private static void verifyInputTokenStringNotTooLarge(String tokenString) {
        if (tokenString.length() > MAX_TOKEN_STRING_LENGTH) {
            throw new IllegalArgumentException("Token string is too long to possibly be a valid token");
        }
    }
Attempts to unwrap a SealedSharedKey opaque token representation that was previously
created by a call to toTokenString().
security-utils/src/main/java/com/yahoo/security/SealedSharedKey.java