org.apache.flink.streaming.api.windowing.triggers.Trigger Java Examples

protected WithWindow(DataStream<T1> input1,
		DataStream<T2> input2,
		KeySelector<T1, KEY> keySelector1,
		KeySelector<T2, KEY> keySelector2,
		TypeInformation<KEY> keyType,
		WindowAssigner<? super TaggedUnion<T1, T2>, W> windowAssigner,
		Trigger<? super TaggedUnion<T1, T2>, ? super W> trigger,
		Evictor<? super TaggedUnion<T1, T2>, ? super W> evictor,
		Time allowedLateness) {
	this.input1 = input1;
	this.input2 = input2;

	this.keySelector1 = keySelector1;
	this.keySelector2 = keySelector2;
	this.keyType = keyType;

	this.windowAssigner = windowAssigner;
	this.trigger = trigger;
	this.evictor = evictor;

	this.allowedLateness = allowedLateness;
}
 

public EvictingWindowOperator(WindowAssigner<? super IN, W> windowAssigner,
		TypeSerializer<W> windowSerializer,
		KeySelector<IN, K> keySelector,
		TypeSerializer<K> keySerializer,
		StateDescriptor<? extends ListState<StreamRecord<IN>>, ?> windowStateDescriptor,
		InternalWindowFunction<Iterable<IN>, OUT, K, W> windowFunction,
		Trigger<? super IN, ? super W> trigger,
		Evictor<? super IN, ? super W> evictor,
		long allowedLateness,
		OutputTag<IN> lateDataOutputTag) {

	super(windowAssigner, windowSerializer, keySelector,
		keySerializer, null, windowFunction, trigger, allowedLateness, lateDataOutputTag);

	this.evictor = checkNotNull(evictor);
	this.evictingWindowStateDescriptor = checkNotNull(windowStateDescriptor);
}
 

public EvictingWindowOperator(WindowAssigner<? super IN, W> windowAssigner,
		TypeSerializer<W> windowSerializer,
		KeySelector<IN, K> keySelector,
		TypeSerializer<K> keySerializer,
		StateDescriptor<? extends ListState<StreamRecord<IN>>, ?> windowStateDescriptor,
		InternalWindowFunction<Iterable<IN>, OUT, K, W> windowFunction,
		Trigger<? super IN, ? super W> trigger,
		Evictor<? super IN, ? super W> evictor,
		long allowedLateness,
		OutputTag<IN> lateDataOutputTag) {

	super(windowAssigner, windowSerializer, keySelector,
		keySerializer, null, windowFunction, trigger, allowedLateness, lateDataOutputTag);

	this.evictor = checkNotNull(evictor);
	this.evictingWindowStateDescriptor = checkNotNull(windowStateDescriptor);
}
 

@PublicEvolving
protected WithWindow(DataStream<T1> input1,
		DataStream<T2> input2,
		KeySelector<T1, KEY> keySelector1,
		KeySelector<T2, KEY> keySelector2,
		TypeInformation<KEY> keyType,
		WindowAssigner<? super TaggedUnion<T1, T2>, W> windowAssigner,
		Trigger<? super TaggedUnion<T1, T2>, ? super W> trigger,
		Evictor<? super TaggedUnion<T1, T2>, ? super W> evictor,
		Time allowedLateness) {

	this.input1 = requireNonNull(input1);
	this.input2 = requireNonNull(input2);

	this.keySelector1 = requireNonNull(keySelector1);
	this.keySelector2 = requireNonNull(keySelector2);
	this.keyType = requireNonNull(keyType);

	this.windowAssigner = requireNonNull(windowAssigner);

	this.trigger = trigger;
	this.evictor = evictor;

	this.allowedLateness = allowedLateness;
}
 

private void testNoGarbageCollectionTimerForGlobalWindow(TimeDomainAdaptor timeAdaptor) throws Exception {

		WindowAssigner<Integer, GlobalWindow> mockAssigner = mockGlobalWindowAssigner();
		timeAdaptor.setIsEventTime(mockAssigner);
		Trigger<Integer, GlobalWindow> mockTrigger = mockTrigger();
		InternalWindowFunction<Iterable<Integer>, Void, Integer, GlobalWindow> mockWindowFunction = mockWindowFunction();

		// this needs to be true for the test to succeed
		assertEquals(Long.MAX_VALUE, GlobalWindow.get().maxTimestamp());

		KeyedOneInputStreamOperatorTestHarness<Integer, Integer, Void> testHarness =
				createWindowOperator(mockAssigner, mockTrigger, 0L, mockWindowFunction);

		testHarness.open();

		assertEquals(0, testHarness.getOutput().size());
		assertEquals(0, testHarness.numKeyedStateEntries());

		testHarness.processElement(new StreamRecord<>(0, 0L));

