validate IPv4 address

IPv4Validator.java

import java.util.InputMismatchException;
import java.util.Scanner;
import java.util.regex.*;

public class IPv4Validator {

    private String ipv4;
    private final String IPv4Regex = "\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}";

    IPv4Validator(String ipv4) {

        this.ipv4 = ipv4;
    }

    public boolean isValid() {
        return isPatternValid() && AreNumbersValid();
    }

    private boolean isPatternValid() {
        boolean isPatternValid = false;
        try {
            isPatternValid = Pattern.matches(IPv4Regex, ipv4);
        } catch (PatternSyntaxException e) {
            System.out.print(e.getMessage());
        }
        return isPatternValid;
    }

    private boolean AreNumbersValid() {
        Scanner scanner = null;
        try {
            scanner = new Scanner(ipv4).useDelimiter(Pattern.compile("\\."));
            for (int i : new int[]{1, 2, 3, 4}) {
                int octet = scanner.nextInt();
                if (octet < 0 || octet > 256) {
                    System.out.println(toOrdinal(i) + " number is wrong");
                    return false;
                }
            }
        } catch (InputMismatchException e) {
            System.out.println(e.getMessage());
        } finally {
            if(scanner != null)
                scanner.close();
        }
        return true;
    }

    private String toOrdinal(int i) {
        switch (i) {
            case 1: return "1st";
            case 2: return "2nd";
            case 3: return "3rd";
            default: return Integer.toString(i) + "th";
        }
    }
}