Java regex text replace

Question

I have text like this

Some. / text to-match (1)

I wanna replace ./() for _ has next

Some_text_to_match_1

How do it the pattern?

Answer 1

You may trim the string from non-word chars on both ends (with .replaceAll("^\\\\W+|\\\\W+$", "") ), and then replace 1 or more non-word character chunks with _ inside the string (with .replaceAll("\\\\W+", "_") ):

String s = "Some. / text to-match (1)";
s = s.replaceAll("^\\W+|\\W+$", "").replaceAll("\\W+", "_");
System.out.println(s);

See the Java demo

Details :

• \\W matches a non-word character
• + matches 1 or more occurrences of the subpattern this quantifier modifies.

Since we need to use 2 different replacements when trimming the string and then replacing non-word chars inside it, we cannot use just 1 replaceAll .