org.apache.flink.streaming.api.datastream.WindowedStream Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.flink.streaming.api.datastream;
import org.apache.flink.annotation.Internal;
import org.apache.flink.annotation.Public;
import org.apache.flink.annotation.PublicEvolving;
import org.apache.flink.api.common.functions.AggregateFunction;
import org.apache.flink.api.common.functions.FoldFunction;
import org.apache.flink.api.common.functions.Function;
import org.apache.flink.api.common.functions.ReduceFunction;
import org.apache.flink.api.common.functions.RichFunction;
import org.apache.flink.api.common.state.AggregatingStateDescriptor;
import org.apache.flink.api.common.state.FoldingStateDescriptor;
import org.apache.flink.api.common.state.ListStateDescriptor;
import org.apache.flink.api.common.state.ReducingStateDescriptor;
import org.apache.flink.api.common.typeinfo.TypeInformation;
import org.apache.flink.api.common.typeutils.TypeSerializer;
import org.apache.flink.api.java.Utils;
import org.apache.flink.api.java.functions.KeySelector;
import org.apache.flink.api.java.typeutils.TypeExtractor;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.functions.aggregation.AggregationFunction;
import org.apache.flink.streaming.api.functions.aggregation.ComparableAggregator;
import org.apache.flink.streaming.api.functions.aggregation.SumAggregator;
import org.apache.flink.streaming.api.functions.windowing.AggregateApplyWindowFunction;
import org.apache.flink.streaming.api.functions.windowing.FoldApplyProcessWindowFunction;
import org.apache.flink.streaming.api.functions.windowing.FoldApplyWindowFunction;
import org.apache.flink.streaming.api.functions.windowing.PassThroughWindowFunction;
import org.apache.flink.streaming.api.functions.windowing.ProcessWindowFunction;
import org.apache.flink.streaming.api.functions.windowing.ReduceApplyProcessWindowFunction;
import org.apache.flink.streaming.api.functions.windowing.ReduceApplyWindowFunction;
import org.apache.flink.streaming.api.functions.windowing.WindowFunction;
import org.apache.flink.streaming.api.operators.OneInputStreamOperator;
import org.apache.flink.streaming.api.windowing.assigners.BaseAlignedWindowAssigner;
import org.apache.flink.streaming.api.windowing.assigners.MergingWindowAssigner;
import org.apache.flink.streaming.api.windowing.assigners.WindowAssigner;
import org.apache.flink.streaming.api.windowing.evictors.Evictor;
import org.apache.flink.streaming.api.windowing.time.Time;
import org.apache.flink.streaming.api.windowing.triggers.Trigger;
import org.apache.flink.streaming.api.windowing.windows.Window;
import org.apache.flink.streaming.runtime.operators.windowing.EvictingWindowOperator;
import org.apache.flink.streaming.runtime.operators.windowing.WindowOperator;
import org.apache.flink.streaming.runtime.operators.windowing.functions.InternalAggregateProcessWindowFunction;
import org.apache.flink.streaming.runtime.operators.windowing.functions.InternalIterableProcessWindowFunction;
import org.apache.flink.streaming.runtime.operators.windowing.functions.InternalIterableWindowFunction;
import org.apache.flink.streaming.runtime.operators.windowing.functions.InternalSingleValueProcessWindowFunction;
import org.apache.flink.streaming.runtime.operators.windowing.functions.InternalSingleValueWindowFunction;
import org.apache.flink.streaming.runtime.operators.windowing.functions.InternalWindowFunction;
import org.apache.flink.streaming.runtime.streamrecord.StreamElementSerializer;
import org.apache.flink.streaming.runtime.streamrecord.StreamRecord;
import org.apache.flink.util.OutputTag;
import org.apache.flink.util.Preconditions;
import javax.annotation.Nullable;
import java.lang.reflect.Type;
import static org.apache.flink.util.Preconditions.checkArgument;
import static org.apache.flink.util.Preconditions.checkNotNull;
/**
* A {@code WindowedStream} represents a data stream where elements are grouped by
* key, and for each key, the stream of elements is split into windows based on a
* {@link org.apache.flink.streaming.api.windowing.assigners.WindowAssigner}. Window emission
* is triggered based on a {@link org.apache.flink.streaming.api.windowing.triggers.Trigger}.
*
* The windows are conceptually evaluated for each key individually, meaning windows can trigger
* at different points for each key.
*
*
If an {@link Evictor} is specified it will be used to evict elements from the window after
* evaluation was triggered by the {@code Trigger} but before the actual evaluation of the window.
* When using an evictor window performance will degrade significantly, since
* incremental aggregation of window results cannot be used.
*
*
Note that the {@code WindowedStream} is purely and API construct, during runtime the
* {@code WindowedStream} will be collapsed together with the {@code KeyedStream} and the operation
* over the window into one single operation.
*
* @param The type of elements in the stream.
* @param The type of the key by which elements are grouped.
* @param The type of {@code Window} that the {@code WindowAssigner} assigns the elements to.
*/
@Public
public class WindowedStream {
/** The keyed data stream that is windowed by this stream. */
private final KeyedStream input;
/** The window assigner. */
private final WindowAssigner windowAssigner;
/** The trigger that is used for window evaluation/emission. */
private Trigger trigger;
/** The evictor that is used for evicting elements before window evaluation. */
private Evictor evictor;
/** The user-specified allowed lateness. */
private long allowedLateness = 0L;
/**
* Side output {@code OutputTag} for late data. If no tag is set late data will simply be
* dropped.
*/
private OutputTag lateDataOutputTag;
@PublicEvolving
public WindowedStream(KeyedStream input,
WindowAssigner windowAssigner) {
this.input = input;
this.windowAssigner = windowAssigner;
this.trigger = windowAssigner.getDefaultTrigger(input.getExecutionEnvironment());
}
/**
* Sets the {@code Trigger} that should be used to trigger window emission.
