opendaylight/md-sal/sal-distributed-datastore/src/test/java/org/opendaylight/controller/cluster/datastore/AbstractShardTest.java

   1 /*
   2  * Copyright (c) 2015 Brocade Communications Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.controller.cluster.datastore;
   9
  10 import static org.junit.Assert.assertEquals;
  11 import static org.junit.Assert.assertNotNull;
  12 import static org.junit.Assert.assertTrue;
  13 import static org.junit.Assert.fail;
  14 import static org.mockito.Matchers.any;
  15 import static org.mockito.Mockito.doAnswer;
  16 import static org.mockito.Mockito.doReturn;
  17 import static org.mockito.Mockito.mock;
  18 import static org.opendaylight.controller.cluster.datastore.DataStoreVersions.CURRENT_VERSION;
  19 import static org.opendaylight.controller.cluster.datastore.ShardDataTreeMocking.successfulCanCommit;
  20 import static org.opendaylight.controller.cluster.datastore.ShardDataTreeMocking.successfulCommit;
  21 import static org.opendaylight.controller.cluster.datastore.ShardDataTreeMocking.successfulPreCommit;
  22
  23 import akka.actor.ActorRef;
  24 import akka.actor.PoisonPill;
  25 import akka.actor.Props;
  26 import akka.dispatch.Dispatchers;
  27 import akka.japi.Creator;
  28 import akka.pattern.Patterns;
  29 import akka.testkit.TestActorRef;
  30 import akka.util.Timeout;
  31 import com.google.common.base.Optional;
  32 import com.google.common.primitives.UnsignedLong;
  33 import com.google.common.util.concurrent.FutureCallback;
  34 import com.google.common.util.concurrent.Uninterruptibles;
  35 import java.io.IOException;
  36 import java.util.Collections;
  37 import java.util.HashMap;
  38 import java.util.Map;
  39 import java.util.Set;
  40 import java.util.concurrent.CountDownLatch;
  41 import java.util.concurrent.ExecutionException;
  42 import java.util.concurrent.TimeUnit;
  43 import java.util.concurrent.TimeoutException;
  44 import java.util.concurrent.atomic.AtomicInteger;
  45 import org.junit.After;
  46 import org.junit.Assert;
  47 import org.junit.Before;
  48 import org.opendaylight.controller.cluster.access.concepts.MemberName;
  49 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  50 import org.opendaylight.controller.cluster.datastore.DatastoreContext.Builder;
  51 import org.opendaylight.controller.cluster.datastore.identifiers.ShardIdentifier;
  52 import org.opendaylight.controller.cluster.datastore.messages.BatchedModifications;
  53 import org.opendaylight.controller.cluster.datastore.messages.ForwardedReadyTransaction;
  54 import org.opendaylight.controller.cluster.datastore.modification.MergeModification;
  55 import org.opendaylight.controller.cluster.datastore.modification.MutableCompositeModification;
  56 import org.opendaylight.controller.cluster.datastore.modification.WriteModification;
  57 import org.opendaylight.controller.cluster.datastore.persisted.CommitTransactionPayload;
  58 import org.opendaylight.controller.cluster.datastore.persisted.PreBoronShardDataTreeSnapshot;
  59 import org.opendaylight.controller.cluster.datastore.persisted.ShardSnapshotState;
  60 import org.opendaylight.controller.cluster.raft.ReplicatedLogEntry;
  61 import org.opendaylight.controller.cluster.raft.TestActorFactory;
  62 import org.opendaylight.controller.cluster.raft.persisted.Snapshot;
  63 import org.opendaylight.controller.cluster.raft.utils.InMemoryJournal;
  64 import org.opendaylight.controller.cluster.raft.utils.InMemorySnapshotStore;
  65 import org.opendaylight.controller.md.cluster.datastore.model.CarsModel;
  66 import org.opendaylight.controller.md.cluster.datastore.model.TestModel;
  67 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  68 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
  69 import org.opendaylight.yangtools.yang.data.api.schema.DataContainerChild;
  70 import org.opendaylight.yangtools.yang.data.api.schema.MapEntryNode;
  71 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  72 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTree;
  73 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
  74 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidateNode;
  75 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidateTip;
  76 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
  77 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataValidationFailedException;
  78 import org.opendaylight.yangtools.yang.data.api.schema.tree.ModificationType;
  79 import org.opendaylight.yangtools.yang.data.api.schema.tree.TipProducingDataTree;
  80 import org.opendaylight.yangtools.yang.data.api.schema.tree.TreeType;
  81 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNodes;
  82 import org.opendaylight.yangtools.yang.data.impl.schema.tree.InMemoryDataTreeFactory;
  83 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  84 import scala.concurrent.Await;
  85 import scala.concurrent.Future;
  86 import scala.concurrent.duration.Duration;
  87
  88 /**
  89  * Abstract base for shard unit tests.