		// just the window contents
		assertEquals(1, testHarness.numKeyedStateEntries());

		// verify we have no timers for either time domain
		assertEquals(0, testHarness.numEventTimeTimers());
		assertEquals(0, testHarness.numProcessingTimeTimers());
	}
 

private static <T> void shouldDeleteProcessingTimeTimerOnElement(Trigger<T, TimeWindow> mockTrigger, final long timestamp) throws Exception {
	doAnswer(new Answer<TriggerResult>() {
		@Override
		public TriggerResult answer(InvocationOnMock invocation) throws Exception {
			@SuppressWarnings("unchecked")
			Trigger.TriggerContext context =
					(Trigger.TriggerContext) invocation.getArguments()[3];
			context.deleteProcessingTimeTimer(timestamp);
			return TriggerResult.CONTINUE;
		}
	})
			.when(mockTrigger).onElement(Matchers.<T>anyObject(), anyLong(), anyTimeWindow(), anyTriggerContext());
}
 

private static <T> void shouldRegisterProcessingTimeTimerOnElement(Trigger<T, TimeWindow> mockTrigger, final long timestamp) throws Exception {
	doAnswer(new Answer<TriggerResult>() {
		@Override
		public TriggerResult answer(InvocationOnMock invocation) throws Exception {
			@SuppressWarnings("unchecked")
			Trigger.TriggerContext context =
					(Trigger.TriggerContext) invocation.getArguments()[3];
			context.registerProcessingTimeTimer(timestamp);
			return TriggerResult.CONTINUE;
		}
	})
			.when(mockTrigger).onElement(Matchers.<T>anyObject(), anyLong(), anyTimeWindow(), anyTriggerContext());
}
 

static <T> void shouldRegisterEventTimeTimerOnElement(Trigger<T, TimeWindow> mockTrigger, final long timestamp) throws Exception {
	doAnswer(new Answer<TriggerResult>() {
		@Override
		public TriggerResult answer(InvocationOnMock invocation) throws Exception {
			@SuppressWarnings("unchecked")
			Trigger.TriggerContext context =
					(Trigger.TriggerContext) invocation.getArguments()[3];
			context.registerEventTimeTimer(timestamp);
			return TriggerResult.CONTINUE;
		}
	})
	.when(mockTrigger).onElement(Matchers.<T>anyObject(), anyLong(), anyTimeWindow(), anyTriggerContext());
}
 

@Test
public void testOnElementPurgeDoesNotCleanupMergingSet() throws Exception {

	MergingWindowAssigner<Integer, TimeWindow> mockAssigner = mockMergingAssigner();
	Trigger<Integer, TimeWindow> mockTrigger = mockTrigger();
	InternalWindowFunction<Iterable<Integer>, Void, Integer, TimeWindow> mockWindowFunction = mockWindowFunction();

	KeyedOneInputStreamOperatorTestHarness<Integer, Integer, Void> testHarness =
			createWindowOperator(mockAssigner, mockTrigger, 0L, mockWindowFunction);

	testHarness.open();

	when(mockAssigner.assignWindows(anyInt(), anyLong(), anyAssignerContext()))
			.thenReturn(Arrays.asList(new TimeWindow(0, 2)));

	assertEquals(0, testHarness.getOutput().size());
	assertEquals(0, testHarness.numKeyedStateEntries());

	doAnswer(new Answer<TriggerResult>() {
		@Override
		public TriggerResult answer(InvocationOnMock invocation) throws Exception {
			return TriggerResult.PURGE;
		}
	}).when(mockTrigger).onElement(Matchers.<Integer>anyObject(), anyLong(), anyTimeWindow(), anyTriggerContext());

	testHarness.processElement(new StreamRecord<>(0, 0L));

	assertEquals(1, testHarness.numKeyedStateEntries()); // the merging window set

	assertEquals(1, testHarness.numEventTimeTimers()); // one cleanup timer

	assertEquals(0, testHarness.getOutput().size());
}
 

public TriggerTestHarness(
		Trigger<T, W> trigger,
		TypeSerializer<W> windowSerializer) throws Exception {
	this.trigger = trigger;
	this.windowSerializer = windowSerializer;

	// we only ever use one key, other tests make sure that windows work across different
	// keys
	DummyEnvironment dummyEnv = new DummyEnvironment("test", 1, 0);
	MemoryStateBackend backend = new MemoryStateBackend();

