loop that checks for digits and hiphens

I have to write a loop that steps through each character of a string checking for a digit and a hyphen in a social security number. how can i write the loop if I have an if statement already made for the other items i have to check for already such as the following code I have. Thanks

if (ssn.length() != 11)
{
throw new SocSecException(" wrong number of characters.");

}

else if (ssn.charAt(3) != '-' || ssn.charAt(6) != '-')
{
throw new SocSecException(" dashes at wrong positions.");
}


else
{
return true;
}

Take a look at this code. Hope it helps:

Code:

---

        public static boolean validSSN(String ssn) {
                for (int i = 0; i < ssn.length(); i++) {
                        if (!Character.isDigit(ssn.charAt(i)) || (ssn.charAt(i) == '-' && (i == 3 || i == 6)))
                                return false;
                }
                return ssn.length() == 11;
        }

---

Split the string then check accordingly, eg. check array ubound which tells if correct number of groups (dashes) exist, check each array element for length and/or datatype (expected number in so and so range), etc etc.