Search for non-printable characters (Carriage Return, Tab, etc.) in code editor of IntelliJ?

Question

In the code editor of IntelliJ 2018, using either menu item:

• Edit > Find > Find…
• Edit > Find > Replace…

…how can I find invisible (non-printing) characters?

I am referring to characters such as:

• CARRIAGE RETURN
• LINE FEED
• INFORMATION SEPARATOR ONE

Answer 1

Enabling "Regex" checkbox, you can use the full regex syntax. I was able to search for spaces with \u0020 and for LF with \x0a.

• Carriage return and line feed match \r and \n respectively.
• Arbitrary Unicode character syntax: \uFFFF, where FFFF is a hex Unicode character code.
• Arbitrary ASCII character syntax: \xFF, where FF is an ASCII hex code.