	@SuppressWarnings("unchecked")
	HeapKeyedStateBackend<Integer> stateBackend = (HeapKeyedStateBackend<Integer>) backend.createKeyedStateBackend(
		dummyEnv,
		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());
	this.stateBackend = stateBackend;

	this.stateBackend.setCurrentKey(KEY);

	this.internalTimerService = new TestInternalTimerService<>(new KeyContext() {
		@Override
		public void setCurrentKey(Object key) {
			// ignore
		}

		@Override
		public Object getCurrentKey() {
			return KEY;
		}
	});
}
 

@Test
public void testProcessingElementsWithinAllowedLateness() throws Exception {
	WindowAssigner<Integer, TimeWindow> mockAssigner = mockTimeWindowAssigner();
	Trigger<Integer, TimeWindow> mockTrigger = mockTrigger();
	InternalWindowFunction<Iterable<Integer>, Void, Integer, TimeWindow> mockWindowFunction = mockWindowFunction();

	KeyedOneInputStreamOperatorTestHarness<Integer, Integer, Void> testHarness =
			createWindowOperator(mockAssigner, mockTrigger, 20L, mockWindowFunction);

	testHarness.open();

	when(mockAssigner.assignWindows(anyInt(), anyLong(), anyAssignerContext()))
			.thenReturn(Arrays.asList(new TimeWindow(0, 2)));

	assertEquals(0, testHarness.getOutput().size());
	assertEquals(0, testHarness.numKeyedStateEntries());

	shouldFireOnElement(mockTrigger);

	// 20 is just at the limit, window.maxTime() is 1 and allowed lateness is 20
	testHarness.processWatermark(new Watermark(20));

	testHarness.processElement(new StreamRecord<>(0, 0L));

	verify(mockWindowFunction, times(1)).process(eq(0), eq(new TimeWindow(0, 2)), anyInternalWindowContext(), intIterable(0), WindowOperatorContractTest.<Void>anyCollector());

	// clear is only called at cleanup time/GC time
	verify(mockTrigger, never()).clear(anyTimeWindow(), anyTriggerContext());

	// FIRE should not purge contents
	assertEquals(1, testHarness.numKeyedStateEntries()); // window contents plus trigger state
	assertEquals(1, testHarness.numEventTimeTimers()); // just the GC timer
}
 

/**
 * Creates a new {@code WindowOperator} based on the given policies and user functions.
 */
public WindowOperator(
		WindowAssigner<? super IN, W> windowAssigner,
		TypeSerializer<W> windowSerializer,
		KeySelector<IN, K> keySelector,
		TypeSerializer<K> keySerializer,
		StateDescriptor<? extends AppendingState<IN, ACC>, ?> windowStateDescriptor,
		InternalWindowFunction<ACC, OUT, K, W> windowFunction,
		Trigger<? super IN, ? super W> trigger,
		long allowedLateness,
		OutputTag<IN> lateDataOutputTag) {

	super(windowFunction);

	checkArgument(!(windowAssigner instanceof BaseAlignedWindowAssigner),
		"The " + windowAssigner.getClass().getSimpleName() + " cannot be used with a WindowOperator. " +
			"This assigner is only used with the AccumulatingProcessingTimeWindowOperator and " +
			"the AggregatingProcessingTimeWindowOperator");

	checkArgument(allowedLateness >= 0);

	checkArgument(windowStateDescriptor == null || windowStateDescriptor.isSerializerInitialized(),
			"window state serializer is not properly initialized");

	this.windowAssigner = checkNotNull(windowAssigner);
	this.windowSerializer = checkNotNull(windowSerializer);
	this.keySelector = checkNotNull(keySelector);
	this.keySerializer = checkNotNull(keySerializer);
	this.windowStateDescriptor = windowStateDescriptor;
	this.trigger = checkNotNull(trigger);
	this.allowedLateness = allowedLateness;
	this.lateDataOutputTag = lateDataOutputTag;

	setChainingStrategy(ChainingStrategy.ALWAYS);
}
 

private static String generateOperatorName(
		WindowAssigner<?, ?> assigner,
		Trigger<?, ?> trigger,
		@Nullable Evictor<?, ?> evictor,
		Function function1,
		@Nullable Function function2) {
	return "Window(" +
		assigner + ", " +
		trigger.getClass().getSimpleName() + ", " +
		(evictor == null ? "" : (evictor.getClass().getSimpleName() + ", ")) +
		generateFunctionName(function1) +
		(function2 == null ? "" : (", " + generateFunctionName(function2))) +
		")";
}
 