*/
@PublicEvolving
public WindowedStream trigger(Trigger trigger) {
if (windowAssigner instanceof MergingWindowAssigner && !trigger.canMerge()) {
throw new UnsupportedOperationException("A merging window assigner cannot be used with a trigger that does not support merging.");
}
if (windowAssigner instanceof BaseAlignedWindowAssigner) {
throw new UnsupportedOperationException("Cannot use a " + windowAssigner.getClass().getSimpleName() + " with a custom trigger.");
}
this.trigger = trigger;
return this;
}
/**
* Sets the time by which elements are allowed to be late. Elements that
* arrive behind the watermark by more than the specified time will be dropped.
* By default, the allowed lateness is {@code 0L}.
*
* Setting an allowed lateness is only valid for event-time windows.
*/
@PublicEvolving
public WindowedStream allowedLateness(Time lateness) {
final long millis = lateness.toMilliseconds();
checkArgument(millis >= 0, "The allowed lateness cannot be negative.");
this.allowedLateness = millis;
return this;
}
/**
* Send late arriving data to the side output identified by the given {@link OutputTag}. Data
* is considered late after the watermark has passed the end of the window plus the allowed
* lateness set using {@link #allowedLateness(Time)}.
*
* You can get the stream of late data using
* {@link SingleOutputStreamOperator#getSideOutput(OutputTag)} on the
* {@link SingleOutputStreamOperator} resulting from the windowed operation
* with the same {@link OutputTag}.
*/
@PublicEvolving
public WindowedStream sideOutputLateData(OutputTag outputTag) {
Preconditions.checkNotNull(outputTag, "Side output tag must not be null.");
this.lateDataOutputTag = input.getExecutionEnvironment().clean(outputTag);
return this;
}
/**
* Sets the {@code Evictor} that should be used to evict elements from a window before emission.
*
* Note: When using an evictor window performance will degrade significantly, since
* incremental aggregation of window results cannot be used.
*/
@PublicEvolving
public WindowedStream evictor(Evictor evictor) {
if (windowAssigner instanceof BaseAlignedWindowAssigner) {
throw new UnsupportedOperationException("Cannot use a " + windowAssigner.getClass().getSimpleName() + " with an Evictor.");
}
this.evictor = evictor;
return this;
}
// ------------------------------------------------------------------------
// Operations on the keyed windows
// ------------------------------------------------------------------------
/**
* Applies a reduce function to the window. The window function is called for each evaluation
* of the window for each key individually. The output of the reduce function is interpreted
* as a regular non-windowed stream.
*
* This window will try and incrementally aggregate data as much as the window policies
* permit. For example, tumbling time windows can aggregate the data, meaning that only one
* element per key is stored. Sliding time windows will aggregate on the granularity of the
* slide interval, so a few elements are stored per key (one per slide interval).
* Custom windows may not be able to incrementally aggregate, or may need to store extra values
* in an aggregation tree.
*
* @param function The reduce function.
* @return The data stream that is the result of applying the reduce function to the window.
*/
@SuppressWarnings("unchecked")
public SingleOutputStreamOperator reduce(ReduceFunction function) {
if (function instanceof RichFunction) {
throw new UnsupportedOperationException("ReduceFunction of reduce can not be a RichFunction. " +
"Please use reduce(ReduceFunction, WindowFunction) instead.");
}
//clean the closure
function = input.getExecutionEnvironment().clean(function);
return reduce(function, new PassThroughWindowFunction());
}
/**
* Applies the given window function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the window function is
* interpreted as a regular non-windowed stream.
*
* Arriving data is incrementally aggregated using the given reducer.
*
* @param reduceFunction The reduce function that is used for incremental aggregation.
* @param function The window function.
* @return The data stream that is the result of applying the window function to the window.
*/
public SingleOutputStreamOperator reduce(
ReduceFunction reduceFunction,
WindowFunction function) {
TypeInformation inType = input.getType();
TypeInformation resultType = getWindowFunctionReturnType(function, inType);
return reduce(reduceFunction, function, resultType);
}
/**
* Applies the given window function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the window function is
* interpreted as a regular non-windowed stream.
*
* Arriving data is incrementally aggregated using the given reducer.
*
* @param reduceFunction The reduce function that is used for incremental aggregation.
* @param function The window function.
* @param resultType Type information for the result type of the window function.
* @return The data stream that is the result of applying the window function to the window.
*/
public SingleOutputStreamOperator reduce(
ReduceFunction reduceFunction,
WindowFunction function,
TypeInformation resultType) {
if (reduceFunction instanceof RichFunction) {
throw new UnsupportedOperationException("ReduceFunction of reduce can not be a RichFunction.");
}
//clean the closures
function = input.getExecutionEnvironment().clean(function);
reduceFunction = input.getExecutionEnvironment().clean(reduceFunction);
final String opName = generateOperatorName(windowAssigner, trigger, evictor, reduceFunction, function);
KeySelector keySel = input.getKeySelector();
OneInputStreamOperator operator;
if (evictor != null) {
@SuppressWarnings({"unchecked", "rawtypes"})
TypeSerializer> streamRecordSerializer =
(TypeSerializer>) new StreamElementSerializer(input.getType().createSerializer(getExecutionEnvironment().getConfig()));
ListStateDescriptor> stateDesc =
new ListStateDescriptor<>("window-contents", streamRecordSerializer);
operator =
new EvictingWindowOperator<>(windowAssigner,
windowAssigner.getWindowSerializer(getExecutionEnvironment().getConfig()),
keySel,
input.getKeyType().createSerializer(getExecutionEnvironment().getConfig()),
stateDesc,
new InternalIterableWindowFunction<>(new ReduceApplyWindowFunction<>(reduceFunction, function)),
trigger,
evictor,
allowedLateness,
lateDataOutputTag);
} else {
ReducingStateDescriptor stateDesc = new ReducingStateDescriptor<>("window-contents",
reduceFunction,
input.getType().createSerializer(getExecutionEnvironment().getConfig()));
operator =
new WindowOperator<>(windowAssigner,
windowAssigner.getWindowSerializer(getExecutionEnvironment().getConfig()),
keySel,
input.getKeyType().createSerializer(getExecutionEnvironment().getConfig()),
stateDesc,
new InternalSingleValueWindowFunction<>(function),
trigger,
allowedLateness,
lateDataOutputTag);
}
return input.transform(opName, resultType, operator);
}
/**
* Applies the given window function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the window function is
* interpreted as a regular non-windowed stream.
