org.apache.flink.api.java.record.operators

Class ReduceOperator

java.lang.Object

org.apache.flink.api.common.operators.Operator<OUT>

org.apache.flink.api.common.operators.AbstractUdfOperator<OUT,FT>

org.apache.flink.api.common.operators.SingleInputOperator<IN,OUT,FT>

org.apache.flink.api.common.operators.base.GroupReduceOperatorBase<org.apache.flink.types.Record,org.apache.flink.types.Record,org.apache.flink.api.common.functions.GroupReduceFunction<org.apache.flink.types.Record,org.apache.flink.types.Record>>

org.apache.flink.api.java.record.operators.ReduceOperator

All Implemented Interfaces:

org.apache.flink.api.common.operators.RecordOperator, org.apache.flink.util.Visitable<org.apache.flink.api.common.operators.Operator<?>>

public class ReduceOperator
extends org.apache.flink.api.common.operators.base.GroupReduceOperatorBase<org.apache.flink.types.Record,org.apache.flink.types.Record,org.apache.flink.api.common.functions.GroupReduceFunction<org.apache.flink.types.Record,org.apache.flink.types.Record>>
implements org.apache.flink.api.common.operators.RecordOperator

ReduceOperator evaluating a ReduceFunction over each group of records that share the same key.

See Also:

ReduceFunction

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ReduceOperator.Builder Builder pattern, straight from Joshua Bloch's Effective Java (2nd Edition).
static interface	ReduceOperator.Combinable This annotation marks reduce stubs as eligible for the usage of a combiner.
static class	ReduceOperator.WrappingClassReduceFunction
static class	ReduceOperator.WrappingReduceFunction

Field Summary

Fields inherited from class org.apache.flink.api.common.operators.SingleInputOperator

input

Fields inherited from class org.apache.flink.api.common.operators.AbstractUdfOperator

broadcastInputs, userFunction

Fields inherited from class org.apache.flink.api.common.operators.Operator

compilerHints, name, operatorInfo, parameters

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	ReduceOperator(ReduceOperator.Builder builder) The private constructor that only gets invoked from the Builder.

Method Summary

Modifier and Type	Method and Description
static ReduceOperator.Builder	builder(Class<? extends ReduceFunction> udf) Creates a Builder with the provided ReduceFunction implementation.
static ReduceOperator.Builder	builder(Class<? extends ReduceFunction> udf, Class<? extends org.apache.flink.types.Key<?>> keyClass, int keyColumn) Creates a Builder with the provided ReduceFunction implementation.
static ReduceOperator.Builder	builder(ReduceFunction udf) Creates a Builder with the provided ReduceFunction implementation.
static ReduceOperator.Builder	builder(ReduceFunction udf, Class<? extends org.apache.flink.types.Key<?>> keyClass, int keyColumn) Creates a Builder with the provided ReduceFunction implementation.
Class<? extends org.apache.flink.types.Key<?>>[]	getKeyClasses()
boolean	isCombinable()

Methods inherited from class org.apache.flink.api.common.operators.base.GroupReduceOperatorBase

executeOnCollections, getCustomPartitioner, getGroupOrder, setCombinable, setCustomPartitioner, setGroupOrder

Methods inherited from class org.apache.flink.api.common.operators.SingleInputOperator

accept, addInput, addInput, clearInputs, getInput, getKeyColumns, getNumberOfInputs, getOperatorInfo, getSemanticProperties, setInput, setInput, setInputs, setSemanticProperties

Methods inherited from class org.apache.flink.api.common.operators.AbstractUdfOperator

asArray, emptyClassArray, getBroadcastInputs, getUserCodeWrapper, setBroadcastVariable, setBroadcastVariables

Methods inherited from class org.apache.flink.api.common.operators.Operator

createUnionCascade, createUnionCascade, createUnionCascade, getCompilerHints, getDegreeOfParallelism, getName, getParallelism, getParameters, setDegreeOfParallelism, setName, setParallelism, setParameter, setParameter, setParameter, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

ReduceOperator

protected ReduceOperator(ReduceOperator.Builder builder)

The private constructor that only gets invoked from the Builder.

Parameters:

builder -

Method Detail

builder

public static ReduceOperator.Builder builder(ReduceFunction udf)

Creates a Builder with the provided ReduceFunction implementation.

Parameters:

udf - The ReduceFunction implementation for this Reduce contract.

builder

public static ReduceOperator.Builder builder(ReduceFunction udf,
                                             Class<? extends org.apache.flink.types.Key<?>> keyClass,
                                             int keyColumn)

Creates a Builder with the provided ReduceFunction implementation.

Parameters:

udf - The ReduceFunction implementation for this Reduce contract.

keyClass - The class of the key data type.

keyColumn - The position of the key.

builder

public static ReduceOperator.Builder builder(Class<? extends ReduceFunction> udf)

Creates a Builder with the provided ReduceFunction implementation.

Parameters:

udf - The ReduceFunction implementation for this Reduce contract.

builder

public static ReduceOperator.Builder builder(Class<? extends ReduceFunction> udf,
                                             Class<? extends org.apache.flink.types.Key<?>> keyClass,
                                             int keyColumn)

Creates a Builder with the provided ReduceFunction implementation.

Parameters:

udf - The ReduceFunction implementation for this Reduce contract.

keyClass - The class of the key data type.

keyColumn - The position of the key.

getKeyClasses

public Class<? extends org.apache.flink.types.Key<?>>[] getKeyClasses()

Specified by:

getKeyClasses in interface org.apache.flink.api.common.operators.RecordOperator

isCombinable

public boolean isCombinable()

Overrides:

isCombinable in class org.apache.flink.api.common.operators.base.GroupReduceOperatorBase<org.apache.flink.types.Record,org.apache.flink.types.Record,org.apache.flink.api.common.functions.GroupReduceFunction<org.apache.flink.types.Record,org.apache.flink.types.Record>>