Package org.apache.wayang.basic.operators

Class RepeatOperator<Type>

java.lang.Object

org.apache.wayang.core.plan.wayangplan.OperatorBase

org.apache.wayang.basic.operators.RepeatOperator<Type>

All Implemented Interfaces:

Serializable, ActualOperator, ElementaryOperator, LoopHeadOperator, Operator

Direct Known Subclasses:

FlinkRepeatExpandedOperator, FlinkRepeatOperator, JavaRepeatOperator, SparkRepeatOperator

public class RepeatOperator<Type>
extends OperatorBase
implements ElementaryOperator, LoopHeadOperator

This Operator repeats a certain subplan of Operators for a given number of times.

See Also:

• Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.wayang.core.plan.wayangplan.OperatorBase

OperatorBase.GsonSerializer

Nested classes/interfaces inherited from interface org.apache.wayang.core.plan.wayangplan.LoopHeadOperator

LoopHeadOperator.State

Field Summary

Fields

Modifier and Type	Field	Description
static final int	FINAL_OUTPUT_INDEX
static final int	INITIAL_INPUT_INDEX
static final int	ITERATION_INPUT_INDEX
static final int	ITERATION_OUTPUT_INDEX

Fields inherited from class org.apache.wayang.core.plan.wayangplan.OperatorBase

inputSlots, outputSlots, STANDARD_OPERATOR_ARGS

Fields inherited from interface org.apache.wayang.core.plan.wayangplan.Operator

FIRST_EPOCH

Constructor Summary

Constructors

Constructor	Description
RepeatOperator(Integer numIterations, Class<Type> typeClass)	Creates a new instance.
RepeatOperator(Integer numIterations, DataSetType<Type> type)	Creates a new instance.
RepeatOperator(RepeatOperator<Type> that)	Creates a copy of the given RepeatOperator.

Method Summary

Modifier and Type	Method	Description
void	beginIteration(Operator beginOperator, int beginInputIndex)
void	connectFinalOutputTo(Operator outputOperator, int thatInputIndex)
Optional<CardinalityEstimator>	createCardinalityEstimator(int outputIndex, Configuration configuration)	Provide a CardinalityEstimator for the OutputSlot at outputIndex.
void	endIteration(Operator endOperator, int endOpOutputIndex)
Collection<InputSlot<?>>	getConditionInputSlots()	Retrieve those InputSlots that are required to evaluate the loop condition.
Collection<OutputSlot<?>>	getConditionOutputSlots()	Retrieve those OutputSlots that forward the LoopHeadOperator.getConditionInputSlots().
Collection<OutputSlot<?>>	getFinalLoopOutputs()	If this instance is the head of a loop, then return these OutputSlots that form the final result of the iteration.
Collection<OutputSlot<?>>	getForwards(InputSlot<?> input)	Declare forward rules.
Collection<InputSlot<?>>	getLoopBodyInputs()	If this instance is the head of a loop, then return these InputSlots that are fed from the loop body (as opposed to the InputSlots that initialize the loop).
Collection<OutputSlot<?>>	getLoopBodyOutputs()	If this instance is the head of a loop, then return these OutputSlots that go into the loop body (as opposed to the OutputSlots that form the final result of the iteration).
Collection<InputSlot<?>>	getLoopInitializationInputs()	If this instance is the head of a loop, then return these InputSlots that initialize the loop.
int	getNumExpectedIterations()
int	getNumIterations()
LoopHeadOperator.State	getState()	Optional operation.
DataSetType<Type>	getType()
void	initialize(Operator initOperator, int initOpOutputIndex)
boolean	isReading(InputSlot<?> input)	Tells whether the given input is read by this operator.
void	setState(LoopHeadOperator.State state)	Optional operation.

