// select two random nodes
final NetworkManager nodeA = network.get(random.nextInt(network.size() / 2));
final NetworkManager nodeB = network.get(random.nextInt(network.size() / 2) + network.size() / 2);
// generate a random content key
final String contentKey = NetworkTestUtil.randomString();
final Parameters parametersA = new Parameters().setLocationKey(nodeA.getNodeId()).setContentKey(contentKey);
final Parameters parametersB = new Parameters().setLocationKey(nodeB.getNodeId()).setContentKey(contentKey);
// check if selected locations are empty
FutureGet futureGet = nodeA.getDataManager().getUnblocked(parametersB);
futureGet.awaitUninterruptibly();
assertNull(futureGet.getData());