org.apache.flink.api.common.typeutils.base.IntSerializer Java Examples

private OneInputStreamOperatorTestHarness<Integer, Object> createTestHarness(
		String topic,
		int maxParallelism,
		int parallelism,
		int subtaskIndex,
		Semantic semantic) throws Exception {
	Properties properties = createProperties();

	FlinkKafkaProducer011<Integer> kafkaProducer = new FlinkKafkaProducer011<>(
		topic,
		integerKeyedSerializationSchema,
		properties,
		semantic);

	return new OneInputStreamOperatorTestHarness<>(
		new StreamSink<>(kafkaProducer),
		maxParallelism,
		parallelism,
		subtaskIndex,
		IntSerializer.INSTANCE,
		new OperatorID(42, 44));
}
 

/**
 * Verify that an empty {@code ValueState} will yield the default value.
 */
@Test
public void testValueStateDefaultValue() throws Exception {
	AbstractKeyedStateBackend<Integer> backend = createKeyedBackend(IntSerializer.INSTANCE);

	ValueStateDescriptor<String> kvId = new ValueStateDescriptor<>("id", String.class, "Hello");

	ValueState<String> state = backend.getPartitionedState(VoidNamespace.INSTANCE, VoidNamespaceSerializer.INSTANCE, kvId);

	backend.setCurrentKey(1);
	assertEquals("Hello", state.value());

	state.update("Ciao");
	assertEquals("Ciao", state.value());

	state.clear();
	assertEquals("Hello", state.value());

	backend.dispose();
}
 

@SuppressWarnings("unchecked")
@Override
protected TupleSerializer<Tuple3<Tuple2<String, Double>, Tuple2<Long, Long>, Tuple2<Integer, Long>>> createSerializer() {
	return new  TupleSerializer<Tuple3<Tuple2<String, Double>, Tuple2<Long, Long>, Tuple2<Integer, Long>>>(
			(Class<Tuple3<Tuple2<String, Double>, Tuple2<Long, Long>, Tuple2<Integer, Long>>>) (Class<?>) Tuple3.class,
			new TypeSerializer[]{
				new TupleSerializer<Tuple2<String, Double>> (
						(Class<Tuple2<String, Double>>) (Class<?>) Tuple2.class,
						new TypeSerializer[]{
								StringSerializer.INSTANCE,
								DoubleSerializer.INSTANCE}),
				new TupleSerializer<Tuple2<Long, Long>> (
						(Class<Tuple2<Long, Long>>) (Class<?>) Tuple2.class,
						new TypeSerializer[]{
								LongSerializer.INSTANCE,
								LongSerializer.INSTANCE}),
				new TupleSerializer<Tuple2<Integer, Long>> (
						(Class<Tuple2<Integer, Long>>) (Class<?>) Tuple2.class,
						new TypeSerializer[]{
								IntSerializer.INSTANCE,
								LongSerializer.INSTANCE})
			});
}
 

@Test
public void testBroadcastStateRegistrationFailsIfNewKeySerializerIsIncompatible() throws Exception {
	final String stateName = "broadcast-state";

	try {
		testBroadcastStateKeyUpgrade(
			new MapStateDescriptor<>(
				stateName,
				new TestType.V1TestTypeSerializer(),
				IntSerializer.INSTANCE),
			new MapStateDescriptor<>(
				stateName,
				// new key serializer is incompatible
				new TestType.IncompatibleTestTypeSerializer(),
				IntSerializer.INSTANCE));

		Assert.fail("should have failed.");
	} catch (Exception e) {
		Assert.assertTrue(ExceptionUtils.findThrowable(e, StateMigrationException.class).isPresent());
	}
}
 