*
* Arriving data is incrementally aggregated using the given reducer.
*
* @param reduceFunction The reduce function that is used for incremental aggregation.
* @param function The window function.
* @return The data stream that is the result of applying the window function to the window.
*/
@PublicEvolving
public SingleOutputStreamOperator reduce(ReduceFunction reduceFunction, ProcessWindowFunction function) {
TypeInformation resultType = getProcessWindowFunctionReturnType(function, input.getType(), null);
return reduce(reduceFunction, function, resultType);
}
/**
* Applies the given window function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the window function is
* interpreted as a regular non-windowed stream.
*
* Arriving data is incrementally aggregated using the given reducer.
*
* @param reduceFunction The reduce function that is used for incremental aggregation.
* @param function The window function.
* @param resultType Type information for the result type of the window function
* @return The data stream that is the result of applying the window function to the window.
*/
@Internal
public SingleOutputStreamOperator reduce(ReduceFunction reduceFunction, ProcessWindowFunction function, TypeInformation resultType) {
if (reduceFunction instanceof RichFunction) {
throw new UnsupportedOperationException("ReduceFunction of apply can not be a RichFunction.");
}
//clean the closures
function = input.getExecutionEnvironment().clean(function);
reduceFunction = input.getExecutionEnvironment().clean(reduceFunction);
final String opName = generateOperatorName(windowAssigner, trigger, evictor, reduceFunction, function);
KeySelector keySel = input.getKeySelector();
OneInputStreamOperator operator;
if (evictor != null) {
@SuppressWarnings({"unchecked", "rawtypes"})
TypeSerializer> streamRecordSerializer =
(TypeSerializer>) new StreamElementSerializer(input.getType().createSerializer(getExecutionEnvironment().getConfig()));
ListStateDescriptor> stateDesc =
new ListStateDescriptor<>("window-contents", streamRecordSerializer);
operator =
new EvictingWindowOperator<>(windowAssigner,
windowAssigner.getWindowSerializer(getExecutionEnvironment().getConfig()),
keySel,
input.getKeyType().createSerializer(getExecutionEnvironment().getConfig()),
stateDesc,
new InternalIterableProcessWindowFunction<>(new ReduceApplyProcessWindowFunction<>(reduceFunction, function)),
trigger,
evictor,
allowedLateness,
lateDataOutputTag);
} else {
ReducingStateDescriptor stateDesc = new ReducingStateDescriptor<>("window-contents",
reduceFunction,
input.getType().createSerializer(getExecutionEnvironment().getConfig()));
operator =
new WindowOperator<>(windowAssigner,
windowAssigner.getWindowSerializer(getExecutionEnvironment().getConfig()),
keySel,
input.getKeyType().createSerializer(getExecutionEnvironment().getConfig()),
stateDesc,
new InternalSingleValueProcessWindowFunction<>(function),
trigger,
allowedLateness,
lateDataOutputTag);
}
return input.transform(opName, resultType, operator);
}
// ------------------------------------------------------------------------
// Fold Function
// ------------------------------------------------------------------------
/**
* Applies the given fold function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the reduce function is
* interpreted as a regular non-windowed stream.
*
* @param function The fold function.
* @return The data stream that is the result of applying the fold function to the window.
*
* @deprecated use {@link #aggregate(AggregationFunction)} instead
*/
@Deprecated
public SingleOutputStreamOperator fold(R initialValue, FoldFunction function) {
if (function instanceof RichFunction) {
throw new UnsupportedOperationException("FoldFunction can not be a RichFunction. " +
"Please use fold(FoldFunction, WindowFunction) instead.");
}
TypeInformation resultType = TypeExtractor.getFoldReturnTypes(function, input.getType(),
Utils.getCallLocationName(), true);
return fold(initialValue, function, resultType);
}
/**
* Applies the given fold function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the reduce function is
* interpreted as a regular non-windowed stream.
*
* @param function The fold function.
* @return The data stream that is the result of applying the fold function to the window.
*
* @deprecated use {@link #aggregate(AggregateFunction, TypeInformation, TypeInformation)} instead
*/
@Deprecated
public SingleOutputStreamOperator fold(R initialValue, FoldFunction function, TypeInformation resultType) {
if (function instanceof RichFunction) {
throw new UnsupportedOperationException("FoldFunction can not be a RichFunction. " +
"Please use fold(FoldFunction, WindowFunction) instead.");
}
return fold(initialValue, function, new PassThroughWindowFunction(), resultType, resultType);
}
/**
* Applies the given window function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the window function is
* interpreted as a regular non-windowed stream.
*
* Arriving data is incrementally aggregated using the given fold function.
*
* @param initialValue The initial value of the fold.
* @param foldFunction The fold function that is used for incremental aggregation.
* @param function The window function.
* @return The data stream that is the result of applying the window function to the window.
