final CountDownLatch responseLatch = new CountDownLatch(CLUSTER_SIZE);
final CountDownLatch completeLatch = new CountDownLatch(1);
final String msg = randomString();
Callable callable = new AppendCallable(msg);
MemberSelector selector = new SelectAllMembers();
service.submitToMembers(callable, selector, new MultiExecutionCallback() {
public void onResponse(Member member, Object value) {
if (value.equals(msg + AppendCallable.APPENDAGE)) {
responseLatch.countDown();