@Override
public void initializeState(FunctionInitializationContext context) throws Exception {
	Preconditions.checkState(this.checkpointedState == null,
		"The " + getClass().getSimpleName() + " has already been initialized.");

	this.checkpointedState = context.getOperatorStateStore().getListState(
		new ListStateDescriptor<>(
			"from-elements-state",
			IntSerializer.INSTANCE
		)
	);

	if (context.isRestored()) {
		List<Integer> retrievedStates = new ArrayList<>();
		for (Integer entry : this.checkpointedState.get()) {
			retrievedStates.add(entry);
		}

		// given that the parallelism of the function is 1, we can only have 1 state
		Preconditions.checkArgument(retrievedStates.size() == 1,
			getClass().getSimpleName() + " retrieved invalid state.");

		this.numElementsToSkip = retrievedStates.get(0);
	}
}
 

@Test
public void testValueStateWorkWithTtl() throws Exception {
	AbstractKeyedStateBackend<Integer> backend = createKeyedBackend(IntSerializer.INSTANCE);
	try {
		ValueStateDescriptor<MutableLong> kvId = new ValueStateDescriptor<>("id", MutableLong.class);
		kvId.enableTimeToLive(StateTtlConfig.newBuilder(Time.seconds(1)).build());

		ValueState<MutableLong> state = backend.getPartitionedState(VoidNamespace.INSTANCE, VoidNamespaceSerializer.INSTANCE, kvId);
		backend.setCurrentKey(1);
		state.update(new MutableLong());
		state.value();
	} finally {
		backend.close();
		backend.dispose();
	}
}
 

/**
 * Verifies deserialization failure cases when reading a serializer from bytes, in the
 * case of a {@link InvalidClassException}.
 */
@Test
public void testSerializerSerializationWithInvalidClass() throws Exception {

	TypeSerializer<?> serializer = IntSerializer.INSTANCE;

	byte[] serialized;
	try (ByteArrayOutputStreamWithPos out = new ByteArrayOutputStreamWithPos()) {
		TypeSerializerSerializationUtil.writeSerializer(new DataOutputViewStreamWrapper(out), serializer);
		serialized = out.toByteArray();
	}

	TypeSerializer<?> deserializedSerializer;

	try (ByteArrayInputStreamWithPos in = new ByteArrayInputStreamWithPos(serialized)) {
		deserializedSerializer = TypeSerializerSerializationUtil.tryReadSerializer(
			new DataInputViewStreamWrapper(in),
			new ArtificialCNFExceptionThrowingClassLoader(
				Thread.currentThread().getContextClassLoader(),
				Collections.singleton(IntSerializer.class.getName())),
			true);
	}
	Assert.assertTrue(deserializedSerializer instanceof UnloadableDummyTypeSerializer);
}
 

private static InternalTimerServiceImpl<Integer, String> createAndStartInternalTimerService(
		Triggerable<Integer, String> triggerable,
		KeyContext keyContext,
		ProcessingTimeService processingTimeService,
		KeyGroupRange keyGroupList,
		PriorityQueueSetFactory priorityQueueSetFactory) {
	InternalTimerServiceImpl<Integer, String> service = createInternalTimerService(
		keyGroupList,
		keyContext,
		processingTimeService,
		IntSerializer.INSTANCE,
		StringSerializer.INSTANCE,
		priorityQueueSetFactory);

	service.startTimerService(IntSerializer.INSTANCE, StringSerializer.INSTANCE, triggerable);
	return service;
}
 

/**
 * Verify that an empty {@code ReduceState} yields {@code null}.
 */
@Test
public void testReducingStateDefaultValue() throws Exception {
	AbstractKeyedStateBackend<Integer> backend = createKeyedBackend(IntSerializer.INSTANCE);

	ReducingStateDescriptor<String> kvId = new ReducingStateDescriptor<>("id", new AppendingReduce(), String.class);

	ReducingState<String> state = backend.getPartitionedState(
			VoidNamespace.INSTANCE,
			VoidNamespaceSerializer.INSTANCE, kvId);

	backend.setCurrentKey(1);
	assertNull(state.get());

	state.add("Ciao");
	assertEquals("Ciao", state.get());

	state.clear();
	assertNull(state.get());

	backend.dispose();
}
 

/**
 * Verify that an empty {@code FoldingState} yields {@code null}.
 */
@Test
public void testFoldingStateDefaultValue() throws Exception {
	AbstractKeyedStateBackend<Integer> backend = createKeyedBackend(IntSerializer.INSTANCE);

