final Map<String, List<Integer>> listenerResults = new HashMap<String, List<Integer>>();
final Semaphore semaphore = new Semaphore(1);
semaphore.acquire();
JobTracker tracker = client.getJobTracker("default");
Job<Integer, Integer> job = tracker.newJob(KeyValueSource.fromMap(m1));
ICompletableFuture<Map<String, List<Integer>>> future = job.onKeys(50).mapper(new TestMapper()).submit();
future.andThen(new ExecutionCallback<Map<String, List<Integer>>>() {
@Override
public void onResponse(Map<String, List<Integer>> response) {