static <T> void shouldRegisterEventTimeTimerOnElement(Trigger<T, TimeWindow> mockTrigger, final long timestamp) throws Exception {
	doAnswer(new Answer<TriggerResult>() {
		@Override
		public TriggerResult answer(InvocationOnMock invocation) throws Exception {
			@SuppressWarnings("unchecked")
			Trigger.TriggerContext context =
					(Trigger.TriggerContext) invocation.getArguments()[3];
			context.registerEventTimeTimer(timestamp);
			return TriggerResult.CONTINUE;
		}
	})
	.when(mockTrigger).onElement(Matchers.<T>anyObject(), anyLong(), anyTimeWindow(), anyTriggerContext());
}
 

public TriggerTestHarness(
		Trigger<T, W> trigger,
		TypeSerializer<W> windowSerializer) throws Exception {
	this.trigger = trigger;
	this.windowSerializer = windowSerializer;

	// we only ever use one key, other tests make sure that windows work across different
	// keys
	DummyEnvironment dummyEnv = new DummyEnvironment("test", 1, 0);
	MemoryStateBackend backend = new MemoryStateBackend();

	@SuppressWarnings("unchecked")
	HeapKeyedStateBackend<Integer> stateBackend = (HeapKeyedStateBackend<Integer>) backend.createKeyedStateBackend(
		dummyEnv,
		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());
	this.stateBackend = stateBackend;

	this.stateBackend.setCurrentKey(KEY);

	this.internalTimerService = new TestInternalTimerService<>(new KeyContext() {
		@Override
		public void setCurrentKey(Object key) {
			// ignore
		}

		@Override
		public Object getCurrentKey() {
			return KEY;
		}
	});
}
 

private void testMergingWindowSetClearedAtGarbageCollection(TimeDomainAdaptor timeAdaptor) throws Exception {
	WindowAssigner<Integer, TimeWindow> mockAssigner = mockMergingAssigner();
	timeAdaptor.setIsEventTime(mockAssigner);
	Trigger<Integer, TimeWindow> mockTrigger = mockTrigger();
	InternalWindowFunction<Iterable<Integer>, Void, Integer, TimeWindow> mockWindowFunction = mockWindowFunction();

	KeyedOneInputStreamOperatorTestHarness<Integer, Integer, Void> testHarness =
			createWindowOperator(mockAssigner, mockTrigger, 20L, mockWindowFunction);

	testHarness.open();

	when(mockAssigner.assignWindows(anyInt(), anyLong(), anyAssignerContext()))
			.thenReturn(Arrays.asList(new TimeWindow(0, 20)));

	assertEquals(0, testHarness.getOutput().size());
	assertEquals(0, testHarness.numKeyedStateEntries());

	testHarness.processElement(new StreamRecord<>(0, 0L));

	assertEquals(2, testHarness.numKeyedStateEntries()); // window contents plus merging window set
	assertEquals(1, timeAdaptor.numTimers(testHarness)); // gc timers

	timeAdaptor.advanceTime(testHarness, 19 + 20); // 19 is maxTime of the window

	assertEquals(0, testHarness.numKeyedStateEntries());
	assertEquals(0, timeAdaptor.numTimers(testHarness));
}
 

/**
 * Special method for creating a {@link WindowOperator} with a custom {@link StateDescriptor}
 * for the window contents state.
 */
private <W extends Window, ACC, OUT> KeyedOneInputStreamOperatorTestHarness<Integer, Integer, OUT> createWindowOperator(
		WindowAssigner<Integer, W> assigner,
		Trigger<Integer, W> trigger,
		long allowedLatenss,
		StateDescriptor<? extends AppendingState<Integer, ACC>, ?> stateDescriptor,
		InternalWindowFunction<ACC, OUT, Integer, W> windowFunction) throws Exception {

	KeySelector<Integer, Integer> keySelector = new KeySelector<Integer, Integer>() {
		private static final long serialVersionUID = 1L;

		@Override
		public Integer getKey(Integer value) throws Exception {
			return value;
		}
	};

	@SuppressWarnings("unchecked")
	WindowOperator<Integer, Integer, ACC, OUT, W> operator = new WindowOperator<>(
			assigner,
			assigner.getWindowSerializer(new ExecutionConfig()),
			keySelector,
			IntSerializer.INSTANCE,
			stateDescriptor,
			windowFunction,
			trigger,
			allowedLatenss,
			null /* late output tag */);

	return new KeyedOneInputStreamOperatorTestHarness<>(
			operator,
			keySelector,
			BasicTypeInfo.INT_TYPE_INFO);
}
 