	FoldingStateDescriptor<Integer, String> kvId =
			new FoldingStateDescriptor<>("id", "Fold-Initial:", new AppendingFold(), String.class);

	FoldingState<Integer, String> state = backend.getPartitionedState(
			VoidNamespace.INSTANCE,
			VoidNamespaceSerializer.INSTANCE, kvId);

	backend.setCurrentKey(1);
	assertNull(state.get());

	state.add(1);
	state.add(2);
	assertEquals("Fold-Initial:,1,2", state.get());

	state.clear();
	assertNull(state.get());

	backend.dispose();
}
 

@Test
public void testBroadcastStateRegistrationFailsIfNewKeySerializerIsIncompatible() {
	final String stateName = "broadcast-state";

	try {
		testBroadcastStateKeyUpgrade(
			new MapStateDescriptor<>(
				stateName,
				new TestType.V1TestTypeSerializer(),
				IntSerializer.INSTANCE),
			new MapStateDescriptor<>(
				stateName,
				// new key serializer is incompatible
				new TestType.IncompatibleTestTypeSerializer(),
				IntSerializer.INSTANCE));

		fail("should have failed.");
	} catch (Exception e) {
		Assert.assertTrue(ExceptionUtils.findThrowable(e, StateMigrationException.class).isPresent());
	}
}
 

@Test
public void testPartitionHash() {
	// Test for IntValue
	verifyPartitionHashSelectedChannels(50000, 100, RecordType.INTEGER);
	// Test for StringValue
	verifyPartitionHashSelectedChannels(10000, 100, RecordType.STRING);

	// Test hash corner cases
	final TestIntComparator testIntComp = new TestIntComparator();
	final ChannelSelector<SerializationDelegate<Integer>> selector = createChannelSelector(
		ShipStrategyType.PARTITION_HASH, testIntComp, 100);
	final SerializationDelegate<Integer> serializationDelegate = new SerializationDelegate<>(new IntSerializer());

	assertPartitionHashSelectedChannels(selector, serializationDelegate, Integer.MIN_VALUE, 100);
	assertPartitionHashSelectedChannels(selector, serializationDelegate, -1, 100);
	assertPartitionHashSelectedChannels(selector, serializationDelegate, 0, 100);
	assertPartitionHashSelectedChannels(selector, serializationDelegate, 1, 100);
	assertPartitionHashSelectedChannels(selector, serializationDelegate, Integer.MAX_VALUE, 100);
}
 

@Test
public void testKeySerializationAndDeserialization() throws Exception {
	final DataOutputSerializer outputView = new DataOutputSerializer(8);
	final DataInputDeserializer inputView = new DataInputDeserializer();

	// test for key
	for (int orgKey = 0; orgKey < 100; ++orgKey) {
		outputView.clear();
		RocksDBKeySerializationUtils.writeKey(orgKey, IntSerializer.INSTANCE, outputView, false);
		inputView.setBuffer(outputView.getCopyOfBuffer());
		int deserializedKey = RocksDBKeySerializationUtils.readKey(IntSerializer.INSTANCE, inputView, false);
		Assert.assertEquals(orgKey, deserializedKey);

		RocksDBKeySerializationUtils.writeKey(orgKey, IntSerializer.INSTANCE, outputView, true);
		inputView.setBuffer(outputView.getCopyOfBuffer());
		deserializedKey = RocksDBKeySerializationUtils.readKey(IntSerializer.INSTANCE, inputView, true);
		Assert.assertEquals(orgKey, deserializedKey);
	}
}
 

