Class HashJoin

java.lang.Object

org.eclipse.rdf4j.common.iteration.AbstractCloseableIteration<BindingSet>

org.eclipse.rdf4j.common.iteration.LookAheadIteration<BindingSet>

org.eclipse.rdf4j.federated.evaluation.concurrent.ParallelExecutorBase<BindingSet>

org.eclipse.rdf4j.federated.evaluation.join.JoinExecutorBase<BindingSet>

org.eclipse.rdf4j.federated.evaluation.join.HashJoin

All Implemented Interfaces:

AutoCloseable, Runnable, Iterator<BindingSet>, CloseableIteration<BindingSet>, ParallelExecutor<BindingSet>

@Deprecated(forRemoval=true)
public class HashJoin
extends JoinExecutorBase<BindingSet>

Deprecated, for removal: This API element is subject to removal in a future version.

Operator for a hash join of tuple expressions.

Since:

6.0

Author:

Andreas Schwarte

Field Summary

Fields inherited from class JoinExecutorBase

bindings, joinVars, leftIter, rightArg

Modifier and Type	Field	Description
protected final BindingSet	bindings
protected Set<String>	joinVars
protected CloseableIteration<BindingSet>	leftIter
protected final TupleExpr	rightArg

Fields inherited from class ParallelExecutorBase

evaluationThread, executorId, finished, log, NEXT_EXECUTOR_ID, queryInfo, rightIter, rightQueue, strategy

Modifier and Type	Field	Description
protected Thread	evaluationThread
protected final long	executorId
protected boolean	finished
protected static final org.slf4j.Logger	log
protected static final AtomicLong	NEXT_EXECUTOR_ID
protected final QueryInfo	queryInfo
protected CloseableIteration<BindingSet>	rightIter
protected FedXQueueCursor<BindingSet>	rightQueue
protected final FederationEvalStrategy	strategy

Fields inherited from interface CloseableIteration

EMPTY_STATEMENT_ITERATION

Modifier and Type	Field	Description
static final EmptyIteration<Statement>	EMPTY_STATEMENT_ITERATION

Constructor Summary

Constructors

Constructor	Description
HashJoin(FederationEvalStrategy strategy, CloseableIteration<BindingSet> leftIter, TupleExpr rightArg, QueryEvaluationStep rightPrepared, Set<String> joinVars, BindingSet bindings, QueryInfo queryInfo)	Deprecated, for removal: This API element is subject to removal in a future version.

Method Summary

Modifier and Type	Method	Description
protected void	handleBindings()	Deprecated, for removal: This API element is subject to removal in a future version. Implementations must implement this method to handle bindings.
protected void	performJoin(Collection<BindingSet> leftBlock, Collection<BindingSet> rightBlock, Set<String> joinVariables, Collection<String> freeVariablesRight)	Deprecated, for removal: This API element is subject to removal in a future version. Perform the join and add the result to this cursor.

Methods inherited from class JoinExecutorBase

getExecutorType, getJoinVars, handleClose, performExecution, setJoinVars

Modifier and Type	Method	Description
protected String	getExecutorType()
Set<String>	getJoinVars()
void	handleClose()	Called by AbstractCloseableIteration.close() when it is called for the first time.
protected final void	performExecution()	Perform the parallel execution.
void	setJoinVars(Set<String> joinVars)	Set the join variables

Methods inherited from class ParallelExecutorBase

addResult, checkTimeout, done, getDisplayId, getId, getNextElement, getQueryInfo, isFinished, run, toss, toString

Modifier and Type	Method	Description
void	addResult(CloseableIteration<BindingSet> res)	Handle the result appropriately, e.g. add it to the result iteration.
protected void	checkTimeout()	Checks whether the query execution has run into a timeout.
void	done()	Inform the controlling instance that some job is done from a different thread.
String	getDisplayId()
protected String	getId()
BindingSet	getNextElement()	Gets the next element.
QueryInfo	getQueryInfo()	Return the query info of the associated query
boolean	isFinished()	Return true if this executor is finished or aborted
final void	run()
void	toss(Exception e)	Toss some exception to the controlling instance
String	toString()

Methods inherited from class LookAheadIteration

hasNext, next, remove

Modifier and Type	Method	Description
final boolean	hasNext()
final BindingSet	next()
void	remove()	Throws an UnsupportedOperationException.

Methods inherited from class AbstractCloseableIteration

close, isClosed

Modifier and Type	Method	Description
final void	close()	Calls AbstractCloseableIteration.handleClose() upon first call and makes sure the resource closures are only executed once.
final boolean	isClosed()	Checks whether this CloseableIteration has been closed.

Methods inherited from class Object

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

Methods inherited from interface CloseableIteration

stream

Modifier and Type	Method	Description
default Stream<BindingSet>	stream()	Convert the results to a Java 8 Stream.

Methods inherited from interface Iterator

forEachRemaining

Constructor Details

HashJoin

public HashJoin(FederationEvalStrategy strategy,
 CloseableIteration<BindingSet> leftIter,
 TupleExpr rightArg,
 QueryEvaluationStep rightPrepared,
 Set<String> joinVars,
 BindingSet bindings,
 QueryInfo queryInfo)
         throws QueryEvaluationException

Deprecated, for removal: This API element is subject to removal in a future version.

Throws:

QueryEvaluationException

Method Details

handleBindings

protected void handleBindings()
                       throws Exception

Deprecated, for removal: This API element is subject to removal in a future version.

Description copied from class: JoinExecutorBase

Implementations must implement this method to handle bindings. Use the following as a template while (!closed invalid input: '&'invalid input: '&' leftIter.hasNext()) { // your code } and add results to rightQueue. Note that addResult() is implemented synchronized and thus thread safe. In case you can guarantee sequential access, it is also possible to directly access rightQueue Note that the implementation must block until the entire join is executed.

Specified by:

handleBindings in class JoinExecutorBase<BindingSet>

Throws:

Exception

performJoin

protected void performJoin(Collection<BindingSet> leftBlock,
 Collection<BindingSet> rightBlock,
 Set<String> joinVariables,
 Collection<String> freeVariablesRight)

Deprecated, for removal: This API element is subject to removal in a future version.

Perform the join and add the result to this cursor.

See join(Collection, Collection, Set, Collection) and ParallelExecutorBase.addResult(CloseableIteration).

Parameters:

leftBlock -

rightBlock -

joinVariables -

freeVariablesRight -