How to check if a String contains another String in a case insensitive manner in Java?

Question

Say I have two strings,

String s1 = \"AbBaCca\";
String s2 = \"bac\";

I want to perform a check returning that s2 is contained

Answer 1

One problem with the answer by Dave L. is when s2 contains regex markup such as \d, etc.

You want to call Pattern.quote() on s2:

Pattern.compile(Pattern.quote(s2), Pattern.CASE_INSENSITIVE).matcher(s1).find();