private void connect(Timer timer) throws InterruptedException {
            while (timer.isTimeLeft()) {
                pause();
                target = supervisor.connect(spec);
                // ping to check if connection is working
                Request request = new Request("frt.rpc.ping");
                target.invokeSync(request, Duration.ofSeconds(5));
                if (request.isError()) {
                    logWarning();
                    target.close();
                } else {
                    log.log(Level.FINE, () -> "Successfully connected to '" + spec + "', this = " + System.identityHashCode(this));
                    pauseTime = 0;
                    logCount = 0;
                    return;
                }
            }
        }
Retrieves the path to a file or directory on the local file system
that has been transferred with the vespa file distribution
mechanism.

Intended to be the only real implementation of FileAcquirer.

@author Tony Vaagenes
fileacquirer/src/main/java/com/yahoo/filedistribution/fileacquirer/FileAcquirerImpl.java