@SuppressWarnings("unchecked")
@Before
public void beforeTest() {
	serializer1 = new TupleSerializer<Tuple2<Integer, String>>(
			(Class<Tuple2<Integer, String>>) (Class<?>) Tuple2.class,
			new TypeSerializer<?>[] { IntSerializer.INSTANCE, StringSerializer.INSTANCE });
	serializer2 = new TupleSerializer<Tuple2<Integer, String>>(
			(Class<Tuple2<Integer, String>>) (Class<?>) Tuple2.class,
			new TypeSerializer<?>[] { IntSerializer.INSTANCE, StringSerializer.INSTANCE });
	comparator1 =  new TupleComparator<Tuple2<Integer, String>>(
			new int[]{0},
			new TypeComparator<?>[] { new IntComparator(true) },
			new TypeSerializer<?>[] { IntSerializer.INSTANCE });
	comparator2 =  new TupleComparator<Tuple2<Integer, String>>(
			new int[]{0},
			new TypeComparator<?>[] { new IntComparator(true) },
			new TypeSerializer<?>[] { IntSerializer.INSTANCE });
	pairComparator = new GenericPairComparator<Tuple2<Integer, String>, Tuple2<Integer, String>>(comparator1, comparator2);
	
	this.memoryManager = new MemoryManager(MEMORY_SIZE, 1);
	this.ioManager = new IOManagerAsync();
}
 

@SuppressWarnings("unchecked")
@Before
public void beforeTest() {
	serializer1 = new TupleSerializer<Tuple2<Integer, String>>(
			(Class<Tuple2<Integer, String>>) (Class<?>) Tuple2.class,
			new TypeSerializer<?>[] { IntSerializer.INSTANCE, StringSerializer.INSTANCE });
	serializer2 = new TupleSerializer<Tuple2<Integer, String>>(
			(Class<Tuple2<Integer, String>>) (Class<?>) Tuple2.class,
			new TypeSerializer<?>[] { IntSerializer.INSTANCE, StringSerializer.INSTANCE });
	comparator1 =  new TupleComparator<Tuple2<Integer, String>>(
			new int[]{0},
			new TypeComparator<?>[] { new IntComparator(true) },
			new TypeSerializer<?>[] { IntSerializer.INSTANCE });
	comparator2 =  new TupleComparator<Tuple2<Integer, String>>(
			new int[]{0},
			new TypeComparator<?>[] { new IntComparator(true) },
			new TypeSerializer<?>[] { IntSerializer.INSTANCE });
	pairComparator = new GenericPairComparator<Tuple2<Integer, String>, Tuple2<Integer, String>>(comparator1, comparator2);

	this.memoryManager = new MemoryManager(MEMORY_SIZE, 1);
	this.ioManager = new IOManagerAsync();
}
 

@Test
public void testBroadcastStateRegistrationFailsIfNewValueSerializerIsIncompatible() throws Exception {
	final String stateName = "broadcast-state";

	try {
		testBroadcastStateValueUpgrade(
			new MapStateDescriptor<>(
				stateName,
				IntSerializer.INSTANCE,
				new TestType.V1TestTypeSerializer()),
			new MapStateDescriptor<>(
				stateName,
				IntSerializer.INSTANCE,
				// new value serializer is incompatible
				new TestType.IncompatibleTestTypeSerializer()));

		Assert.fail("should have failed.");
	} catch (Exception e) {
		Assert.assertTrue(ExceptionUtils.findThrowable(e, StateMigrationException.class).isPresent());
	}
}
 

