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

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.BaseForExecOpBindJoin<QueryType,MemberType>

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

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

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

defaultPreferredInputBlockSize, fm, query

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

timeAtCurrentProcStart

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)

Method Summary

Modifier and Type	Method	Description
protected NullaryExecutableOp	createExecutableRequestOperator(Iterable<SolutionMapping> inputSolMaps)	The returned operator should be created such that it throws exceptions instead of collecting them.
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

_process, _process, _processWithoutSplittingInputFirst, createStats, extractUnjoinableInputSMs, reduceRequestBlockSize, resetStats

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

_concludeExecution, preferredInputBlockSize

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

concludeExecution, getStats, 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

Constructor Details

ExecOpBindJoinBRTPF

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

Method Details

createExecutableRequestOperator

protected NullaryExecutableOp createExecutableRequestOperator(Iterable<SolutionMapping> inputSolMaps)

Description copied from class: BaseForExecOpBindJoinWithRequestOps

The returned operator should be created such that it throws exceptions instead of collecting them.

Specified by:

createExecutableRequestOperator 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).