New password pattern verification

Question

Need to develop a class that will verify new passwords against specific patterns. Such as requiring mixed case, at least one numeric character, not having the same character twice, etc. Think Oracle...
Anyone done this sort of thing? Not sure where to start...

Answer 1

Not sure where to start...Too much cold beer?
public void check(String pass) {
        int idx = 0;
        boolean numeric = false;
        boolean upperCase = false;
        boolean lowerCase = false;
        char last = 0;
        while (idx < pass.length()) {
            char ch = pass.charAt(idx++);
            upperCase |= Character.isUpperCase(ch);
            lowerCase |= Character.isLowerCase(ch);
            numeric |= Character.isDigit(ch);
            if (last != 0) {
                if (last == ch)
                    System.out.println("repeated " + last);
            last = ch;
        if (! upperCase)
            System.out.println("need at least one upper case character");
        if (! lowerCase)
            System.out.println("need at least one lower case character");
        if (! numeric)
            System.out.println("need at least one numeric character");
        if (pass.length() < 5)
            System.out.println("need at least 5 characters");
}