*
* @deprecated use {@link #aggregate(AggregateFunction, WindowFunction)} instead
*/
@PublicEvolving
@Deprecated
public SingleOutputStreamOperator fold(ACC initialValue, FoldFunction foldFunction, WindowFunction function) {
TypeInformation foldAccumulatorType = TypeExtractor.getFoldReturnTypes(foldFunction, input.getType(),
Utils.getCallLocationName(), true);
TypeInformation resultType = getWindowFunctionReturnType(function, foldAccumulatorType);
return fold(initialValue, foldFunction, function, foldAccumulatorType, resultType);
}
/**
* Applies the given window function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the window function is
* interpreted as a regular non-windowed stream.
*
* Arriving data is incrementally aggregated using the given fold function.
*
* @param initialValue The initial value of the fold.
* @param foldFunction The fold function that is used for incremental aggregation.
* @param function The window function.
* @param foldAccumulatorType Type information for the result type of the fold function
* @param resultType Type information for the result type of the window function
* @return The data stream that is the result of applying the window function to the window.
*
* @deprecated use {@link #aggregate(AggregateFunction, ProcessWindowFunction, TypeInformation, TypeInformation, TypeInformation)} instead
*/
@PublicEvolving
@Deprecated
public SingleOutputStreamOperator fold(ACC initialValue,
FoldFunction foldFunction,
WindowFunction function,
TypeInformation foldAccumulatorType,
TypeInformation resultType) {
if (foldFunction instanceof RichFunction) {
throw new UnsupportedOperationException("FoldFunction of fold can not be a RichFunction.");
}
if (windowAssigner instanceof MergingWindowAssigner) {
throw new UnsupportedOperationException("Fold cannot be used with a merging WindowAssigner.");
}
if (windowAssigner instanceof BaseAlignedWindowAssigner) {
throw new UnsupportedOperationException("Fold cannot be used with a " +
windowAssigner.getClass().getSimpleName() + " assigner.");
}
//clean the closures
function = input.getExecutionEnvironment().clean(function);
foldFunction = input.getExecutionEnvironment().clean(foldFunction);
final String opName = generateOperatorName(windowAssigner, trigger, evictor, foldFunction, function);
KeySelector keySel = input.getKeySelector();
OneInputStreamOperator operator;
if (evictor != null) {
@SuppressWarnings({"unchecked", "rawtypes"})
TypeSerializer> streamRecordSerializer =
(TypeSerializer>) new StreamElementSerializer(input.getType().createSerializer(getExecutionEnvironment().getConfig()));
ListStateDescriptor> stateDesc =
new ListStateDescriptor<>("window-contents", streamRecordSerializer);
operator = new EvictingWindowOperator<>(windowAssigner,
windowAssigner.getWindowSerializer(getExecutionEnvironment().getConfig()),
keySel,
input.getKeyType().createSerializer(getExecutionEnvironment().getConfig()),
stateDesc,
new InternalIterableWindowFunction<>(new FoldApplyWindowFunction<>(initialValue, foldFunction, function, foldAccumulatorType)),
trigger,
evictor,
allowedLateness,
lateDataOutputTag);
} else {
FoldingStateDescriptor stateDesc = new FoldingStateDescriptor<>("window-contents",
initialValue, foldFunction, foldAccumulatorType.createSerializer(getExecutionEnvironment().getConfig()));
operator = new WindowOperator<>(windowAssigner,
windowAssigner.getWindowSerializer(getExecutionEnvironment().getConfig()),
keySel,
input.getKeyType().createSerializer(getExecutionEnvironment().getConfig()),
stateDesc,
new InternalSingleValueWindowFunction<>(function),
trigger,
allowedLateness,
lateDataOutputTag);
}
return input.transform(opName, resultType, operator);
}
/**
* Applies the given window function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the window function is
* interpreted as a regular non-windowed stream.
*
* Arriving data is incrementally aggregated using the given fold function.
*
* @param initialValue The initial value of the fold.
* @param foldFunction The fold function that is used for incremental aggregation.
* @param windowFunction The window function.
* @return The data stream that is the result of applying the window function to the window.
*
* @deprecated use {@link #aggregate(AggregateFunction, WindowFunction)} instead
*/
@PublicEvolving
@Deprecated
public SingleOutputStreamOperator fold(ACC initialValue, FoldFunction foldFunction, ProcessWindowFunction windowFunction) {
if (foldFunction instanceof RichFunction) {
throw new UnsupportedOperationException("FoldFunction can not be a RichFunction.");
}
TypeInformation foldResultType = TypeExtractor.getFoldReturnTypes(foldFunction, input.getType(),
Utils.getCallLocationName(), true);
TypeInformation windowResultType = getProcessWindowFunctionReturnType(windowFunction, foldResultType, Utils.getCallLocationName());
return fold(initialValue, foldFunction, windowFunction, foldResultType, windowResultType);
}
/**
* Applies the given window function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the window function is
* interpreted as a regular non-windowed stream.
*
* Arriving data is incrementally aggregated using the given fold function.
*
* @param initialValue the initial value to be passed to the first invocation of the fold function
* @param foldFunction The fold function.
* @param foldResultType The result type of the fold function.
* @param windowFunction The process window function.
* @param windowResultType The process window function result type.
* @return The data stream that is the result of applying the fold function to the window.
