Online Java Compiler By
JavaTpoint.com
import java.util.regex.*; class RegexExample5{ public static void main(String args[]){ System.out.println("metacharacters d....");\\d means digit System.out.println(Pattern.matches("\\d", "abc"));//false (non-digit) System.out.println(Pattern.matches("\\d", "1"));//true (digit and comes once) System.out.println(Pattern.matches("\\d", "4443"));//false (digit but comes more than once) System.out.println(Pattern.matches("\\d", "323abc"));//false (digit and char) System.out.println("metacharacters D....");\\D means non-digit System.out.println(Pattern.matches("\\D", "abc"));//false (non-digit but comes more than once) System.out.println(Pattern.matches("\\D", "1"));//false (digit) System.out.println(Pattern.matches("\\D", "4443"));//false (digit) System.out.println(Pattern.matches("\\D", "323abc"));//false (digit and char) System.out.println(Pattern.matches("\\D", "m"));//true (non-digit and comes once) System.out.println("metacharacters D with quantifier...."); System.out.println(Pattern.matches("\\D*", "mak"));//true (non-digit and may come 0 or more times) }}
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