  90  *
  91  * @author Thomas Pantelis
  92  */
  93 public abstract class AbstractShardTest extends AbstractActorTest {
  94     protected static final SchemaContext SCHEMA_CONTEXT = TestModel.createTestContext();
  95
  96     private static final AtomicInteger NEXT_SHARD_NUM = new AtomicInteger();
  97
  98     protected final ShardIdentifier shardID = ShardIdentifier.create("inventory", MemberName.forName("member-1"),
  99         "config" + NEXT_SHARD_NUM.getAndIncrement());
 100
 101     protected final Builder dataStoreContextBuilder = DatastoreContext.newBuilder()
 102             .shardJournalRecoveryLogBatchSize(3).shardSnapshotBatchCount(5000).shardHeartbeatIntervalInMillis(100);
 103
 104     protected final TestActorFactory actorFactory = new TestActorFactory(getSystem());
 105
 106     @Before
 107     public void setUp() {
 108         InMemorySnapshotStore.clear();
 109         InMemoryJournal.clear();
 110     }
 111
 112     @After
 113     public void tearDown() {
 114         InMemorySnapshotStore.clear();
 115         InMemoryJournal.clear();
 116         actorFactory.close();
 117     }
 118
 119     protected DatastoreContext newDatastoreContext() {
 120         return dataStoreContextBuilder.build();
 121     }
 122
 123     protected Props newShardProps() {
 124         return newShardBuilder().props();
 125     }
 126
 127     protected Shard.Builder newShardBuilder() {
 128         return Shard.builder().id(shardID).datastoreContext(newDatastoreContext()).schemaContext(SCHEMA_CONTEXT);
 129     }
 130
 131     protected void testRecovery(final Set<Integer> listEntryKeys) throws Exception {
 132         // Create the actor and wait for recovery complete.
 133
 134         final int nListEntries = listEntryKeys.size();
 135
 136         final CountDownLatch recoveryComplete = new CountDownLatch(1);
 137
 138         final Creator<Shard> creator = () -> new Shard(newShardBuilder()) {
 139             @Override
 140             protected void onRecoveryComplete() {
 141                 try {
 142                     super.onRecoveryComplete();
 143                 } finally {
 144                     recoveryComplete.countDown();
 145                 }
 146             }
 147         };
 148
 149         final TestActorRef<Shard> shard = TestActorRef.create(getSystem(),
 150                 Props.create(new DelegatingShardCreator(creator)).withDispatcher(Dispatchers.DefaultDispatcherId()),
 151                 "testRecovery");
 152
 153         assertEquals("Recovery complete", true, recoveryComplete.await(5, TimeUnit.SECONDS));
 154
 155         // Verify data in the data store.
