Java regex replaceAll multiline

Question

I have a problem with the replaceAll for a multiline string:

String regex = \"\\\\s*/\\\\*.*\\\\*/\";
String testWorks = \" /** this should be replaced **/ j         


        

Answer 1

Add Pattern.DOTALL to the compile, or (?s) to the pattern.

This would work

String regex = "(?s)\\s*/\\*.*\\*/";

See Match multiline text using regular expression

Answer 2

The meta character . matches any character other than newline. That is why your regex does not work for multi line case.

To fix this replace . with [\d\D] that matches any character including newline.

Code In Action

Answer 3

You need to use the Pattern.DOTALL flag to say that the dot should match newlines. e.g.

Pattern.compile(regex, Pattern.DOTALL).matcher(testIllegal).replaceAll("x")

or alternatively specify the flag in the pattern using (?s) e.g.

String regex = "(?s)\\s*/\\*.*\\*/";