*
* @deprecated use {@link #aggregate(AggregateFunction, WindowFunction, TypeInformation, TypeInformation, TypeInformation)} instead
*/
@Deprecated
@Internal
public SingleOutputStreamOperator fold(
ACC initialValue,
FoldFunction foldFunction,
ProcessWindowFunction windowFunction,
TypeInformation foldResultType,
TypeInformation windowResultType) {
if (foldFunction instanceof RichFunction) {
throw new UnsupportedOperationException("FoldFunction can not be a RichFunction.");
}
if (windowAssigner instanceof MergingWindowAssigner) {
throw new UnsupportedOperationException("Fold cannot be used with a merging WindowAssigner.");
}
//clean the closures
windowFunction = input.getExecutionEnvironment().clean(windowFunction);
foldFunction = input.getExecutionEnvironment().clean(foldFunction);
final String opName = generateOperatorName(windowAssigner, trigger, evictor, foldFunction, windowFunction);
KeySelector keySel = input.getKeySelector();
OneInputStreamOperator operator;
if (evictor != null) {
@SuppressWarnings({"unchecked", "rawtypes"})
TypeSerializer> streamRecordSerializer =
(TypeSerializer>) new StreamElementSerializer(input.getType().createSerializer(getExecutionEnvironment().getConfig()));
ListStateDescriptor> stateDesc =
new ListStateDescriptor<>("window-contents", streamRecordSerializer);
operator =
new EvictingWindowOperator<>(windowAssigner,
windowAssigner.getWindowSerializer(getExecutionEnvironment().getConfig()),
keySel,
input.getKeyType().createSerializer(getExecutionEnvironment().getConfig()),
stateDesc,
new InternalIterableProcessWindowFunction<>(new FoldApplyProcessWindowFunction<>(initialValue, foldFunction, windowFunction, foldResultType)),
trigger,
evictor,
allowedLateness,
lateDataOutputTag);
} else {
FoldingStateDescriptor stateDesc = new FoldingStateDescriptor<>("window-contents",
initialValue,
foldFunction,
foldResultType.createSerializer(getExecutionEnvironment().getConfig()));
operator =
new WindowOperator<>(windowAssigner,
windowAssigner.getWindowSerializer(getExecutionEnvironment().getConfig()),
keySel,
input.getKeyType().createSerializer(getExecutionEnvironment().getConfig()),
stateDesc,
new InternalSingleValueProcessWindowFunction<>(windowFunction),
trigger,
allowedLateness,
lateDataOutputTag);
}
return input.transform(opName, windowResultType, operator);
}
// ------------------------------------------------------------------------
// Aggregation Function
// ------------------------------------------------------------------------
/**
* Applies the given aggregation function to each window. The aggregation function is called for
* each element, aggregating values incrementally and keeping the state to one accumulator
* per key and window.
*
* @param function The aggregation function.
* @return The data stream that is the result of applying the fold function to the window.
*
* @param The type of the AggregateFunction's accumulator
* @param The type of the elements in the resulting stream, equal to the
* AggregateFunction's result type
*/
@PublicEvolving
public SingleOutputStreamOperator aggregate(AggregateFunction function) {
checkNotNull(function, "function");
if (function instanceof RichFunction) {
throw new UnsupportedOperationException("This aggregation function cannot be a RichFunction.");
}
TypeInformation accumulatorType = TypeExtractor.getAggregateFunctionAccumulatorType(
function, input.getType(), null, false);
TypeInformation resultType = TypeExtractor.getAggregateFunctionReturnType(
function, input.getType(), null, false);
return aggregate(function, accumulatorType, resultType);
}
/**
* Applies the given aggregation function to each window. The aggregation function is called for
* each element, aggregating values incrementally and keeping the state to one accumulator
* per key and window.
*
* @param function The aggregation function.
* @return The data stream that is the result of applying the aggregation function to the window.
*
* @param The type of the AggregateFunction's accumulator
* @param The type of the elements in the resulting stream, equal to the
* AggregateFunction's result type
*/
@PublicEvolving
public SingleOutputStreamOperator aggregate(
AggregateFunction function,
TypeInformation accumulatorType,
TypeInformation resultType) {
checkNotNull(function, "function");
checkNotNull(accumulatorType, "accumulatorType");
checkNotNull(resultType, "resultType");
if (function instanceof RichFunction) {
throw new UnsupportedOperationException("This aggregation function cannot be a RichFunction.");
}
return aggregate(function, new PassThroughWindowFunction(),
accumulatorType, resultType, resultType);
}
/**
* Applies the given window function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the window function is
* interpreted as a regular non-windowed stream.
*
* Arriving data is incrementally aggregated using the given aggregate function. This means
* that the window function typically has only a single value to process when called.
*
* @param aggFunction The aggregate function that is used for incremental aggregation.
* @param windowFunction The window function.
*
* @return The data stream that is the result of applying the window function to the window.
*
* @param The type of the AggregateFunction's accumulator
* @param The type of AggregateFunction's result, and the WindowFunction's input
* @param The type of the elements in the resulting stream, equal to the
* WindowFunction's result type
*/
@PublicEvolving
public SingleOutputStreamOperator aggregate(
AggregateFunction aggFunction,
WindowFunction windowFunction) {
checkNotNull(aggFunction, "aggFunction");
checkNotNull(windowFunction, "windowFunction");
TypeInformation accumulatorType = TypeExtractor.getAggregateFunctionAccumulatorType(
aggFunction, input.getType(), null, false);
TypeInformation aggResultType = TypeExtractor.getAggregateFunctionReturnType(
aggFunction, input.getType(), null, false);
TypeInformation resultType = getWindowFunctionReturnType(windowFunction, aggResultType);
return aggregate(aggFunction, windowFunction, accumulatorType, aggResultType, resultType);
}
/**
* Applies the given window function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the window function is
* interpreted as a regular non-windowed stream.
*
* Arriving data is incrementally aggregated using the given aggregate function. This means
* that the window function typically has only a single value to process when called.
*
* @param aggregateFunction The aggregation function that is used for incremental aggregation.
* @param windowFunction The window function.
* @param accumulatorType Type information for the internal accumulator type of the aggregation function
* @param resultType Type information for the result type of the window function
*
* @return The data stream that is the result of applying the window function to the window.
