Package org.apache.wayang.core.optimizer

Class OptimizationContext.LoopContext

java.lang.Object

org.apache.wayang.core.optimizer.OptimizationContext.LoopContext

Enclosing class:

OptimizationContext

public class OptimizationContext.LoopContext
extends Object

Maintains OptimizationContexts for the iterations of a LoopSubplan.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	LoopContext(OptimizationContext.OperatorContext loopSubplanContext)

Method Summary

Modifier and Type	Method	Description
OptimizationContext	appendIterationContext()	Add a new iteration OptimizationContext between second-to-last and final iteration.
AggregateOptimizationContext	getAggregateContext()
OptimizationContext	getFinalIterationContext()
OptimizationContext	getInitialIterationContext()
OptimizationContext	getIterationContext(int iteration)
List<OptimizationContext>	getIterationContexts()	Retrieves the iteration OptimizationContexts.
LoopSubplan	getLoop()
OptimizationContext.OperatorContext	getLoopSubplanContext()
OptimizationContext	getOptimizationContext()

Methods inherited from class java.lang.Object

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

Constructor Details

LoopContext

protected LoopContext(OptimizationContext.OperatorContext loopSubplanContext)

Method Details

getLoopSubplanContext

public OptimizationContext.OperatorContext getLoopSubplanContext()

getIterationContexts

public List<OptimizationContext> getIterationContexts()

Retrieves the iteration OptimizationContexts.

Note that for n iterations, there are n+1 OptimizationContexts because the LoopHeadOperator is triggered n+1 times. The first n represent the iterations, the final represents the final state of the loop, in which only the LoopHeadOperator is run the last time.

Returns:

the OptimizationContext for each iteration; order by execution order

getIterationContext

public OptimizationContext getIterationContext(int iteration)

getOptimizationContext

public OptimizationContext getOptimizationContext()

Returns:

the OptimizationContext in that the LoopSubplan resides

getInitialIterationContext

public OptimizationContext getInitialIterationContext()

getFinalIterationContext

public OptimizationContext getFinalIterationContext()

appendIterationContext

public OptimizationContext appendIterationContext()

Add a new iteration OptimizationContext between second-to-last and final iteration.

Returns:

the added OptimizationContext

getLoop

public LoopSubplan getLoop()

getAggregateContext

public AggregateOptimizationContext getAggregateContext()