 156
 157         final NormalizedNode<?, ?> outerList = readStore(shard, TestModel.OUTER_LIST_PATH);
 158         assertNotNull(TestModel.OUTER_LIST_QNAME.getLocalName() + " not found", outerList);
 159         assertTrue(TestModel.OUTER_LIST_QNAME.getLocalName() + " value is not Iterable",
 160                 outerList.getValue() instanceof Iterable);
 161         for (final Object entry: (Iterable<?>) outerList.getValue()) {
 162             assertTrue(TestModel.OUTER_LIST_QNAME.getLocalName() + " entry is not MapEntryNode",
 163                     entry instanceof MapEntryNode);
 164             final MapEntryNode mapEntry = (MapEntryNode)entry;
 165             final Optional<DataContainerChild<? extends PathArgument, ?>> idLeaf =
 166                     mapEntry.getChild(new YangInstanceIdentifier.NodeIdentifier(TestModel.ID_QNAME));
 167             assertTrue("Missing leaf " + TestModel.ID_QNAME.getLocalName(), idLeaf.isPresent());
 168             final Object value = idLeaf.get().getValue();
 169             assertTrue("Unexpected value for leaf " + TestModel.ID_QNAME.getLocalName() + ": " + value,
 170                     listEntryKeys.remove(value));
 171         }
 172
 173         if (!listEntryKeys.isEmpty()) {
 174             fail("Missing " + TestModel.OUTER_LIST_QNAME.getLocalName() + " entries with keys: " + listEntryKeys);
 175         }
 176
 177         assertEquals("Last log index", nListEntries,
 178                 shard.underlyingActor().getShardMBean().getLastLogIndex());
 179         assertEquals("Commit index", nListEntries,
 180                 shard.underlyingActor().getShardMBean().getCommitIndex());
 181         assertEquals("Last applied", nListEntries,
 182                 shard.underlyingActor().getShardMBean().getLastApplied());
 183
 184         shard.tell(PoisonPill.getInstance(), ActorRef.noSender());
 185     }
 186
 187     protected void verifyLastApplied(final TestActorRef<Shard> shard, final long expectedValue) {
 188         long lastApplied = -1;
 189         for (int i = 0; i < 20 * 5; i++) {
 190             lastApplied = shard.underlyingActor().getShardMBean().getLastApplied();
 191             if (lastApplied == expectedValue) {
 192                 return;
 193             }
 194             Uninterruptibles.sleepUninterruptibly(50, TimeUnit.MILLISECONDS);
 195         }
 196
 197         Assert.fail(String.format("Expected last applied: %d, Actual: %d", expectedValue, lastApplied));
 198     }
 199
 200     protected TipProducingDataTree createDelegatingMockDataTree() throws Exception {
 201         TipProducingDataTree actual = InMemoryDataTreeFactory.getInstance().create(TreeType.CONFIGURATION);
 202         final TipProducingDataTree mock = mock(TipProducingDataTree.class);
 203
 204         doAnswer(invocation -> {
 205             actual.validate(invocation.getArgumentAt(0, DataTreeModification.class));
 206             return null;
 207         }).when(mock).validate(any(DataTreeModification.class));
 208
 209         doAnswer(invocation -> {
 210             return actual.prepare(invocation.getArgumentAt(0, DataTreeModification.class));
 211         }).when(mock).prepare(any(DataTreeModification.class));
 212
 213         doAnswer(invocation -> {
 214             actual.commit(invocation.getArgumentAt(0, DataTreeCandidate.class));
 215             return null;
 216         }).when(mock).commit(any(DataTreeCandidate.class));
 217
 218         doAnswer(invocation -> {
 219             actual.setSchemaContext(invocation.getArgumentAt(0, SchemaContext.class));
 220             return null;
 221         }).when(mock).setSchemaContext(any(SchemaContext.class));
 222
 223         doAnswer(invocation -> {
 224             return actual.takeSnapshot();
 225         }).when(mock).takeSnapshot();
 226
 227         doAnswer(invocation -> {
 228             return actual.getRootPath();
 229         }).when(mock).getRootPath();
 230
 231         return mock;
 232     }
 233
 234     protected ShardDataTreeCohort mockShardDataTreeCohort() {
 235         ShardDataTreeCohort cohort = mock(ShardDataTreeCohort.class);
 236         DataTreeCandidate candidate = mockCandidate("candidate");
 237         successfulCanCommit(cohort);
 238         successfulPreCommit(cohort, candidate);
 239         successfulCommit(cohort);
 240         doReturn(candidate).when(cohort).getCandidate();
 241         return cohort;
 242     }
 243
 244     protected Map<TransactionIdentifier, CapturingShardDataTreeCohort> setupCohortDecorator(final Shard shard,
 245             final TransactionIdentifier... transactionIDs) {
 246         final Map<TransactionIdentifier, CapturingShardDataTreeCohort> cohortMap = new HashMap<>();