/**
 * Creates a new {@code WindowOperator} based on the given policies and user functions.
 */
public WindowOperator(
		WindowAssigner<? super IN, W> windowAssigner,
		TypeSerializer<W> windowSerializer,
		KeySelector<IN, K> keySelector,
		TypeSerializer<K> keySerializer,
		StateDescriptor<? extends AppendingState<IN, ACC>, ?> windowStateDescriptor,
		InternalWindowFunction<ACC, OUT, K, W> windowFunction,
		Trigger<? super IN, ? super W> trigger,
		long allowedLateness,
		OutputTag<IN> lateDataOutputTag) {

	super(windowFunction);

	checkArgument(!(windowAssigner instanceof BaseAlignedWindowAssigner),
		"The " + windowAssigner.getClass().getSimpleName() + " cannot be used with a WindowOperator. " +
			"This assigner is only used with the AccumulatingProcessingTimeWindowOperator and " +
			"the AggregatingProcessingTimeWindowOperator");

	checkArgument(allowedLateness >= 0);

	checkArgument(windowStateDescriptor == null || windowStateDescriptor.isSerializerInitialized(),
			"window state serializer is not properly initialized");

	this.windowAssigner = checkNotNull(windowAssigner);
	this.windowSerializer = checkNotNull(windowSerializer);
	this.keySelector = checkNotNull(keySelector);
	this.keySerializer = checkNotNull(keySerializer);
	this.windowStateDescriptor = windowStateDescriptor;
	this.trigger = checkNotNull(trigger);
	this.allowedLateness = allowedLateness;
	this.lateDataOutputTag = lateDataOutputTag;

	setChainingStrategy(ChainingStrategy.ALWAYS);
}
 

@Test
public void testLateWindowDropping() throws Exception {
	WindowAssigner<Integer, TimeWindow> mockAssigner = mockTimeWindowAssigner();
	Trigger<Integer, TimeWindow> mockTrigger = mockTrigger();
	InternalWindowFunction<Iterable<Integer>, Void, Integer, TimeWindow> mockWindowFunction = mockWindowFunction();

	KeyedOneInputStreamOperatorTestHarness<Integer, Integer, Void> testHarness =
			createWindowOperator(mockAssigner, mockTrigger, 20L, mockWindowFunction);

	testHarness.open();

	when(mockAssigner.assignWindows(anyInt(), anyLong(), anyAssignerContext()))
			.thenReturn(Arrays.asList(new TimeWindow(0, 2)));

	assertEquals(0, testHarness.getOutput().size());
	assertEquals(0, testHarness.numKeyedStateEntries());

	shouldFireOnElement(mockTrigger);

	// window.maxTime() == 1 plus 20L of allowed lateness
	testHarness.processWatermark(new Watermark(21));

	testHarness.processElement(new StreamRecord<>(0, 0L));

	// there should be nothing
	assertEquals(0, testHarness.numKeyedStateEntries());
	assertEquals(0, testHarness.numEventTimeTimers());
	assertEquals(0, testHarness.numProcessingTimeTimers());

	// there should be two elements now
	assertEquals(0, testHarness.extractOutputStreamRecords().size());
}
 

private void testMergingWindowSetClearedAtGarbageCollection(TimeDomainAdaptor timeAdaptor) throws Exception {
	WindowAssigner<Integer, TimeWindow> mockAssigner = mockMergingAssigner();
	timeAdaptor.setIsEventTime(mockAssigner);
	Trigger<Integer, TimeWindow> mockTrigger = mockTrigger();
	InternalWindowFunction<Iterable<Integer>, Void, Integer, TimeWindow> mockWindowFunction = mockWindowFunction();

	KeyedOneInputStreamOperatorTestHarness<Integer, Integer, Void> testHarness =
			createWindowOperator(mockAssigner, mockTrigger, 20L, mockWindowFunction);

	testHarness.open();

	when(mockAssigner.assignWindows(anyInt(), anyLong(), anyAssignerContext()))
			.thenReturn(Arrays.asList(new TimeWindow(0, 20)));

	assertEquals(0, testHarness.getOutput().size());
	assertEquals(0, testHarness.numKeyedStateEntries());

	testHarness.processElement(new StreamRecord<>(0, 0L));

	assertEquals(2, testHarness.numKeyedStateEntries()); // window contents plus merging window set
	assertEquals(1, timeAdaptor.numTimers(testHarness)); // gc timers

	timeAdaptor.advanceTime(testHarness, 19 + 20); // 19 is maxTime of the window

	assertEquals(0, testHarness.numKeyedStateEntries());
	assertEquals(0, timeAdaptor.numTimers(testHarness));
}
 

private void testOnTimeFire(final TimeDomainAdaptor timeAdaptor) throws Exception {