*
* @param The type of the AggregateFunction's accumulator
* @param The type of AggregateFunction's result, and the WindowFunction's input
* @param The type of the elements in the resulting stream, equal to the
* WindowFunction's result type
*/
@PublicEvolving
public SingleOutputStreamOperator aggregate(
AggregateFunction aggregateFunction,
WindowFunction windowFunction,
TypeInformation accumulatorType,
TypeInformation aggregateResultType,
TypeInformation resultType) {
checkNotNull(aggregateFunction, "aggregateFunction");
checkNotNull(windowFunction, "windowFunction");
checkNotNull(accumulatorType, "accumulatorType");
checkNotNull(aggregateResultType, "aggregateResultType");
checkNotNull(resultType, "resultType");
if (aggregateFunction instanceof RichFunction) {
throw new UnsupportedOperationException("This aggregate function cannot be a RichFunction.");
}
//clean the closures
windowFunction = input.getExecutionEnvironment().clean(windowFunction);
aggregateFunction = input.getExecutionEnvironment().clean(aggregateFunction);
final String opName = generateOperatorName(windowAssigner, trigger, evictor, aggregateFunction, windowFunction);
KeySelector keySel = input.getKeySelector();
OneInputStreamOperator operator;
if (evictor != null) {
@SuppressWarnings({"unchecked", "rawtypes"})
TypeSerializer> streamRecordSerializer =
(TypeSerializer>) new StreamElementSerializer(input.getType().createSerializer(getExecutionEnvironment().getConfig()));
ListStateDescriptor> stateDesc =
new ListStateDescriptor<>("window-contents", streamRecordSerializer);
operator = new EvictingWindowOperator<>(windowAssigner,
windowAssigner.getWindowSerializer(getExecutionEnvironment().getConfig()),
keySel,
input.getKeyType().createSerializer(getExecutionEnvironment().getConfig()),
stateDesc,
new InternalIterableWindowFunction<>(new AggregateApplyWindowFunction<>(aggregateFunction, windowFunction)),
trigger,
evictor,
allowedLateness,
lateDataOutputTag);
} else {
AggregatingStateDescriptor stateDesc = new AggregatingStateDescriptor<>("window-contents",
aggregateFunction, accumulatorType.createSerializer(getExecutionEnvironment().getConfig()));
operator = new WindowOperator<>(windowAssigner,
windowAssigner.getWindowSerializer(getExecutionEnvironment().getConfig()),
keySel,
input.getKeyType().createSerializer(getExecutionEnvironment().getConfig()),
stateDesc,
new InternalSingleValueWindowFunction<>(windowFunction),
trigger,
allowedLateness,
lateDataOutputTag);
}
return input.transform(opName, resultType, operator);
}
/**
* Applies the given window function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the window function is
* interpreted as a regular non-windowed stream.
*
* Arriving data is incrementally aggregated using the given aggregate function. This means
* that the window function typically has only a single value to process when called.
*
* @param aggFunction The aggregate function that is used for incremental aggregation.
* @param windowFunction The window function.
*
* @return The data stream that is the result of applying the window function to the window.
*
* @param The type of the AggregateFunction's accumulator
* @param The type of AggregateFunction's result, and the WindowFunction's input
* @param The type of the elements in the resulting stream, equal to the
* WindowFunction's result type
*/
@PublicEvolving
public SingleOutputStreamOperator aggregate(
AggregateFunction aggFunction,
ProcessWindowFunction windowFunction) {
checkNotNull(aggFunction, "aggFunction");
checkNotNull(windowFunction, "windowFunction");
TypeInformation accumulatorType = TypeExtractor.getAggregateFunctionAccumulatorType(
aggFunction, input.getType(), null, false);
TypeInformation aggResultType = TypeExtractor.getAggregateFunctionReturnType(
aggFunction, input.getType(), null, false);
TypeInformation resultType = getProcessWindowFunctionReturnType(windowFunction, aggResultType, null);
return aggregate(aggFunction, windowFunction, accumulatorType, aggResultType, resultType);
}
private static TypeInformation getWindowFunctionReturnType(
WindowFunction function,
TypeInformation inType) {
return TypeExtractor.getUnaryOperatorReturnType(
function,
WindowFunction.class,
0,
1,
new int[]{2, 0},
new int[]{3, 0},
inType,
null,
false);
}
private static TypeInformation getProcessWindowFunctionReturnType(
ProcessWindowFunction function,
TypeInformation inType,
String functionName) {
return TypeExtractor.getUnaryOperatorReturnType(
function,
ProcessWindowFunction.class,
0,
1,
TypeExtractor.NO_INDEX,
TypeExtractor.NO_INDEX,
inType,
functionName,
false);
}
/**
* Applies the given window function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the window function is
* interpreted as a regular non-windowed stream.
*
* Arriving data is incrementally aggregated using the given aggregate function. This means
* that the window function typically has only a single value to process when called.
*
* @param aggregateFunction The aggregation function that is used for incremental aggregation.
* @param windowFunction The window function.
* @param accumulatorType Type information for the internal accumulator type of the aggregation function
* @param resultType Type information for the result type of the window function
*
* @return The data stream that is the result of applying the window function to the window.
