Package org.rumbledb.runtime.flwor.clauses

Class WindowClauseIterator

java.lang.Object

org.rumbledb.runtime.plan.RuntimePlan<FlworTuple>

org.rumbledb.runtime.TupleRuntimePlan

org.rumbledb.runtime.flwor.clauses.WindowClauseIterator

All Implemented Interfaces:

Serializable, LocalRuntimePlan<FlworTuple>, NativeQueryRuntimePlan

public class WindowClauseIterator
extends TupleRuntimePlan

See Also:

• Serialized Form

Field Summary

Fields inherited from class org.rumbledb.runtime.TupleRuntimePlan

child, evaluationDepthLimit, inputTupleProjection, outputTupleProjection

Fields inherited from class org.rumbledb.runtime.plan.RuntimePlan

staticContext

Constructor Summary

Constructors

Constructor	Description
WindowClauseIterator(TupleRuntimePlan child, WindowClause clause, ItemRuntimePlan sourceIterator, ItemRuntimePlan startCondition, ItemRuntimePlan endCondition, RuntimeStaticContext staticContext)

Method Summary

Modifier and Type	Method	Description
boolean	containsClause(FLWOR_CLAUSES kind)	Says whether or not the clause and its descendants include a clause of the specified kind.
Cursor<FlworTuple>	createNativeCursor(DynamicContext context)	Creates an independent cursor for one native local evaluation.
Map<Name,DynamicContext.VariableDependency>	getDynamicContextVariableDependencies()	Variable dependencies are variables that MUST be provided by the parent clause in the dynamic context for successful execution of this clause.
protected Map<Name,DynamicContext.VariableDependency>	getInputTupleVariableDependencies(Map<Name,DynamicContext.VariableDependency> parentProjection)	Builds the DataFrame projection that this clause needs to receive from its child clause.
Set<Name>	getOutputTupleVariableNames()	Reports all variables available after the window clause
boolean	isSparkJobNeeded()	Says whether this expression evaluation triggers a Spark job.

Methods inherited from class org.rumbledb.runtime.TupleRuntimePlan

canSetEvaluationDepthLimit, generateNativeQuery, getChildIterator, getEvaluationDepthLimit, getHeight, getStaticContext, getSubtreeBeyondLimit, isDataFrame, print, setEvaluationDepthLimit, setInputAndOutputTupleVariableDependencies, toString

Methods inherited from class org.rumbledb.runtime.plan.RuntimePlan

getConfiguration, getCursor, getDataFrame, getMetadata, getRDD, getRuntimeStaticContext, materialize, materializeAtMost, materializeAtMostOne, materializeExactlyOne, materializeFirstOrNull

Methods inherited from class java.lang.Object

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

Constructor Details

WindowClauseIterator

public WindowClauseIterator(TupleRuntimePlan child,
 WindowClause clause,
 ItemRuntimePlan sourceIterator,
 ItemRuntimePlan startCondition,
 ItemRuntimePlan endCondition,
 RuntimeStaticContext staticContext)

Method Details

createNativeCursor

public Cursor<FlworTuple> createNativeCursor(DynamicContext context)

Description copied from interface: LocalRuntimePlan

Creates an independent cursor for one native local evaluation.

Specified by:

createNativeCursor in interface LocalRuntimePlan<FlworTuple>

Specified by:

createNativeCursor in class TupleRuntimePlan

Parameters:

context - the dynamic context for that evaluation

Returns:

an unopened cursor

getDynamicContextVariableDependencies

public Map<Name,DynamicContext.VariableDependency> getDynamicContextVariableDependencies()

Description copied from class: TupleRuntimePlan

Variable dependencies are variables that MUST be provided by the parent clause in the dynamic context for successful execution of this clause. These variables are: 1. All variables that the expression of the clause depends on (recursive call of getVariableDependencies on the expression) 2. Except those variables bound in the current FLWOR (obtained from the auxiliary method getVariablesBoundInCurrentFLWORExpression), because those are provided in the Tuples 3. Plus (recursively calling getVariableDependencies) all the Variable Dependencies of the child clause if it exists.

Overrides:

getDynamicContextVariableDependencies in class TupleRuntimePlan

Returns:

a map of variable names to dependencies (FULL, COUNT, ...) that this clause needs to obtain from the dynamic context.

getInputTupleVariableDependencies

protected Map<Name,DynamicContext.VariableDependency> getInputTupleVariableDependencies(Map<Name,DynamicContext.VariableDependency> parentProjection)

Description copied from class: TupleRuntimePlan

Builds the DataFrame projection that this clause needs to receive from its child clause. The intent is that the result of this method is forwarded to the child clause in getDataFrame() so it can optimize some values away. Invariant: all keys in getInputTupleVariableDependencies(...) MUST be output tuple variables, i.e., appear in this.child.getOutputTupleVariableNames()

Specified by:

getInputTupleVariableDependencies in class TupleRuntimePlan

Parameters:

parentProjection - the projection needed by the parent clause.

Returns:

the projection needed by this clause.

getOutputTupleVariableNames

public Set<Name> getOutputTupleVariableNames()

Reports all variables available after the window clause

Overrides:

getOutputTupleVariableNames in class TupleRuntimePlan

Returns:

the set of variable names that are bound by descendant clauses.

containsClause

public boolean containsClause(FLWOR_CLAUSES kind)

Description copied from class: TupleRuntimePlan

Says whether or not the clause and its descendants include a clause of the specified kind.

Specified by:

containsClause in class TupleRuntimePlan

Parameters:

kind - the kind of clause to test for.

Returns:

true if there is one. False otherwise.

isSparkJobNeeded

public boolean isSparkJobNeeded()

Description copied from class: TupleRuntimePlan

Says whether this expression evaluation triggers a Spark job.

Specified by:

isSparkJobNeeded in class TupleRuntimePlan

Returns:

true if the execution triggers a Spark, false otherwise, null if undetermined yet.