Class ExecOpBindJoinBRTPF

java.lang.Object

se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.BaseForExecOps

se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.UnaryExecutableOpBase

se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.UnaryExecutableOpBaseWithBatching

se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.BaseForExecOpBindJoinWithRequestOps<TriplePattern,BRTPFServer>

se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.ExecOpBindJoinBRTPF

All Implemented Interfaces:

StatsProvider, ExecutableOperator, UnaryExecutableOp

public class ExecOpBindJoinBRTPF
extends BaseForExecOpBindJoinWithRequestOps<TriplePattern,BRTPFServer>

Implementation of (a batching version of) the bind join algorithm for cases in which the federation member accessed by the algorithm supports the brTPF interface. For every batch of solution mappings from the input, the algorithm of this operator sends a brTPF request to the federation member; this request consists of the given triple pattern and the solutions of the current input batch (in fact, the algorithm may also decide to split the input batch into smaller batches for multiple requests). The response to such a request are all triples that i) match the triple pattern and ii) are compatible with at least one of the solutions that were attached to the request. After receiving such a response, the algorithm creates solution mappings from the received triples, joins these solution mappings locally with the solutions in the batch used for making the request, and then outputs the resulting joined solutions (if any). Thereafter, the algorithm moves on to the next batch of solutions from the input.

Nested Class Summary

Nested classes/interfaces inherited from class se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.BaseForExecOpBindJoinWithRequestOps

BaseForExecOpBindJoinWithRequestOps.MyIntermediateResultElementSink, BaseForExecOpBindJoinWithRequestOps.MyIntermediateResultElementSinkOuterJoin

Field Summary

Fields

Modifier and Type	Field	Description
static final int	DEFAULT_BATCH_SIZE

Fields inherited from class se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.BaseForExecOpBindJoinWithRequestOps

fm, minimumRequestBlockSize, numberOfRequestOpsUsed, query, requestBlockSize, requestBlockSizeWasReduced, statsOfFirstReqOp, statsOfLastReqOp, useOuterJoinSemantics, varsInPatternForFM

Fields inherited from class se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.UnaryExecutableOpBaseWithBatching

batchSize, collectedInputSolMaps

Fields inherited from class se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.BaseForExecOps

collectExceptions

Constructor Summary

Constructors

Constructor	Description
ExecOpBindJoinBRTPF(TriplePattern tp, BRTPFServer fm, boolean useOuterJoinSemantics, boolean collectExceptions)
ExecOpBindJoinBRTPF(TriplePattern tp, BRTPFServer fm, boolean useOuterJoinSemantics, int batchSize, boolean collectExceptions)

Method Summary

Modifier and Type	Method	Description
protected NullaryExecutableOp	createExecutableReqOp(Iterable<SolutionMapping> inputSolMaps)	Implementations of this function should create an executable operator that can perform a bind join request in which the query of this bind join operator is combined with the given solution mappings.
static Set<SolutionMapping>	restrictSolMaps(Iterable<SolutionMapping> inputSolMaps, Set<org.apache.jena.sparql.core.Var> joinVars)	Returns null if at least one of the solution mappings that would otherwise be added to the returned set of solution mappings is the empty solution mapping (in which case this operator better uses a TPF request rather than a brTPF request).

Methods inherited from class se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.BaseForExecOpBindJoinWithRequestOps

_concludeExecution, _processBatch, _processJoinableInput, _processWithoutSplittingInputFirst, createStats, extractUnjoinableInputSMs, reduceRequestBlockSize, resetStats

Methods inherited from class se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.UnaryExecutableOpBaseWithBatching

_concludeExecution, _process

Methods inherited from class se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.UnaryExecutableOpBase

_process, concludeExecution, getStats, process, process

Methods inherited from class se.liu.ida.hefquin.engine.queryplan.executable.impl.ops.BaseForExecOps

getExceptionsCaughtDuringExecution, recordExceptionCaughtDuringExecution

Methods inherited from class java.lang.Object

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

Methods inherited from interface se.liu.ida.hefquin.engine.queryplan.executable.ExecutableOperator

getExceptionsCaughtDuringExecution

Field Details

DEFAULT_BATCH_SIZE

public static final int DEFAULT_BATCH_SIZE

See Also:

• Constant Field Values

Constructor Details

ExecOpBindJoinBRTPF

public ExecOpBindJoinBRTPF(TriplePattern tp,
 BRTPFServer fm,
 boolean useOuterJoinSemantics,
 int batchSize,
 boolean collectExceptions)

ExecOpBindJoinBRTPF

public ExecOpBindJoinBRTPF(TriplePattern tp,
 BRTPFServer fm,
 boolean useOuterJoinSemantics,
 boolean collectExceptions)

Method Details

createExecutableReqOp

protected NullaryExecutableOp createExecutableReqOp(Iterable<SolutionMapping> inputSolMaps)

Description copied from class: BaseForExecOpBindJoinWithRequestOps

Implementations of this function should create an executable operator that can perform a bind join request in which the query of this bind join operator is combined with the given solution mappings. The operator created by this function should throws exceptions instead of collecting them.

Specified by:

createExecutableReqOp in class BaseForExecOpBindJoinWithRequestOps<TriplePattern,BRTPFServer>

restrictSolMaps

public static Set<SolutionMapping> restrictSolMaps(Iterable<SolutionMapping> inputSolMaps,
 Set<org.apache.jena.sparql.core.Var> joinVars)

Returns null if at least one of the solution mappings that would otherwise be added to the returned set of solution mappings is the empty solution mapping (in which case this operator better uses a TPF request rather than a brTPF request).