Methods inherited from class org.apache.wayang.core.plan.wayangplan.OperatorBase

accept, addBroadcastInput, addTargetPlatform, at, collectMappedInputSlots, collectMappedOutputSlots, copy, createCopy, getAllInputs, getAllOutputs, getCardinalityEstimator, getContainer, getEpoch, getName, getOriginal, getSimpleClassName, getTargetPlatforms, isAuxiliary, isSupportingBroadcastInputs, propagateInputCardinality, propagateOutputCardinality, setAuxiliary, setCardinalityEstimator, setContainer, setEpoch, setName, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.wayang.core.plan.wayangplan.ActualOperator

accept

Methods inherited from interface org.apache.wayang.core.plan.wayangplan.ElementaryOperator

getCardinalityEstimator, isAuxiliary, setAuxiliary, setCardinalityEstimator

Methods inherited from interface org.apache.wayang.core.plan.wayangplan.LoopHeadOperator

getCardinalityPusher, getFinalizationPusher, getInitializationPusher

Methods inherited from interface org.apache.wayang.core.plan.wayangplan.Operator

addBroadcastInput, addTargetPlatform, broadcastTo, broadcastTo, collectMappedInputSlots, collectMappedOutputSlots, connectTo, connectTo, getAllInputs, getAllOutputs, getContainer, getEffectiveOccupant, getEffectiveOccupant, getEpoch, getEstimationContextProperties, getInnermostLoop, getInput, getInput, getLoopStack, getName, getNumBroadcastInputs, getNumInputs, getNumOutputs, getNumRegularInputs, getOuterInputSlot, getOutermostInputSlot, getOutermostOutputSlots, getOutput, getOutput, getParent, getTargetPlatforms, isAlternative, isConversion, isElementary, isExecutionOperator, isFeedbackInput, isFeedforwardOutput, isLoopHead, isLoopSubplan, isOwnerOf, isSink, isSource, isSubplan, isSupportingBroadcastInputs, isUnconnected, propagateInputCardinality, propagateOutputCardinality, propagateOutputCardinality, replaceWith, setContainer, setEpoch, setInput, setName, setOutput

Field Details

INITIAL_INPUT_INDEX

public static final int INITIAL_INPUT_INDEX

See Also:

• Constant Field Values

ITERATION_INPUT_INDEX

public static final int ITERATION_INPUT_INDEX

See Also:

• Constant Field Values

ITERATION_OUTPUT_INDEX

public static final int ITERATION_OUTPUT_INDEX

See Also:

• Constant Field Values

FINAL_OUTPUT_INDEX

public static final int FINAL_OUTPUT_INDEX

See Also:

• Constant Field Values

Constructor Details

RepeatOperator

public RepeatOperator(Integer numIterations,
 Class<Type> typeClass)

Creates a new instance.

Parameters:

numIterations - number of iterations to be performed

typeClass - of the "circulated" dataset

RepeatOperator

public RepeatOperator(Integer numIterations,
 DataSetType<Type> type)

Creates a new instance.

Parameters:

numIterations - number of iterations to be performed

type - of the "circulated" dataset

RepeatOperator

public RepeatOperator(RepeatOperator<Type> that)

Creates a copy of the given RepeatOperator.

Parameters:

that - should be copied

Method Details

getState

public LoopHeadOperator.State getState()

Description copied from interface: LoopHeadOperator

Optional operation. Only ExecutionOperators need to implement this method.

Specified by:

getState in interface LoopHeadOperator

Returns:

the current LoopHeadOperator.State of this instance

setState

public void setState(LoopHeadOperator.State state)

Description copied from interface: LoopHeadOperator

Optional operation. Only ExecutionOperators need to implement this method. Sets the LoopHeadOperator.State of this instance.

