presto-main/src/main/java/io/prestosql/server/security/KerberosAuthenticator.java/KerberosAuthenticator/shutdown
class KerberosAuthenticator:    @PreDestroy
    public void shutdown()
    {
        try {
            loginContext.logout();
        }
        catch (LoginException e) {
            throw new RuntimeException(e);
        }
    }