes and re-insert into the AST
   This has been done here.