public static boolean isSSN ( String s ) { if ( isEmpty ( s ) ) return defaultEmptyOK ; String normalizedSSN = stripCharsInBag ( s , SSNDelimiters ) ; return ( isInteger ( normalizedSSN ) && normalizedSSN . length ( ) == digitsInSocialSecurityNumber ) ; }
isSSN returns true if string s is a valid U . S . Social Security Number . Must be 9 digits .