Specified by:

setState in interface LoopHeadOperator

getType

public DataSetType<Type> getType()

initialize

public void initialize(Operator initOperator,
 int initOpOutputIndex)

beginIteration

public void beginIteration(Operator beginOperator,
 int beginInputIndex)

endIteration

public void endIteration(Operator endOperator,
 int endOpOutputIndex)

connectFinalOutputTo

public void connectFinalOutputTo(Operator outputOperator,
 int thatInputIndex)

getForwards

public Collection<OutputSlot<?>> getForwards(InputSlot<?> input)

Description copied from interface: Operator

Declare forward rules. Execution engines may take the chance to optimize the executed plans by having forwarded data by-pass this instance. However, note the specific semantics of a forward rule: If an Operator serves an OutputSlot that is involved in a foward rule, it will do so by forwarding. If the OutputSlot is not served, then the forwarding does not apply.

Specified by:

getForwards in interface Operator

Returns:

OutputSlots to which this instance forwards the given input.

See Also:

• Operator.isReading(InputSlot)

isReading

public boolean isReading(InputSlot<?> input)

Description copied from interface: Operator

Tells whether the given input is read by this operator. If not, the optimizer can make use of this insight.

Specified by:

isReading in interface Operator

See Also:

• Operator.getForwards(InputSlot)

createCardinalityEstimator

public Optional<CardinalityEstimator> createCardinalityEstimator(int outputIndex,
 Configuration configuration)

Description copied from interface: ElementaryOperator

Provide a CardinalityEstimator for the OutputSlot at outputIndex.

Specified by:

createCardinalityEstimator in interface ElementaryOperator

Parameters:

outputIndex - index of the OutputSlot for that the CardinalityEstimator is requested

configuration - if the CardinalityEstimator depends on further ones, use this to obtain the latter

Returns:

an Optional that might provide the requested instance

getLoopBodyOutputs

public Collection<OutputSlot<?>> getLoopBodyOutputs()

Description copied from interface: LoopHeadOperator

If this instance is the head of a loop, then return these OutputSlots that go into the loop body (as opposed to the OutputSlots that form the final result of the iteration).

Specified by:

getLoopBodyOutputs in interface LoopHeadOperator

Returns:

the loop body-bound OutputSlots

getFinalLoopOutputs

public Collection<OutputSlot<?>> getFinalLoopOutputs()

Description copied from interface: LoopHeadOperator

If this instance is the head of a loop, then return these OutputSlots that form the final result of the iteration.

Specified by:

getFinalLoopOutputs in interface LoopHeadOperator

Returns:

the loop-terminal OutputSlots

getLoopBodyInputs

public Collection<InputSlot<?>> getLoopBodyInputs()

Description copied from interface: LoopHeadOperator

If this instance is the head of a loop, then return these InputSlots that are fed from the loop body (as opposed to the InputSlots that initialize the loop).

Specified by:

getLoopBodyInputs in interface LoopHeadOperator

Returns:

the loop body-bound InputSlots

getLoopInitializationInputs

public Collection<InputSlot<?>> getLoopInitializationInputs()

Description copied from interface: LoopHeadOperator

If this instance is the head of a loop, then return these InputSlots that initialize the loop.

Specified by:

getLoopInitializationInputs in interface LoopHeadOperator

Returns:

the initialization InputSlots

getConditionInputSlots

public Collection<InputSlot<?>> getConditionInputSlots()

Description copied from interface: LoopHeadOperator

Retrieve those InputSlots that are required to evaluate the loop condition.

Specified by:

getConditionInputSlots in interface LoopHeadOperator

Returns:

the condition InputSlots

getConditionOutputSlots

public Collection<OutputSlot<?>> getConditionOutputSlots()

Description copied from interface: LoopHeadOperator

Retrieve those OutputSlots that forward the LoopHeadOperator.getConditionInputSlots().

Specified by:

getConditionOutputSlots in interface LoopHeadOperator

Returns:

the condition OutputSlots

getNumIterations

public int getNumIterations()

getNumExpectedIterations

public int getNumExpectedIterations()

Specified by:

getNumExpectedIterations in interface LoopHeadOperator

Returns:

a number of expected iterations; not necessarily the actual value