Quantifier Plus Sign
A quantifier following a subsequence of a pattern determines the possibilities for how that subsequence of a pattern can repeat. Let’s take an example. Suppose you want to find specific character in a string. If you take the simplest case, we can say an character is an arbitrary sequence of one or more characters. The quantifier for one or more is the meta-character “+”. For example, the following program uses the + quantifier to match any arbitrarily long sequence of ‘A’s. The output shows, the regular expression pattern “A+” matches any arbitrarily long sequence of ‘A’s.
Program
import java.util.regex.Pattern; import java.util.regex.Matcher; public class Javaapp { public static void main(String[] args) { Pattern pat = Pattern.compile("A+"); Matcher mat = pat.matcher("A2AA3AAA4AAAA5"); int i = 0; while(mat.find()) { i++; System.out.println(i+"th subsequence : "+mat.group()); } } }