public static void setupKerberos( OkHttpClient.Builder clientBuilder, String remoteServiceName, boolean useCanonicalHostname, Optional<String> principal, Optional<File> kerberosConfig, Optional<File> keytab, Optional<File> credentialCache) { SpnegoHandler handler = new SpnegoHandler( remoteServiceName, useCanonicalHostname, principal, kerberosConfig, keytab, credentialCache); clientBuilder.addInterceptor(handler); clientBuilder.authenticator(handler); } }