Package org.apache.wayang.core.optimizer

Class OptimizationContext

java.lang.Object

org.apache.wayang.core.optimizer.OptimizationContext

Direct Known Subclasses:

AggregateOptimizationContext, DefaultOptimizationContext

public abstract class OptimizationContext
extends Object

Manages contextual information required during the optimization of a WayangPlan.

A single Operator can have multiple contexts in a WayangPlan - namely if it appears in a loop. We manage these contexts in a hierarchical fashion.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
class	OptimizationContext.LoopContext	Maintains OptimizationContexts for the iterations of a LoopSubplan.
class	OptimizationContext.OperatorContext	Represents a single optimization context of an Operator.

Field Summary

Fields

Modifier and Type	Field	Description
protected final OptimizationContext.LoopContext	hostLoopContext	The instance in that this instance is nested - or null if it is top-level.
protected final Job	job	The Job whose WayangPlan is to be optimized.
protected final org.apache.logging.log4j.Logger	logger

Constructor Summary

Constructors

Modifier	Constructor	Description
	OptimizationContext(Job job)	Create a new, plain instance.
protected	OptimizationContext(Job job, OptimizationContext base, OptimizationContext.LoopContext hostLoopContext, int iterationNumber, ChannelConversionGraph channelConversionGraph, List<PlanEnumerationPruningStrategy> pruningStrategies)	Base constructor.
	OptimizationContext(Job job, Operator operator)	Creates a new instance.

Method Summary

Modifier and Type	Method	Description
abstract void	addOneTimeLoop(OptimizationContext.OperatorContext operatorContext)	Add OptimizationContexts for the loop that is executed once within this instance.
abstract OptimizationContext.OperatorContext	addOneTimeOperator(Operator operator)	Add OptimizationContext.OperatorContexts for the operator that is executed once within this instance.
void	addOneTimeOperators(OperatorContainer container)	Add OptimizationContext.OperatorContexts for all the contained Operators of the container.
abstract void	clearMarks()	Calls OptimizationContext.OperatorContext.clearMarks() for all nested OptimizationContext.OperatorContexts.
OptimizationContext	getBase()
ChannelConversionGraph	getChannelConversionGraph()
Configuration	getConfiguration()
abstract List<DefaultOptimizationContext>	getDefaultOptimizationContexts()	Get the DefaultOptimizationContexts represented by this instance.
int	getIterationNumber()
Job	getJob()	Provide the Job whose optimization is supported by this instance.
abstract Map<Operator,OptimizationContext.OperatorContext>	getLocalOperatorContexts()
OptimizationContext.LoopContext	getLoopContext()	Retrieve the OptimizationContext.LoopContext in which this instance resides.
abstract OptimizationContext.LoopContext	getNestedLoopContext(LoopSubplan loopSubplan)	Retrieve the OptimizationContext.LoopContext for the loopSubplan.
OptimizationContext	getNextIterationContext()
abstract OptimizationContext.OperatorContext	getOperatorContext(Operator operator)	Return the OptimizationContext.OperatorContext of the operator.
OptimizationContext	getParent()
List<PlanEnumerationPruningStrategy>	getPruningStrategies()
OptimizationContext	getRootParent()	Get the top-level parent containing this instance.
boolean	isFinalIteration()
boolean	isInitialIteration()
abstract boolean	isTimeEstimatesComplete()
abstract void	mergeToBase()
Object	putIntoJobCache(String key, Object value)	Stores a value into the Job-global cache.
Object	queryJobCache(String key)	Queries the Job-global cache.
<T> T	queryJobCache(String key, Class<T> resultClass)	Queries the Job-global cache.

Methods inherited from class java.lang.Object

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

Field Details

logger

protected final org.apache.logging.log4j.Logger logger

job

protected final Job job

The Job whose WayangPlan is to be optimized.

hostLoopContext

protected final OptimizationContext.LoopContext hostLoopContext

The instance in that this instance is nested - or null if it is top-level.

Constructor Details

OptimizationContext

public OptimizationContext(Job job)

Create a new, plain instance.

OptimizationContext

public OptimizationContext(Job job,
 Operator operator)

Creates a new instance. Useful for testing.