 247         for (TransactionIdentifier id: transactionIDs) {
 248             cohortMap.put(id, new CapturingShardDataTreeCohort());
 249         }
 250
 251         shard.getCommitCoordinator().setCohortDecorator((transactionID, actual) -> {
 252             CapturingShardDataTreeCohort cohort = cohortMap.get(transactionID);
 253             cohort.setDelegate(actual);
 254             return cohort;
 255         });
 256
 257         return cohortMap;
 258     }
 259
 260     protected BatchedModifications prepareBatchedModifications(final TransactionIdentifier transactionID,
 261                                                                final MutableCompositeModification modification) {
 262         return prepareBatchedModifications(transactionID, modification, false);
 263     }
 264
 265     protected static BatchedModifications prepareBatchedModifications(final TransactionIdentifier transactionID,
 266                                                              final MutableCompositeModification modification,
 267                                                              final boolean doCommitOnReady) {
 268         final BatchedModifications batchedModifications = new BatchedModifications(transactionID, CURRENT_VERSION);
 269         batchedModifications.addModification(modification);
 270         batchedModifications.setReady(true);
 271         batchedModifications.setDoCommitOnReady(doCommitOnReady);
 272         batchedModifications.setTotalMessagesSent(1);
 273         return batchedModifications;
 274     }
 275
 276     protected static BatchedModifications prepareBatchedModifications(final TransactionIdentifier transactionID,
 277             final YangInstanceIdentifier path, final NormalizedNode<?, ?> data, final boolean doCommitOnReady) {
 278         final MutableCompositeModification modification = new MutableCompositeModification();
 279         modification.addModification(new WriteModification(path, data));
 280         return prepareBatchedModifications(transactionID, modification, doCommitOnReady);
 281     }
 282
 283     protected static ForwardedReadyTransaction prepareForwardedReadyTransaction(final TestActorRef<Shard> shard,
 284             final TransactionIdentifier transactionID, final YangInstanceIdentifier path,
 285             final NormalizedNode<?, ?> data, final boolean doCommitOnReady) {
 286         ReadWriteShardDataTreeTransaction rwTx = shard.underlyingActor().getDataStore()
 287                 .newReadWriteTransaction(transactionID);
 288         rwTx.getSnapshot().write(path, data);
 289         return new ForwardedReadyTransaction(transactionID, CURRENT_VERSION, rwTx, doCommitOnReady);
 290     }
 291
 292     public static NormalizedNode<?,?> readStore(final TestActorRef<? extends Shard> shard,
 293             final YangInstanceIdentifier id) throws ExecutionException, InterruptedException {
 294         return shard.underlyingActor().getDataStore().readNode(id).orNull();
 295     }
 296
 297     public static NormalizedNode<?,?> readStore(final DataTree store, final YangInstanceIdentifier id) {
 298         return store.takeSnapshot().readNode(id).orNull();
 299     }
 300
 301     public void writeToStore(final TestActorRef<Shard> shard, final YangInstanceIdentifier id,
 302             final NormalizedNode<?,?> node) throws InterruptedException, ExecutionException {
 303         Future<Object> future = Patterns.ask(shard, newBatchedModifications(nextTransactionId(),
 304                 id, node, true, true, 1), new Timeout(5, TimeUnit.SECONDS));
 305         try {
 306             Await.ready(future, Duration.create(5, TimeUnit.SECONDS));
 307         } catch (TimeoutException e) {
 308             throw new ExecutionException(e);
 309         }
 310     }
 311
 312     public static void writeToStore(final ShardDataTree store, final YangInstanceIdentifier id,
 313             final NormalizedNode<?,?> node) throws Exception {
 314         BatchedModifications batched = newBatchedModifications(nextTransactionId(), id, node, true, true, 1);
 315         DataTreeModification modification = store.getDataTree().takeSnapshot().newModification();
 316         batched.apply(modification);
 317         store.notifyListeners(store.commit(modification));
 318     }
 319
 320     public static void writeToStore(final DataTree store, final YangInstanceIdentifier id,
 321             final NormalizedNode<?,?> node) throws DataValidationFailedException {
 322         final DataTreeModification transaction = store.takeSnapshot().newModification();
 323
 324         transaction.write(id, node);
 325         transaction.ready();
 326         store.validate(transaction);
