ignore case regex

Question

How do I ignore case for my match? I am trying to match:

public static void main(String[] args) {
    Pattern pattern = Pattern.compile("(?i)^concat\\(",Pattern.MULTILINE);
    Matcher matcher = pattern.matcher("CONCAT(trade,ca)");
    System.out.println(matcher.find());
}

Possible scenarios

CONCAT( = true
concat( = true
CONCAT(test = true
concat(test = true
concat = false
CONCAT = false
TESTCONCAT( = false

Answer 1

Pattern具有标志CASE_INSENSITIVE，因此您所需要做的只是

 Pattern pattern = Pattern.compile("^concat\\(",Pattern.MULTILINE+Pattern.CASE_INSENSITIVE);