How to find if a Java String contains X or Y and contains Z

Question

I\'m pretty sure regular expressions are the way to go, but my head hurts whenever I try to work out the specific regular expression.

What regular expression do I ne

Answer 1

I think this regexp will do the trick (but there must be a better way to do it):

(.*(ERROR|WARNING).*parsing)|(.*parsing.*(ERROR|WARNING))

Answer 2

If you really want to use regular expressions, you can use the positive lookahead operator:

(?i)(?=.*?(?:ERROR|WARNING))(?=.*?parsing).*

Examples:

Pattern p = Pattern.compile("(?=.*?(?:ERROR|WARNING))(?=.*?parsing).*", Pattern.CASE_INSENSITIVE); // you can also use (?i) at the beginning
System.out.println(p.matcher("WARNING at line X doing parsing of Y").matches()); // true
System.out.println(p.matcher("An error at line X doing parsing of Y").matches()); // true
System.out.println(p.matcher("ERROR Hello parsing world").matches()); // true       
System.out.println(p.matcher("A problem at line X doing parsing of Y").matches()); // false