@Test
public void testRestoreSerializerWithSameFields() {
	final PojoSerializerSnapshot<TestPojo> testSnapshot = buildTestSnapshot(Arrays.asList(
		ID_FIELD,
		NAME_FIELD,
		HEIGHT_FIELD
	));

	final TypeSerializer<TestPojo> restoredSerializer = testSnapshot.restoreSerializer();
	assertSame(restoredSerializer.getClass(), PojoSerializer.class);
	final PojoSerializer<TestPojo> restoredPojoSerializer = (PojoSerializer<TestPojo>) restoredSerializer;

	final Field[] restoredFields = restoredPojoSerializer.getFields();
	assertArrayEquals(
		new Field[] { ID_FIELD.field, NAME_FIELD.field, HEIGHT_FIELD.field },
		restoredFields);

	final TypeSerializer<?>[] restoredFieldSerializers = restoredPojoSerializer.getFieldSerializers();
	assertArrayEquals(
		new TypeSerializer[] { IntSerializer.INSTANCE, StringSerializer.INSTANCE, DoubleSerializer.INSTANCE },
		restoredFieldSerializers);
}
 

@Override
protected OneInputStreamOperatorTestHarness<Integer, Object> createTestHarness() throws Exception {
	FlinkKafkaProducer011<Integer> kafkaProducer = new FlinkKafkaProducer011<>(
		TOPIC,
		integerKeyedSerializationSchema,
		createProperties(),
		FlinkKafkaProducer011.Semantic.EXACTLY_ONCE
	).ignoreFailuresAfterTransactionTimeout();

	return new OneInputStreamOperatorTestHarness<>(
		new StreamSink<>(kafkaProducer),
		1,
		1,
		0,
		IntSerializer.INSTANCE,
		new OperatorID(1, 1));
}
 

/**
 * Verify that an empty {@code ValueState} will yield the default value.
 */
@Test
public void testValueStateDefaultValue() throws Exception {
	AbstractKeyedStateBackend<Integer> backend = createKeyedBackend(IntSerializer.INSTANCE);

	ValueStateDescriptor<String> kvId = new ValueStateDescriptor<>("id", String.class, "Hello");

	ValueState<String> state = backend.getPartitionedState(VoidNamespace.INSTANCE, VoidNamespaceSerializer.INSTANCE, kvId);

	backend.setCurrentKey(1);
	assertEquals("Hello", state.value());

	state.update("Ciao");
	assertEquals("Ciao", state.value());

	state.clear();
	assertEquals("Hello", state.value());

	backend.dispose();
}
 

@Test
public void testCopyDefaultValue() throws Exception {
	final AbstractKeyedStateBackend<Integer> backend = createKeyedBackend(IntSerializer.INSTANCE);

	ValueStateDescriptor<IntValue> kvId = new ValueStateDescriptor<>("id", IntValue.class, new IntValue(-1));

	ValueState<IntValue> state = backend.getPartitionedState(VoidNamespace.INSTANCE, VoidNamespaceSerializer.INSTANCE, kvId);

	backend.setCurrentKey(1);
	IntValue default1 = state.value();

	backend.setCurrentKey(2);
	IntValue default2 = state.value();

	assertNotNull(default1);
	assertNotNull(default2);
	assertEquals(default1, default2);
	assertFalse(default1 == default2);

	backend.dispose();
}
 

@SuppressWarnings("unchecked")
@Override
protected TupleSerializer<Tuple3<Integer, Long, Double>> createSerializer() {
	return new TupleSerializer<Tuple3<Integer, Long, Double>>(
			(Class<Tuple3<Integer, Long, Double>>) (Class<?>) Tuple3.class,
			new TypeSerializer[]{
				new IntSerializer(),
				new LongSerializer(),
				new DoubleSerializer()});
}
 

@Test
public void testBroadcastStateKeySerializerReconfiguration() throws Exception {
	final String stateName = "broadcast-state";

	testBroadcastStateKeyUpgrade(
		new MapStateDescriptor<>(
			stateName,
			new TestType.V1TestTypeSerializer(),
			IntSerializer.INSTANCE),
		new MapStateDescriptor<>(
			stateName,
			// new key serializer is a new serializer that requires reconfiguration
			new TestType.ReconfigurationRequiringTestTypeSerializer(),
			IntSerializer.INSTANCE));
}
 

private void testUserExceptionHandling(AsyncDataStream.OutputMode outputMode) throws Exception {
	UserExceptionAsyncFunction asyncWaitFunction = new UserExceptionAsyncFunction();
	long timeout = 2000L;