		WindowAssigner<Integer, TimeWindow> mockAssigner = mockTimeWindowAssigner();
		timeAdaptor.setIsEventTime(mockAssigner);
		Trigger<Integer, TimeWindow> mockTrigger = mockTrigger();
		InternalWindowFunction<Iterable<Integer>, Void, Integer, TimeWindow> mockWindowFunction = mockWindowFunction();

		KeyedOneInputStreamOperatorTestHarness<Integer, Integer, Void> testHarness =
				createWindowOperator(mockAssigner, mockTrigger, 0L, mockWindowFunction);

		testHarness.open();

		timeAdaptor.advanceTime(testHarness, Long.MIN_VALUE);

		when(mockAssigner.assignWindows(anyInt(), anyLong(), anyAssignerContext()))
				.thenReturn(Arrays.asList(new TimeWindow(2, 4), new TimeWindow(0, 2)));

		assertEquals(0, testHarness.extractOutputStreamRecords().size());
		assertEquals(0, testHarness.numKeyedStateEntries());

		doAnswer(new Answer<TriggerResult>() {
			@Override
			public TriggerResult answer(InvocationOnMock invocation) throws Exception {
				Trigger.TriggerContext context = (Trigger.TriggerContext) invocation.getArguments()[3];
				// don't interfere with cleanup timers
				timeAdaptor.registerTimer(context, 0L);
				context.getPartitionedState(valueStateDescriptor).update("hello");
				return TriggerResult.CONTINUE;
			}
		}).when(mockTrigger).onElement(Matchers.<Integer>anyObject(), anyLong(), anyTimeWindow(), anyTriggerContext());

		timeAdaptor.shouldFireOnTime(mockTrigger);

		testHarness.processElement(new StreamRecord<>(0, 0L));

		assertEquals(4, testHarness.numKeyedStateEntries()); // window-contents and trigger state for two windows
		assertEquals(4, timeAdaptor.numTimers(testHarness)); // timers/gc timers for two windows

		timeAdaptor.advanceTime(testHarness, 0L);

		verify(mockWindowFunction, times(2)).process(eq(0), anyTimeWindow(), anyInternalWindowContext(), anyIntIterable(), WindowOperatorContractTest.<Void>anyCollector());
		verify(mockWindowFunction, times(1)).process(eq(0), eq(new TimeWindow(0, 2)), anyInternalWindowContext(), intIterable(0), WindowOperatorContractTest.<Void>anyCollector());
		verify(mockWindowFunction, times(1)).process(eq(0), eq(new TimeWindow(2, 4)), anyInternalWindowContext(), intIterable(0), WindowOperatorContractTest.<Void>anyCollector());

		// clear is only called at cleanup time/GC time
		verify(mockTrigger, never()).clear(anyTimeWindow(), anyTriggerContext());

		// FIRE should not purge contents
		assertEquals(4, testHarness.numKeyedStateEntries());
		assertEquals(2, timeAdaptor.numTimers(testHarness)); // only gc timers left
	}
 

@Override
public void shouldFireOnTime(Trigger<?, TimeWindow> mockTrigger) throws Exception {
	shouldFireOnEventTime(mockTrigger);
}
 

/**
 * Sets the {@code Trigger} that should be used to trigger window emission.
 */
@PublicEvolving
public WithWindow<T1, T2, KEY, W> trigger(Trigger<? super TaggedUnion<T1, T2>, ? super W> newTrigger) {
	return new WithWindow<>(input1, input2, keySelector1, keySelector2, keyType,
			windowAssigner, newTrigger, evictor, allowedLateness);
}
 

private void testOnTimeFire(final TimeDomainAdaptor timeAdaptor) throws Exception {

		WindowAssigner<Integer, TimeWindow> mockAssigner = mockTimeWindowAssigner();
		timeAdaptor.setIsEventTime(mockAssigner);
		Trigger<Integer, TimeWindow> mockTrigger = mockTrigger();
		InternalWindowFunction<Iterable<Integer>, Void, Integer, TimeWindow> mockWindowFunction = mockWindowFunction();

