private static void fetchSslTrust(Service sender, HostSpec hostSpec, Operation op, String sslTrustLink, Runnable callbackFunction) { logger.fine("Fetching ssl trust: " + sslTrustLink); Operation fetchSslTrust = Operation.createGet(sender, sslTrustLink) .setCompletion((o, ex) -> { if (ex != null) { logger.severe(ex.getMessage()); failOperation(hostSpec, op, ex); return; } hostSpec.sslTrust = o.getBody(SslTrustCertificateState.class); callbackFunction.run(); }); sender.sendRequest(fetchSslTrust); }