@Override
        public Void get(long timeout, TimeUnit unit) throws InterruptedException, ExecutionException, TimeoutException {
            if (!completed.await(timeout, unit)) {
                throw new TimeoutException("Failed to complete offset write in time");
            }
            if (writeError.get() != null) {
                throw new ExecutionException(writeError.get());
            }
            return null;
        }
If configured to use a connector-specific offset store,
{@link OffsetBackingStore#configure(WorkerConfig) configure} that store.

<p>The worker-global offset store is not modified; it is the caller's responsibility to ensure that it is configured
before calls to {@link #start()}, {@link #get(Collection)} and {@link #set(Map, Callback)} take place.
connect/runtime/src/main/java/org/apache/kafka/connect/storage/ConnectorOffsetBackingStore.java