*
* @param The type of the AggregateFunction's accumulator
* @param The type of AggregateFunction's result, and the WindowFunction's input
* @param The type of the elements in the resulting stream, equal to the
* WindowFunction's result type
*/
@PublicEvolving
public SingleOutputStreamOperator aggregate(
AggregateFunction aggregateFunction,
ProcessWindowFunction windowFunction,
TypeInformation accumulatorType,
TypeInformation aggregateResultType,
TypeInformation resultType) {
checkNotNull(aggregateFunction, "aggregateFunction");
checkNotNull(windowFunction, "windowFunction");
checkNotNull(accumulatorType, "accumulatorType");
checkNotNull(aggregateResultType, "aggregateResultType");
checkNotNull(resultType, "resultType");
if (aggregateFunction instanceof RichFunction) {
throw new UnsupportedOperationException("This aggregate function cannot be a RichFunction.");
}
//clean the closures
windowFunction = input.getExecutionEnvironment().clean(windowFunction);
aggregateFunction = input.getExecutionEnvironment().clean(aggregateFunction);
final String opName = generateOperatorName(windowAssigner, trigger, evictor, aggregateFunction, windowFunction);
KeySelector keySel = input.getKeySelector();
OneInputStreamOperator operator;
if (evictor != null) {
@SuppressWarnings({"unchecked", "rawtypes"})
TypeSerializer> streamRecordSerializer =
(TypeSerializer>) new StreamElementSerializer(input.getType().createSerializer(getExecutionEnvironment().getConfig()));
ListStateDescriptor> stateDesc =
new ListStateDescriptor<>("window-contents", streamRecordSerializer);
operator = new EvictingWindowOperator<>(windowAssigner,
windowAssigner.getWindowSerializer(getExecutionEnvironment().getConfig()),
keySel,
input.getKeyType().createSerializer(getExecutionEnvironment().getConfig()),
stateDesc,
new InternalAggregateProcessWindowFunction<>(aggregateFunction, windowFunction),
trigger,
evictor,
allowedLateness,
lateDataOutputTag);
} else {
AggregatingStateDescriptor stateDesc = new AggregatingStateDescriptor<>("window-contents",
aggregateFunction, accumulatorType.createSerializer(getExecutionEnvironment().getConfig()));
operator = new WindowOperator<>(windowAssigner,
windowAssigner.getWindowSerializer(getExecutionEnvironment().getConfig()),
keySel,
input.getKeyType().createSerializer(getExecutionEnvironment().getConfig()),
stateDesc,
new InternalSingleValueProcessWindowFunction<>(windowFunction),
trigger,
allowedLateness,
lateDataOutputTag);
}
return input.transform(opName, resultType, operator);
}
// ------------------------------------------------------------------------
// Window Function (apply)
// ------------------------------------------------------------------------
/**
* Applies the given window function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the window function is
* interpreted as a regular non-windowed stream.
*
* Not that this function requires that all data in the windows is buffered until the window
* is evaluated, as the function provides no means of incremental aggregation.
*
* @param function The window function.
* @return The data stream that is the result of applying the window function to the window.
*/
public SingleOutputStreamOperator apply(WindowFunction function) {
TypeInformation resultType = getWindowFunctionReturnType(function, getInputType());
return apply(function, resultType);
}
/**
* Applies the given window function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the window function is
* interpreted as a regular non-windowed stream.
*
* Note that this function requires that all data in the windows is buffered until the window
* is evaluated, as the function provides no means of incremental aggregation.
*
* @param function The window function.
* @param resultType Type information for the result type of the window function
* @return The data stream that is the result of applying the window function to the window.
*/
public SingleOutputStreamOperator apply(WindowFunction function, TypeInformation resultType) {
function = input.getExecutionEnvironment().clean(function);
return apply(new InternalIterableWindowFunction<>(function), resultType, function);
}
/**
* Applies the given window function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the window function is
* interpreted as a regular non-windowed stream.
*
* Not that this function requires that all data in the windows is buffered until the window
* is evaluated, as the function provides no means of incremental aggregation.
*
* @param function The window function.
* @return The data stream that is the result of applying the window function to the window.
*/
@PublicEvolving
public SingleOutputStreamOperator process(ProcessWindowFunction function) {
TypeInformation resultType = getProcessWindowFunctionReturnType(function, getInputType(), null);
return process(function, resultType);
}
/**
* Applies the given window function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the window function is
* interpreted as a regular non-windowed stream.
*
* Not that this function requires that all data in the windows is buffered until the window
* is evaluated, as the function provides no means of incremental aggregation.
*
* @param function The window function.
* @param resultType Type information for the result type of the window function
* @return The data stream that is the result of applying the window function to the window.
*/
@Internal
public SingleOutputStreamOperator process(ProcessWindowFunction function, TypeInformation resultType) {
function = input.getExecutionEnvironment().clean(function);
return apply(new InternalIterableProcessWindowFunction<>(function), resultType, function);
}
private SingleOutputStreamOperator apply(InternalWindowFunction, R, K, W> function, TypeInformation resultType, Function originalFunction) {
final String opName = generateOperatorName(windowAssigner, trigger, evictor, originalFunction, null);
KeySelector keySel = input.getKeySelector();
WindowOperator, R, W> operator;
if (evictor != null) {
@SuppressWarnings({"unchecked", "rawtypes"})
TypeSerializer> streamRecordSerializer =
(TypeSerializer>) new StreamElementSerializer(input.getType().createSerializer(getExecutionEnvironment().getConfig()));
ListStateDescriptor> stateDesc =
new ListStateDescriptor<>("window-contents", streamRecordSerializer);
operator =
new EvictingWindowOperator<>(windowAssigner,
windowAssigner.getWindowSerializer(getExecutionEnvironment().getConfig()),
keySel,
input.getKeyType().createSerializer(getExecutionEnvironment().getConfig()),
stateDesc,
function,
trigger,
evictor,
allowedLateness,
lateDataOutputTag);
} else {
ListStateDescriptor stateDesc = new ListStateDescriptor<>("window-contents",
input.getType().createSerializer(getExecutionEnvironment().getConfig()));
operator =
new WindowOperator<>(windowAssigner,
windowAssigner.getWindowSerializer(getExecutionEnvironment().getConfig()),
keySel,
input.getKeyType().createSerializer(getExecutionEnvironment().getConfig()),
stateDesc,
function,
trigger,
allowedLateness,
lateDataOutputTag);
}
return input.transform(opName, resultType, operator);
}
/**
* Applies the given window function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the window function is
* interpreted as a regular non-windowed stream.