Parameters:

operator - the single Operator of this instance

OptimizationContext

protected OptimizationContext(Job job,
 OptimizationContext base,
 OptimizationContext.LoopContext hostLoopContext,
 int iterationNumber,
 ChannelConversionGraph channelConversionGraph,
 List<PlanEnumerationPruningStrategy> pruningStrategies)

Base constructor.

Method Details

addOneTimeOperator

public abstract OptimizationContext.OperatorContext addOneTimeOperator(Operator operator)

Add OptimizationContext.OperatorContexts for the operator that is executed once within this instance. Also add its encased Operators. Potentially invoke addOneTimeLoop(OperatorContext) as well.

addOneTimeOperators

public void addOneTimeOperators(OperatorContainer container)

Add OptimizationContext.OperatorContexts for all the contained Operators of the container.

addOneTimeLoop

public abstract void addOneTimeLoop(OptimizationContext.OperatorContext operatorContext)

Add OptimizationContexts for the loop that is executed once within this instance.

getOperatorContext

public abstract OptimizationContext.OperatorContext getOperatorContext(Operator operator)

Return the OptimizationContext.OperatorContext of the operator.

Parameters:

operator - a one-time Operator (i.e., not in a nested loop)

Returns:

the OptimizationContext.OperatorContext for the Operator or null if none

getNestedLoopContext

public abstract OptimizationContext.LoopContext getNestedLoopContext(LoopSubplan loopSubplan)

Retrieve the OptimizationContext.LoopContext for the loopSubplan.

getIterationNumber

public int getIterationNumber()

Returns:

if this instance describes an iteration within a LoopSubplan, return the number of that iteration (starting at 0); otherwise -1

isInitialIteration

public boolean isInitialIteration()

Returns:

whether this instance is the first iteration within a OptimizationContext.LoopContext; this instance must be embedded in a OptimizationContext.LoopContext

isFinalIteration

public boolean isFinalIteration()

Returns:

whether this instance is the final iteration within a OptimizationContext.LoopContext; this instance must be embedded in a OptimizationContext.LoopContext

getLoopContext

public OptimizationContext.LoopContext getLoopContext()

Retrieve the OptimizationContext.LoopContext in which this instance resides.

Returns:

the OptimizationContext.LoopContext or null if none

getParent

public OptimizationContext getParent()

Returns:

if this instance describes an iteration within a LoopSubplan, return the instance in which this instance is nested

getNextIterationContext

public OptimizationContext getNextIterationContext()

clearMarks

public abstract void clearMarks()

Calls OptimizationContext.OperatorContext.clearMarks() for all nested OptimizationContext.OperatorContexts.

getConfiguration

public Configuration getConfiguration()

getLocalOperatorContexts

public abstract Map<Operator,OptimizationContext.OperatorContext> getLocalOperatorContexts()

Returns:

the OptimizationContext.OperatorContexts of this instance (exclusive of any base instance)

isTimeEstimatesComplete

public abstract boolean isTimeEstimatesComplete()

Returns:

whether there is a TimeEstimate for each ExecutionOperator

getChannelConversionGraph

public ChannelConversionGraph getChannelConversionGraph()

getBase

public OptimizationContext getBase()

mergeToBase

public abstract void mergeToBase()

getPruningStrategies

public List<PlanEnumerationPruningStrategy> getPruningStrategies()

getRootParent

public OptimizationContext getRootParent()

Get the top-level parent containing this instance.

Returns:

the top-level parent, which can also be this instance

getDefaultOptimizationContexts

public abstract List<DefaultOptimizationContext> getDefaultOptimizationContexts()

Get the DefaultOptimizationContexts represented by this instance.

Returns:

a Collection of said DefaultOptimizationContexts

getJob

public Job getJob()

Provide the Job whose optimization is supported by this instance.

Returns:

the Job

putIntoJobCache

public Object putIntoJobCache(String key,
 Object value)

Stores a value into the Job-global cache.

Parameters:

key - identifies the value

value - the value

Returns:

the value previously associated with the key or else null

queryJobCache

public Object queryJobCache(String key)

Queries the Job-global cache.

Parameters:

key - that is associated with the value to be retrieved

Returns:

the value associated with the key or else null

queryJobCache

public <T> T queryJobCache(String key,
 Class<T> resultClass)

Queries the Job-global cache.

Parameters:

key - that is associated with the value to be retrieved

resultClass - the expected Class of the retrieved value

Returns:

the value associated with the key or else null