class AuthenticationService {

    public String getLtpaToken(String jwtToken) {
        // remove sign to avoid validation of sign
        final String withoutSign = removeSign(jwtToken);

        // parse to claims and construct QueryResponse
        try {
            return Jwts.parserBuilder()
                .build()
                .parseClaimsJwt(withoutSign)
                .getBody()
                .get(LTPA_CLAIM_NAME, String.class);
        } catch (RuntimeException exception) {
            throw handleJwtParserException(exception);
        }
    }

}