		KeyedOneInputStreamOperatorTestHarness<Integer, Integer, Void> testHarness =
				createWindowOperator(mockAssigner, mockTrigger, 0L, mockWindowFunction);

		testHarness.open();

		timeAdaptor.advanceTime(testHarness, Long.MIN_VALUE);

		when(mockAssigner.assignWindows(anyInt(), anyLong(), anyAssignerContext()))
				.thenReturn(Arrays.asList(new TimeWindow(2, 4), new TimeWindow(0, 2)));

		assertEquals(0, testHarness.extractOutputStreamRecords().size());
		assertEquals(0, testHarness.numKeyedStateEntries());

		doAnswer(new Answer<TriggerResult>() {
			@Override
			public TriggerResult answer(InvocationOnMock invocation) throws Exception {
				Trigger.TriggerContext context = (Trigger.TriggerContext) invocation.getArguments()[3];
				// don't interfere with cleanup timers
				timeAdaptor.registerTimer(context, 0L);
				context.getPartitionedState(valueStateDescriptor).update("hello");
				return TriggerResult.CONTINUE;
			}
		}).when(mockTrigger).onElement(Matchers.<Integer>anyObject(), anyLong(), anyTimeWindow(), anyTriggerContext());

		timeAdaptor.shouldFireOnTime(mockTrigger);

		testHarness.processElement(new StreamRecord<>(0, 0L));

		assertEquals(4, testHarness.numKeyedStateEntries()); // window-contents and trigger state for two windows
		assertEquals(4, timeAdaptor.numTimers(testHarness)); // timers/gc timers for two windows

		timeAdaptor.advanceTime(testHarness, 0L);

		verify(mockWindowFunction, times(2)).process(eq(0), anyTimeWindow(), anyInternalWindowContext(), anyIntIterable(), WindowOperatorContractTest.<Void>anyCollector());
		verify(mockWindowFunction, times(1)).process(eq(0), eq(new TimeWindow(0, 2)), anyInternalWindowContext(), intIterable(0), WindowOperatorContractTest.<Void>anyCollector());
		verify(mockWindowFunction, times(1)).process(eq(0), eq(new TimeWindow(2, 4)), anyInternalWindowContext(), intIterable(0), WindowOperatorContractTest.<Void>anyCollector());

		// clear is only called at cleanup time/GC time
		verify(mockTrigger, never()).clear(anyTimeWindow(), anyTriggerContext());

		// FIRE should not purge contents
		assertEquals(4, testHarness.numKeyedStateEntries());
		assertEquals(2, timeAdaptor.numTimers(testHarness)); // only gc timers left
	}
 

static Trigger.TriggerContext anyTriggerContext() {
	return Mockito.any();
}
 

/**
 * A misbehaving {@code WindowAssigner} can cause a window to become late by merging if
 * it moves the end-of-window time before the watermark. This verifies that we don't allow that.
 */
void testRejectShrinkingMergingWindows(final TimeDomainAdaptor timeAdaptor) throws Exception {
	int allowedLateness = 10;

	if (timeAdaptor instanceof ProcessingTimeAdaptor) {
		// we don't have allowed lateness for processing time
		allowedLateness = 0;
	}

	MergingWindowAssigner<Integer, TimeWindow> mockAssigner = mockMergingAssigner();
	timeAdaptor.setIsEventTime(mockAssigner);
	Trigger<Integer, TimeWindow> mockTrigger = mockTrigger();
	InternalWindowFunction<Iterable<Integer>, Void, Integer, TimeWindow> mockWindowFunction = mockWindowFunction();

	KeyedOneInputStreamOperatorTestHarness<Integer, Integer, Void> testHarness =
			createWindowOperator(mockAssigner, mockTrigger, allowedLateness, mockWindowFunction);

	testHarness.open();

	timeAdaptor.advanceTime(testHarness, 0);

	assertEquals(0, testHarness.extractOutputStreamRecords().size());
	assertEquals(0, testHarness.numKeyedStateEntries());

	when(mockAssigner.assignWindows(anyInt(), anyLong(), anyAssignerContext()))
			.thenReturn(Arrays.asList(new TimeWindow(0, 22)));

	testHarness.processElement(new StreamRecord<>(0, 0L));

	assertEquals(2, testHarness.numKeyedStateEntries()); // window contents and merging window set
	assertEquals(1, timeAdaptor.numTimers(testHarness)); // cleanup timer

	when(mockAssigner.assignWindows(anyInt(), anyLong(), anyAssignerContext()))
			.thenReturn(Arrays.asList(new TimeWindow(0, 25)));

	timeAdaptor.advanceTime(testHarness, 20);

	// our window should still be there
	assertEquals(2, testHarness.numKeyedStateEntries()); // window contents and merging window set
	assertEquals(1, timeAdaptor.numTimers(testHarness)); // cleanup timer

