How do I use possessive quantifier regex?

The possessive quantifiers always eat the entire input string, trying once (and only once) for a match. Unlike the greedy quantifiers, possessive quantifiers never back off, even if doing so would allow the overall match to succeed.

package org.kodejava.example.util.regex;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class PossessiveQuantifierDemo {
    public static void main(String[] args) {
        String[] regexs = {
                "x?+",
                "x*+",
                "x++",
                "x{2}+",
                "x{2,}+",
                "x{2,5}+"
        };
        String input = "xxxxxxx";

        for (String r : regexs) {
            Pattern pattern = Pattern.compile(r);
            Matcher matcher = pattern.matcher(input);

            //
            // Find every match and print it
            //
            System.out.println("------------------------------");
            System.out.format("Regex:  %s %n", r);
            while (matcher.find()) {
                System.out.format("Text "%s" found at %d to %d.%n",
                        matcher.group(), matcher.start(), 
                        matcher.end());
            }
        }
    }
}
Wayan Saryada

Wayan Saryada

A programmer, runner, recreational diver, currently living in the island of Bali, Indonesia. Mostly programming in Java, creating web based application with Spring Framework, JPA, etc. If you need help on Java programming you can hire me on Fiverr.
Wayan Saryada

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