Java - Regex - Remove comments

Question

I want to remove comments in Java code. I have seen a lot of examples, but each was written wrong.

Here is example of code:

String somestring = \"htt         


        

Answer 1

Already commented this but lets see how far we get. Java doesn't do regex literals so stripping that one from this answer we get the following regex:

((['"])(?:(?!\2|\\).|\\.)*\2)|\/\/[^\n]*|\/\*(?:[^*]|\*(?!\/))*\*\/

Debuggex Demo

If we then "replace" every match with the first capture group, every match that doesn't have a capture group to begin with (i.e. a comment) is removed:

Regex101 substitution Demo

A explanation of the more generic "match this except in conditions a|b|c"-technique I employed is available here.