*
* Arriving data is incrementally aggregated using the given reducer.
*
* @param reduceFunction The reduce function that is used for incremental aggregation.
* @param function The window function.
* @return The data stream that is the result of applying the window function to the window.
*
* @deprecated Use {@link #reduce(ReduceFunction, WindowFunction)} instead.
*/
@Deprecated
public SingleOutputStreamOperator apply(ReduceFunction reduceFunction, WindowFunction function) {
TypeInformation inType = input.getType();
TypeInformation resultType = getWindowFunctionReturnType(function, inType);
return apply(reduceFunction, function, resultType);
}
/**
* Applies the given window function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the window function is
* interpreted as a regular non-windowed stream.
*
* Arriving data is incrementally aggregated using the given reducer.
*
* @param reduceFunction The reduce function that is used for incremental aggregation.
* @param function The window function.
* @param resultType Type information for the result type of the window function
* @return The data stream that is the result of applying the window function to the window.
*
* @deprecated Use {@link #reduce(ReduceFunction, WindowFunction, TypeInformation)} instead.
*/
@Deprecated
public SingleOutputStreamOperator apply(ReduceFunction reduceFunction, WindowFunction function, TypeInformation resultType) {
if (reduceFunction instanceof RichFunction) {
throw new UnsupportedOperationException("ReduceFunction of apply can not be a RichFunction.");
}
//clean the closures
function = input.getExecutionEnvironment().clean(function);
reduceFunction = input.getExecutionEnvironment().clean(reduceFunction);
final String opName = generateOperatorName(windowAssigner, trigger, evictor, reduceFunction, function);
KeySelector keySel = input.getKeySelector();
OneInputStreamOperator operator;
if (evictor != null) {
@SuppressWarnings({"unchecked", "rawtypes"})
TypeSerializer> streamRecordSerializer =
(TypeSerializer>) new StreamElementSerializer(input.getType().createSerializer(getExecutionEnvironment().getConfig()));
ListStateDescriptor> stateDesc =
new ListStateDescriptor<>("window-contents", streamRecordSerializer);
operator =
new EvictingWindowOperator<>(windowAssigner,
windowAssigner.getWindowSerializer(getExecutionEnvironment().getConfig()),
keySel,
input.getKeyType().createSerializer(getExecutionEnvironment().getConfig()),
stateDesc,
new InternalIterableWindowFunction<>(new ReduceApplyWindowFunction<>(reduceFunction, function)),
trigger,
evictor,
allowedLateness,
lateDataOutputTag);
} else {
ReducingStateDescriptor stateDesc = new ReducingStateDescriptor<>("window-contents",
reduceFunction,
input.getType().createSerializer(getExecutionEnvironment().getConfig()));
operator =
new WindowOperator<>(windowAssigner,
windowAssigner.getWindowSerializer(getExecutionEnvironment().getConfig()),
keySel,
input.getKeyType().createSerializer(getExecutionEnvironment().getConfig()),
stateDesc,
new InternalSingleValueWindowFunction<>(function),
trigger,
allowedLateness,
lateDataOutputTag);
}
return input.transform(opName, resultType, operator);
}
/**
* Applies the given window function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the window function is
* interpreted as a regular non-windowed stream.
*
* Arriving data is incrementally aggregated using the given fold function.
*
* @param initialValue The initial value of the fold.
* @param foldFunction The fold function that is used for incremental aggregation.
* @param function The window function.
* @return The data stream that is the result of applying the window function to the window.
*
* @deprecated Use {@link #fold(Object, FoldFunction, WindowFunction)} instead.
*/
@Deprecated
public SingleOutputStreamOperator apply(R initialValue, FoldFunction foldFunction, WindowFunction function) {
TypeInformation resultType = TypeExtractor.getFoldReturnTypes(foldFunction, input.getType(),
Utils.getCallLocationName(), true);
return apply(initialValue, foldFunction, function, resultType);
}
/**
* Applies the given window function to each window. The window function is called for each
* evaluation of the window for each key individually. The output of the window function is
* interpreted as a regular non-windowed stream.
*
* Arriving data is incrementally aggregated using the given fold function.
*
* @param initialValue The initial value of the fold.
* @param foldFunction The fold function that is used for incremental aggregation.
* @param function The window function.
* @param resultType Type information for the result type of the window function
* @return The data stream that is the result of applying the window function to the window.
*
* @deprecated Use {@link #fold(Object, FoldFunction, WindowFunction, TypeInformation, TypeInformation)} instead.
*/
@Deprecated
public SingleOutputStreamOperator apply(R initialValue, FoldFunction foldFunction, WindowFunction function, TypeInformation resultType) {
if (foldFunction instanceof RichFunction) {
throw new UnsupportedOperationException("FoldFunction of apply can not be a RichFunction.");
}
if (windowAssigner instanceof MergingWindowAssigner) {
throw new UnsupportedOperationException("Fold cannot be used with a merging WindowAssigner.");
}
//clean the closures
function = input.getExecutionEnvironment().clean(function);
foldFunction = input.getExecutionEnvironment().clean(foldFunction);
final String opName = generateOperatorName(windowAssigner, trigger, evictor, foldFunction, function);
KeySelector keySel = input.getKeySelector();
OneInputStreamOperator operator;
if (evictor != null) {
@SuppressWarnings({"unchecked", "rawtypes"})
TypeSerializer> streamRecordSerializer =
(TypeSerializer>) new StreamElementSerializer(input.getType().createSerializer(getExecutionEnvironment().getConfig()));
ListStateDescriptor