gistfile1.txt

 private boolean isValid(String tag) {
        int alphaCount = 0;
        for (int i = 0; i < tag.length(); i++) {
            final char c = tag.charAt(i);
            if (c == '-') {
                if (alphaCount == 0) {
                    return false;
                }
            } else if (('A' <= c && c <= 'Z') || ('a' <= c && c <= 'z') || ('0' <= c && c <= '9')) {
                alphaCount++;
                if (alphaCount > 8) {
                    return false;
                }
            } else {
                return false;
            }
        }
        return (alphaCount != 0);
    }