PatternSyntaxChecker.java

// https://www.hackerrank.com/challenges/pattern-syntax-checker/problem

import java.util.Scanner;
import java.util.regex.Pattern;
import java.util.regex.PatternSyntaxException;

public class PatternSyntaxChecker {
 public static void main(String[] args) {
 Scanner scanner = new Scanner(System.in);
 int queries = scanner.nextInt();
 scanner.nextLine();

 while (queries-- > 0) {
 String regex = scanner.nextLine();
 if (isValidPattern(regex)) {
 System.out.println("Valid");
 } else {
 System.out.println("Invalid");
 }
 }
 }

 private static boolean isValidPattern(String regex) {
 try {
 Pattern.compile(regex);
 return true;
 } catch (PatternSyntaxException exception) {
 return false;
 }

 }
}