Java regex issue to get data in the brackets

Question

I want to get the data from String "Max(percentage(%))" or "Max(percentage)", what i need to get is "percentage(%)" or "percentage" in the brackets. I want to use one regex achieve the goal. Can someone help me? Below is my code:

String str = "Max(percentage)";
Pattern pattern = Pattern.compile("(?<=\\()(.+?)(?=\\))");

String str = "Max(percentage(%))";
Pattern pattern = Pattern.compile("(?<=\\()(.+?)(?<=\\))");

where's the `Matcher` part that actually tries matching it against a certain string? — Shark, Feb 13 '18 at 13:14
See Existing Answer: https://stackoverflow.com/questions/24256478/pattern-to-extract-text-between-parenthesis — Alan Blyth, Feb 13 '18 at 13:17

score -1 · Answer 1 · answered Feb 13 '18 at 13:15

-1

Maybe you might try the following regex?

 [^\(]*\(([0-9]+)[)%]?\)

answered Feb 13 '18 at 13:15

lpg

4,897
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score -1 · Answer 2 · answered Feb 13 '18 at 13:33

Following regex can handle one level of nested parenthesis (to match any number of level a recursive regex should be used but it's not supported by java).

Regex

(?<=Max\()[^()]*(?:\([^()]*\)[^()]*)*(?=\))

Java code

String str = "Max(percentage(%))";
Pattern pattern = Pattern.compile("(?<=Max\\()[^()]*(?:\\([^()]*\\)[^()]*)*(?=\\))");

score -1 · Answer 3 · answered Feb 13 '18 at 14:05

I would say use "or" operator | to check whether you have a percentage or a percentage plus (%):

    String str1 = "Max(32)";
    String str2 = "Max(32(%))";

    Pattern pattern = Pattern.compile("Max\\((.+|.+\\(%\\))\\)");

    Matcher matcher1 = pattern.matcher(str1);
    if (matcher1.find()) {
        System.out.println("percentage = " + matcher1.group(1));
    }

    Matcher matcher2 = pattern.matcher(str2);
    if (matcher2.find()) {
        System.out.println("percentage(%) = " + matcher2.group(1));
    }

Java regex issue to get data in the brackets

3 Answers3