@Before public void setup() { chain = new BasicKeyChain(); onKeysAdded = new AtomicReference<List<ECKey>>(); onKeysAddedRan = new AtomicBoolean(); chain.addEventListener( new AbstractKeyChainEventListener() { @Override public void onKeysAdded(List<ECKey> keys2) { onKeysAdded.set(keys2); onKeysAddedRan.set(true); } }, Threading.SAME_THREAD); }