	AsyncWaitOperator<Integer, Integer> asyncWaitOperator = new AsyncWaitOperator<>(
		asyncWaitFunction,
		TIMEOUT,
		2,
		outputMode);

	final MockEnvironment mockEnvironment = createMockEnvironment();
	mockEnvironment.setExpectedExternalFailureCause(Throwable.class);

	OneInputStreamOperatorTestHarness<Integer, Integer> harness = new OneInputStreamOperatorTestHarness<>(
		asyncWaitOperator,
		IntSerializer.INSTANCE,
		mockEnvironment);

	harness.open();

	synchronized (harness.getCheckpointLock()) {
		harness.processElement(1, 1L);
	}

	synchronized (harness.getCheckpointLock()) {
		harness.close();
	}

	assertTrue(harness.getEnvironment().getActualExternalFailureCause().isPresent());
}
 

@Test
public void fromElementsTest() throws Exception {
	List<Integer> expectedList = Arrays.asList(1, 2, 3);
	List<Integer> actualList = SourceFunctionUtil.runSourceFunction(CommonTestUtils.createCopySerializable(
			new FromElementsFunction<Integer>(
					IntSerializer.INSTANCE,
					1,
					2,
					3)));
	assertEquals(expectedList, actualList);
}
 

@Test
public void testCheckConcurrencyProblemWhenPerformingCheckpointAsync() throws Exception {

	CheckpointStreamFactory streamFactory = createStreamFactory();
	Environment env = new DummyEnvironment();
	AbstractKeyedStateBackend<Integer> backend = createKeyedBackend(IntSerializer.INSTANCE, env);

	ExecutorService executorService = Executors.newScheduledThreadPool(1);
	try {
		long checkpointID = 0;
		List<Future> futureList = new ArrayList();
		for (int i = 0; i < 10; ++i) {
			ValueStateDescriptor<Integer> kvId = new ValueStateDescriptor<>("id" + i, IntSerializer.INSTANCE);
			ValueState<Integer> state = backend.getOrCreateKeyedState(VoidNamespaceSerializer.INSTANCE, kvId);
			((InternalValueState) state).setCurrentNamespace(VoidNamespace.INSTANCE);
			backend.setCurrentKey(i);
			state.update(i);

			futureList.add(runSnapshotAsync(executorService,
				backend.snapshot(checkpointID++, System.currentTimeMillis(), streamFactory, CheckpointOptions.forCheckpointWithDefaultLocation())));
		}

		for (Future future : futureList) {
			future.get(20, TimeUnit.SECONDS);
		}
	} catch (Exception e) {
		fail();
	} finally {
		backend.dispose();
		executorService.shutdown();
	}
}
 

@SuppressWarnings("unchecked")
@Override
protected TupleSerializer<Tuple3<Integer, String, Double>> createSerializer() {
	return new TupleSerializer<Tuple3<Integer, String, Double>>(
			(Class<Tuple3<Integer, String, Double>>) (Class<?>) Tuple3.class,
			new TypeSerializer[]{
				new IntSerializer(),
				new StringSerializer(),
				new DoubleSerializer()});
}
 

@Test
public void testIterator() throws Exception{

	// test for keyGroupPrefixBytes == 1 && ambiguousKeyPossible == false
	testIteratorHelper(IntSerializer.INSTANCE, StringSerializer.INSTANCE, 128, i -> i);

	// test for keyGroupPrefixBytes == 1 && ambiguousKeyPossible == true
	testIteratorHelper(StringSerializer.INSTANCE, StringSerializer.INSTANCE, 128, i -> String.valueOf(i));

	// test for keyGroupPrefixBytes == 2 && ambiguousKeyPossible == false
	testIteratorHelper(IntSerializer.INSTANCE, StringSerializer.INSTANCE, 256, i -> i);

