org.openrdf.sesame.query.rql.model
Class UnknownSelector

java.lang.Object
  org.openrdf.sesame.query.rql.model.UnknownSelector

All Implemented Interfaces:

Selector

public class UnknownSelector

extends Object

implements Selector

UnknownSelector is a preprocessing object which is necessary because it is not always possible at parsing time to decide whether a path expresion is a InstanceSelector or a DataPathSelector. This happens when a path expression of the form "url{VAR}" is encountered.

Constructor Summary

UnknownSelector(URI uri, DataVar var)

Method Summary

void	clear() Clears the Selector.
void	initialize(RdfSchemaSource rss) Gives the Selector the opportunity to initialize itself.
boolean	isInstanceSelector(RdfSchemaSource rss) Determines whether the selector is a ResourceSelector by checking whether the URI is a known Class.
boolean	selectNext(RdfSchemaSource rss) Selects the next values.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

UnknownSelector

public UnknownSelector(URI uri,
                       DataVar var)

Method Detail

isInstanceSelector

public boolean isInstanceSelector(RdfSchemaSource rss)

Determines whether the selector is a ResourceSelector by checking whether the URI is a known Class.

initialize

public void initialize(RdfSchemaSource rss)
                throws QueryEvaluationException

Description copied from interface: Selector

Gives the Selector the opportunity to initialize itself.

Specified by:

initialize in interface Selector

Throws:

QueryEvaluationException

selectNext

public boolean selectNext(RdfSchemaSource rss)
                   throws QueryEvaluationException

Description copied from interface: Selector

Selects the next values. Returns true if the selection was successful, false otherwise.

Specified by:

selectNext in interface Selector

Throws:

QueryEvaluationException

clear

public void clear()

Description copied from interface: Selector

Clears the Selector. The Selector will release all resources it is currently using. After the Selector has been cleared it should be reusable by re-initializing it.

Specified by:

clear in interface Selector

toString

public String toString()