 327         final DataTreeCandidate candidate = store.prepare(transaction);
 328         store.commit(candidate);
 329     }
 330
 331     public void mergeToStore(final ShardDataTree store, final YangInstanceIdentifier id,
 332             final NormalizedNode<?,?> node) throws Exception {
 333         final BatchedModifications batched = new BatchedModifications(nextTransactionId(), CURRENT_VERSION);
 334         batched.addModification(new MergeModification(id, node));
 335         batched.setReady(true);
 336         batched.setDoCommitOnReady(true);
 337         batched.setTotalMessagesSent(1);
 338
 339         DataTreeModification modification = store.getDataTree().takeSnapshot().newModification();
 340         batched.apply(modification);
 341         store.notifyListeners(store.commit(modification));
 342     }
 343
 344     DataTree setupInMemorySnapshotStore() throws DataValidationFailedException {
 345         final DataTree testStore = InMemoryDataTreeFactory.getInstance().create(TreeType.OPERATIONAL);
 346         testStore.setSchemaContext(SCHEMA_CONTEXT);
 347
 348         writeToStore(testStore, TestModel.TEST_PATH, ImmutableNodes.containerNode(TestModel.TEST_QNAME));
 349
 350         final NormalizedNode<?, ?> root = readStore(testStore, YangInstanceIdentifier.EMPTY);
 351
 352         InMemorySnapshotStore.addSnapshot(shardID.toString(), Snapshot.create(
 353                 new ShardSnapshotState(new PreBoronShardDataTreeSnapshot(root)),
 354                 Collections.<ReplicatedLogEntry>emptyList(), 0, 1, -1, -1, 1, null, null));
 355         return testStore;
 356     }
 357
 358     static CommitTransactionPayload payloadForModification(final DataTree source, final DataTreeModification mod,
 359             final TransactionIdentifier transactionId) throws DataValidationFailedException, IOException {
 360         source.validate(mod);
 361         final DataTreeCandidate candidate = source.prepare(mod);
 362         source.commit(candidate);
 363         return CommitTransactionPayload.create(transactionId, candidate);
 364     }
 365
 366     static BatchedModifications newBatchedModifications(final TransactionIdentifier transactionID,
 367             final YangInstanceIdentifier path, final NormalizedNode<?, ?> data, final boolean ready,
 368             final boolean doCommitOnReady, final int messagesSent) {
 369         final BatchedModifications batched = new BatchedModifications(transactionID, CURRENT_VERSION);
 370         batched.addModification(new WriteModification(path, data));
 371         batched.setReady(ready);
 372         batched.setDoCommitOnReady(doCommitOnReady);
 373         batched.setTotalMessagesSent(messagesSent);
 374         return batched;
 375     }
 376
 377     @SuppressWarnings("unchecked")
 378     static void verifyOuterListEntry(final TestActorRef<Shard> shard, final Object expIDValue) throws Exception {
 379         final NormalizedNode<?, ?> outerList = readStore(shard, TestModel.OUTER_LIST_PATH);
 380         assertNotNull(TestModel.OUTER_LIST_QNAME.getLocalName() + " not found", outerList);
 381         assertTrue(TestModel.OUTER_LIST_QNAME.getLocalName() + " value is not Iterable",
 382                 outerList.getValue() instanceof Iterable);
 383         final Object entry = ((Iterable<Object>)outerList.getValue()).iterator().next();
 384         assertTrue(TestModel.OUTER_LIST_QNAME.getLocalName() + " entry is not MapEntryNode",
 385                 entry instanceof MapEntryNode);
 386         final MapEntryNode mapEntry = (MapEntryNode)entry;
 387         final Optional<DataContainerChild<? extends PathArgument, ?>> idLeaf =
 388                 mapEntry.getChild(new YangInstanceIdentifier.NodeIdentifier(TestModel.ID_QNAME));
 389         assertTrue("Missing leaf " + TestModel.ID_QNAME.getLocalName(), idLeaf.isPresent());
 390         assertEquals(TestModel.ID_QNAME.getLocalName() + " value", expIDValue, idLeaf.get().getValue());
 391     }
 392
 393     public static DataTreeCandidateTip mockCandidate(final String name) {
 394         final DataTreeCandidateTip mockCandidate = mock(DataTreeCandidateTip.class, name);
 395         final DataTreeCandidateNode mockCandidateNode = mock(DataTreeCandidateNode.class, name + "-node");
 396         doReturn(ModificationType.WRITE).when(mockCandidateNode).getModificationType();
 397         doReturn(Optional.of(ImmutableNodes.containerNode(CarsModel.CARS_QNAME)))
 398                 .when(mockCandidateNode).getDataAfter();
 399         doReturn(CarsModel.BASE_PATH).when(mockCandidate).getRootPath();
 400         doReturn(mockCandidateNode).when(mockCandidate).getRootNode();
 401         return mockCandidate;