	// the result timestamp is ... + 2 because a watermark t says no element with
	// timestamp <= t will come in the future and because window ends are exclusive:
	// a window (0, 12) will have 11 as maxTimestamp. With the watermark at 20, 10 would
	// already be considered late
	shouldMergeWindows(
			mockAssigner,
			new ArrayList<>(Arrays.asList(new TimeWindow(0, 22), new TimeWindow(0, 25))),
			new ArrayList<>(Arrays.asList(new TimeWindow(0, 22), new TimeWindow(0, 25))),
			new TimeWindow(0, 20 - allowedLateness + 2));

	testHarness.processElement(new StreamRecord<>(0, 0L));

	// now merge it to a window that is just late
	when(mockAssigner.assignWindows(anyInt(), anyLong(), anyAssignerContext()))
			.thenReturn(Arrays.asList(new TimeWindow(0, 25)));

	shouldMergeWindows(
			mockAssigner,
			new ArrayList<>(Arrays.asList(new TimeWindow(0, 20 - allowedLateness + 2), new TimeWindow(0, 25))),
			new ArrayList<>(Arrays.asList(new TimeWindow(0, 20 - allowedLateness + 2), new TimeWindow(0, 25))),
			new TimeWindow(0, 20 - allowedLateness + 1));

	expectedException.expect(UnsupportedOperationException.class);
	testHarness.processElement(new StreamRecord<>(0, 0L));
}
 

@Override
public void shouldPurgeOnTime(Trigger<?, TimeWindow> mockTrigger) throws Exception {
	shouldPurgeOnProcessingTime(mockTrigger);
}
 

@SuppressWarnings("unchecked")
@Override
public Trigger<T, TimeWindow> getDefaultTrigger(StreamExecutionEnvironment env) {
	return (Trigger<T, TimeWindow>) ProcessingTimeTrigger.create();
}
 

@Test
public void testOnElementFire() throws Exception {

	WindowAssigner<Integer, TimeWindow> mockAssigner = mockTimeWindowAssigner();
	Trigger<Integer, TimeWindow> mockTrigger = mockTrigger();
	InternalWindowFunction<Iterable<Integer>, Void, Integer, TimeWindow> mockWindowFunction = mockWindowFunction();

	KeyedOneInputStreamOperatorTestHarness<Integer, Integer, Void> testHarness =
			createWindowOperator(mockAssigner, mockTrigger, 0L, mockWindowFunction);

	testHarness.open();

	when(mockAssigner.assignWindows(anyInt(), anyLong(), anyAssignerContext()))
			.thenReturn(Arrays.asList(new TimeWindow(2, 4), new TimeWindow(0, 2)));

	assertEquals(0, testHarness.getOutput().size());
	assertEquals(0, testHarness.numKeyedStateEntries());

	doAnswer(new Answer<TriggerResult>() {
		@Override
		public TriggerResult answer(InvocationOnMock invocation) throws Exception {
			TimeWindow window = (TimeWindow) invocation.getArguments()[2];
			Trigger.TriggerContext context = (Trigger.TriggerContext) invocation.getArguments()[3];
			context.registerEventTimeTimer(window.getEnd());
			context.getPartitionedState(valueStateDescriptor).update("hello");
			return TriggerResult.FIRE;
		}
	}).when(mockTrigger).onElement(Matchers.<Integer>anyObject(), anyLong(), anyTimeWindow(), anyTriggerContext());

	testHarness.processElement(new StreamRecord<>(0, 0L));

	verify(mockWindowFunction, times(2)).process(eq(0), anyTimeWindow(), anyInternalWindowContext(), anyIntIterable(), WindowOperatorContractTest.<Void>anyCollector());
	verify(mockWindowFunction, times(1)).process(eq(0), eq(new TimeWindow(0, 2)), anyInternalWindowContext(), intIterable(0), WindowOperatorContractTest.<Void>anyCollector());
	verify(mockWindowFunction, times(1)).process(eq(0), eq(new TimeWindow(2, 4)), anyInternalWindowContext(), intIterable(0), WindowOperatorContractTest.<Void>anyCollector());

	// clear is only called at cleanup time/GC time
	verify(mockTrigger, never()).clear(anyTimeWindow(), anyTriggerContext());

	// FIRE should not purge contents
	assertEquals(4, testHarness.numKeyedStateEntries()); // window contents plus trigger state
	assertEquals(4, testHarness.numEventTimeTimers()); // window timers/gc timers
}
 

private static <T> void shouldFireAndPurgeOnElement(Trigger<T, TimeWindow> mockTrigger) throws Exception {
	when(mockTrigger.onElement(Matchers.<T>anyObject(), anyLong(), anyTimeWindow(), anyTriggerContext())).thenReturn(TriggerResult.FIRE_AND_PURGE);
}