How do I check if a character representing a number?

/**---------------------------------------------------------*
 *     @author Madarapu Naveen                              *
 *    http://madarapunaveen.blogspot.com                    *
 * ---------------------------------------------------------*
 */

public class CharacterIsDigit {
    public static void main(String[] args) {
        String numbers = "1234567890";
        for (int i = 0; i < numbers.length(); i++) {
            if (Character.isDigit(numbers.charAt(i))) {
                System.out.println(numbers.charAt(i)
                        + " is a number.");
            }
            else {
                System.out.println(numbers.charAt(i)
                        + " not a number.");
            }
        }
    }
}