org.openanzo.server.repository.query.predicates
Class TextLikePredicate

java.lang.Object
  org.openanzo.server.repository.query.predicates.TextLikePredicate

All Implemented Interfaces:

FunctionalPredicate

public class TextLikePredicate
extends java.lang.Object
implements FunctionalPredicate

Special predicate that allows one to use a SQL like query to match literal values.

Example: SELECT ?S WHERE {?s 'test%'}

Author:

Matthew Roy ( mroy@cambridgesemantics.com )

Constructor Summary

TextLikePredicate()

Method Summary

boolean	canBindGraphVariables()
SolutionSet	generateSolutions(IRIReference namedGraph, Variable namedGraphVariable, SolutionSet bindingConstraints) Requests that solutions be generated against the default graph, a particular named graph, or spanning the named graphs (with a named graph variable).
double	getCost(NodeCostModel costModel)
TriplePattern	getFunctionalTriplePattern() Accessor for the triple pattern set with FunctionalPredicate.setFunctionalTriplePattern(TriplePattern).
java.lang.String	getTextQuery() Get the query text
Variable	getVariable() Get the variable
boolean	handlesTriplePattern(TriplePattern pattern) After setFunctionalTriplePattern has been called, this method is called once for every triple pattern in the functional triple pattern's basic graph pattern (BGP).
void	initialize(QueryInformation qi)
void	setFunctionalTriplePattern(TriplePattern pattern) This is the first method invoked on a FunctionalPredicate.
boolean	usesDataFromGraphs()

Methods inherited from class java.lang.Object

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

Constructor Detail

TextLikePredicate

public TextLikePredicate()

Method Detail

initialize

public void initialize(QueryInformation qi)

Specified by:

initialize in interface FunctionalPredicate

Parameters:

qi - Information on the current query executing

canBindGraphVariables

public boolean canBindGraphVariables()

Specified by:

canBindGraphVariables in interface FunctionalPredicate

Returns:

true if this FP will handle binding graph variables.

getVariable

public Variable getVariable()

Get the variable

Returns:

the variable

getTextQuery

public java.lang.String getTextQuery()

Get the query text

Returns:

the textMatch

generateSolutions

public SolutionSet generateSolutions(IRIReference namedGraph,
                                     Variable namedGraphVariable,
                                     SolutionSet bindingConstraints)
                              throws GlitterException

Description copied from interface: FunctionalPredicate

Requests that solutions be generated against the default graph, a particular named graph, or spanning the named graphs (with a named graph variable).

Specified by:

generateSolutions in interface FunctionalPredicate

Parameters:

namedGraph - If not null, the named graph to use for generating bindings

namedGraphVariable - If not null, the functional predicate should generate solutions that bind this variable to the appropriate graph IRI for each solution generated.

bindingConstraints - Existing constraints on variables. This FunctionalPredicate can assume that the engine will conjoin the solutions it returns with these constraints. (And so can eliminate any solutions that would not add to a result set, if it wishes.)

Returns:

A SolutionSet from generating bindings using the logic of this functional predicate.

Throws:

GlitterException

handlesTriplePattern

public boolean handlesTriplePattern(TriplePattern pattern)
                             throws FunctionalPredicateInvocationException

Description copied from interface: FunctionalPredicate

After setFunctionalTriplePattern has been called, this method is called once for every triple pattern in the functional triple pattern's basic graph pattern (BGP).

Specified by:

handlesTriplePattern in interface FunctionalPredicate

Parameters:

pattern - A triple pattern from the same BGP that the functional triple pattern came from.

Returns:

true if this FunctionalPredicate will handle (and generate bindings for) this triple pattern; false otherwise.

Throws:

FunctionalPredicateInvocationException

setFunctionalTriplePattern

public void setFunctionalTriplePattern(TriplePattern pattern)
                                throws FunctionalPredicateInvocationException

Description copied from interface: FunctionalPredicate

This is the first method invoked on a FunctionalPredicate. It sets the triple pattern which contains the functional predicate. The FunctionalPredicate implementation should save this information; it can also throw a FunctionalPredicateInvocationException if it does not wish to handle this triple pattern (for example, if it can not handle subject variables and this is a ?s ex:pred ?o triple pattern.

Specified by:

setFunctionalTriplePattern in interface FunctionalPredicate

Parameters:

pattern - the triple pattern which contains the functional predicate

Throws:

FunctionalPredicateInvocationException

usesDataFromGraphs

public boolean usesDataFromGraphs()

Specified by:

usesDataFromGraphs in interface FunctionalPredicate

Returns:

true if this FP needs to examine graphs to get at data

getCost

public double getCost(NodeCostModel costModel)

Specified by:

getCost in interface FunctionalPredicate

Parameters:

costModel - The cost model being used to generate an execution plan. This functional predicate can investigate the cost of various other types of nodes using this supplied cost model in order to generate its own estimate.

Returns:

An estimated cost of evaluating this functional-predicate node.

getFunctionalTriplePattern

public TriplePattern getFunctionalTriplePattern()

Description copied from interface: FunctionalPredicate

Accessor for the triple pattern set with FunctionalPredicate.setFunctionalTriplePattern(TriplePattern).

Specified by:

getFunctionalTriplePattern in interface FunctionalPredicate

Returns:

The TriplePattern that contains this functional predicate.