Package org.eclipse.rdf4j.federated.optimizer

Class FilterOptimizer

java.lang.Object

org.eclipse.rdf4j.query.algebra.helpers.AbstractSimpleQueryModelVisitor<OptimizationException>

org.eclipse.rdf4j.federated.optimizer.FilterOptimizer

All Implemented Interfaces:

FedXOptimizer, QueryModelVisitor<OptimizationException>

public class FilterOptimizer
extends AbstractSimpleQueryModelVisitor<OptimizationException>
implements FedXOptimizer

Filter optimizer to push down FILTER expressions as far as possible.

Author:

Andreas Schwarte

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected static class	FilterOptimizer.FilterBindingFinder
protected static class	FilterOptimizer.FilterExprInsertVisitor
protected static class	FilterOptimizer.VarFinder

Constructor Summary

Constructors

Constructor	Description
FilterOptimizer()

Method Summary

Modifier and Type	Method	Description
protected void	getConjunctiveExpressions(ValueExpr expr, List<ValueExpr> conjExpr)	add the conjunctive expressions to specified list, has recursive step.
protected boolean	isCompatibleExpr(ValueExpr e)	returns true if this filter can be used for optimization.
void	meet(Filter filter)
void	meet(Service node)
void	optimize(TupleExpr tupleExpr)	Optimize the provided tuple expression

Methods inherited from class org.eclipse.rdf4j.query.algebra.helpers.AbstractSimpleQueryModelVisitor

meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meetBinaryTupleOperator, meetBinaryValueOperator, meetCompareSubQueryValueOperator, meetNAryValueOperator, meetOther, meetSubQueryValueOperator, meetUnaryTupleOperator, meetUnaryValueOperator, meetUnsupported, meetUpdateExpr

Methods inherited from class java.lang.Object

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

Constructor Details

FilterOptimizer

public FilterOptimizer()

Method Details

optimize

public void optimize(TupleExpr tupleExpr)

Description copied from interface: FedXOptimizer

Optimize the provided tuple expression

Specified by:

optimize in interface FedXOptimizer

Parameters:

tupleExpr -

meet

public void meet(Filter filter)

Specified by:

meet in interface QueryModelVisitor<OptimizationException>

Overrides:

meet in class AbstractSimpleQueryModelVisitor<OptimizationException>

meet

public void meet(Service node)
          throws OptimizationException

Specified by:

meet in interface QueryModelVisitor<OptimizationException>

Overrides:

meet in class AbstractSimpleQueryModelVisitor<OptimizationException>

Throws:

OptimizationException

getConjunctiveExpressions

protected void getConjunctiveExpressions(ValueExpr expr,
 List<ValueExpr> conjExpr)

add the conjunctive expressions to specified list, has recursive step.

Parameters:

expr - the expr, in the best case in CNF

conjExpr - the list to which expressions will be added

isCompatibleExpr

protected boolean isCompatibleExpr(ValueExpr e)

returns true if this filter can be used for optimization. Currently no conjunctive or disjunctive expressions are supported.

Parameters:

e -

Returns:

whether the expression is compatible