	// test for keyGroupPrefixBytes == 2 && ambiguousKeyPossible == true
	testIteratorHelper(StringSerializer.INSTANCE, StringSerializer.INSTANCE, 256, i -> String.valueOf(i));
}
 

@SuppressWarnings("unchecked")
private static AbstractStreamOperator<?> createListPlainMockOp() throws Exception {

	AbstractStreamOperator<?> operatorMock = mock(AbstractStreamOperator.class);
	ExecutionConfig config = new ExecutionConfig();

	KeyedStateBackend keyedStateBackend = mock(KeyedStateBackend.class);

	DefaultKeyedStateStore keyedStateStore = new DefaultKeyedStateStore(keyedStateBackend, config);

	when(operatorMock.getExecutionConfig()).thenReturn(config);

	doAnswer(new Answer<ListState<String>>() {

		@Override
		public ListState<String> answer(InvocationOnMock invocationOnMock) throws Throwable {
			ListStateDescriptor<String> descr =
					(ListStateDescriptor<String>) invocationOnMock.getArguments()[2];

			AbstractKeyedStateBackend<Integer> backend = new MemoryStateBackend().createKeyedStateBackend(
				new DummyEnvironment("test_task", 1, 0),
				new JobID(),
				"test_op",
				IntSerializer.INSTANCE,
				1,
				new KeyGroupRange(0, 0),
				new KvStateRegistry().createTaskRegistry(new JobID(), new JobVertexID()),
				TtlTimeProvider.DEFAULT,
				new UnregisteredMetricsGroup(),
				Collections.emptyList(),
				new CloseableRegistry());
			backend.setCurrentKey(0);
			return backend.getPartitionedState(VoidNamespace.INSTANCE, VoidNamespaceSerializer.INSTANCE, descr);
		}
	}).when(keyedStateBackend).getPartitionedState(Matchers.any(), any(TypeSerializer.class), any(ListStateDescriptor.class));

	when(operatorMock.getKeyedStateStore()).thenReturn(keyedStateStore);
	when(operatorMock.getOperatorID()).thenReturn(new OperatorID());
	return operatorMock;
}
 

@Test
public void testCheckConcurrencyProblemWhenPerformingCheckpointAsync() throws Exception {

	CheckpointStreamFactory streamFactory = createStreamFactory();
	Environment env = new DummyEnvironment();
	AbstractKeyedStateBackend<Integer> backend = createKeyedBackend(IntSerializer.INSTANCE, env);

	ExecutorService executorService = Executors.newScheduledThreadPool(1);
	try {
		long checkpointID = 0;
		List<Future> futureList = new ArrayList();
		for (int i = 0; i < 10; ++i) {
			ValueStateDescriptor<Integer> kvId = new ValueStateDescriptor<>("id" + i, IntSerializer.INSTANCE);
			ValueState<Integer> state = backend.getOrCreateKeyedState(VoidNamespaceSerializer.INSTANCE, kvId);
			((InternalValueState) state).setCurrentNamespace(VoidNamespace.INSTANCE);
			backend.setCurrentKey(i);
			state.update(i);

			futureList.add(runSnapshotAsync(executorService,
				backend.snapshot(checkpointID++, System.currentTimeMillis(), streamFactory, CheckpointOptions.forCheckpointWithDefaultLocation())));
		}

		for (Future future : futureList) {
			future.get(20, TimeUnit.SECONDS);
		}
	} catch (Exception e) {
		fail();
	} finally {
		backend.dispose();
		executorService.shutdown();
	}
}
 

@SuppressWarnings("unchecked")
@Override
protected TupleSerializer<Tuple3<Integer, String, Double>> createSerializer() {
	return new TupleSerializer<Tuple3<Integer, String, Double>>(
			(Class<Tuple3<Integer, String, Double>>) (Class<?>) Tuple3.class,
			new TypeSerializer[]{
				new IntSerializer(),
				new StringSerializer(),
				new DoubleSerializer()});
}