 402     }
 403
 404     static DataTreeCandidateTip mockUnmodifiedCandidate(final String name) {
 405         final DataTreeCandidateTip mockCandidate = mock(DataTreeCandidateTip.class, name);
 406         final DataTreeCandidateNode mockCandidateNode = mock(DataTreeCandidateNode.class, name + "-node");
 407         doReturn(ModificationType.UNMODIFIED).when(mockCandidateNode).getModificationType();
 408         doReturn(YangInstanceIdentifier.EMPTY).when(mockCandidate).getRootPath();
 409         doReturn(mockCandidateNode).when(mockCandidate).getRootNode();
 410         return mockCandidate;
 411     }
 412
 413     static void commitTransaction(final DataTree store, final DataTreeModification modification)
 414             throws DataValidationFailedException {
 415         modification.ready();
 416         store.validate(modification);
 417         store.commit(store.prepare(modification));
 418     }
 419
 420     @SuppressWarnings("serial")
 421     public static final class DelegatingShardCreator implements Creator<Shard> {
 422         private final Creator<Shard> delegate;
 423
 424         DelegatingShardCreator(final Creator<Shard> delegate) {
 425             this.delegate = delegate;
 426         }
 427
 428         @Override
 429         public Shard create() throws Exception {
 430             return delegate.create();
 431         }
 432     }
 433
 434     public static class CapturingShardDataTreeCohort extends ShardDataTreeCohort {
 435         private volatile ShardDataTreeCohort delegate;
 436         private FutureCallback<Void> canCommit;
 437         private FutureCallback<DataTreeCandidate> preCommit;
 438         private FutureCallback<UnsignedLong> commit;
 439
 440         public void setDelegate(final ShardDataTreeCohort delegate) {
 441             this.delegate = delegate;
 442         }
 443
 444         public FutureCallback<Void> getCanCommit() {
 445             assertNotNull("canCommit was not invoked", canCommit);
 446             return canCommit;
 447         }
 448
 449         public FutureCallback<DataTreeCandidate> getPreCommit() {
 450             assertNotNull("preCommit was not invoked", preCommit);
 451             return preCommit;
 452         }
 453
 454         public FutureCallback<UnsignedLong> getCommit() {
 455             assertNotNull("commit was not invoked", commit);
 456             return commit;
 457         }
 458
 459         @Override
 460         public TransactionIdentifier getIdentifier() {
 461             return delegate.getIdentifier();
 462         }
 463
 464         @Override
 465         DataTreeCandidateTip getCandidate() {
 466             return delegate.getCandidate();
 467         }
 468
 469         @Override
 470         DataTreeModification getDataTreeModification() {
 471             return delegate.getDataTreeModification();
 472         }
 473
 474         @Override
 475         public void canCommit(final FutureCallback<Void> callback) {
 476             canCommit = mockFutureCallback(callback);
 477             delegate.canCommit(canCommit);
 478         }
 479
 480         @Override
 481         public void preCommit(final FutureCallback<DataTreeCandidate> callback) {
 482             preCommit = mockFutureCallback(callback);
 483             delegate.preCommit(preCommit);
 484         }
 485
 486         @Override
 487         public void commit(final FutureCallback<UnsignedLong> callback) {
 488             commit = mockFutureCallback(callback);
 489             delegate.commit(commit);
 490         }
 491
 492         @SuppressWarnings("unchecked")
 493         private static <T> FutureCallback<T> mockFutureCallback(final FutureCallback<T> actual) {
 494             FutureCallback<T> mock = mock(FutureCallback.class);
 495             doAnswer(invocation -> {
 496                 actual.onFailure(invocation.getArgumentAt(0, Throwable.class));
 497                 return null;
 498             }).when(mock).onFailure(any(Throwable.class));
 499
 500             doAnswer(invocation -> {
 501                 actual.onSuccess((T) invocation.getArgumentAt(0, Throwable.class));
 502                 return null;
 503             }).when(mock).onSuccess((T) any(Object.class));
 504
 505             return mock;
 506         }
 507
 508         @Override
 509         public void abort(final FutureCallback<Void> callback) {
 510             delegate.abort(callback);
 511         }
 512
 513         @Override
 514         public boolean isFailed() {
 515             return delegate.isFailed();
 516         }
 517
 518         @Override
 519         public State getState() {
 520             return delegate.getState();
 521         }
 522     }
 523 }