com.bigdata.rdf.sail
Class FreeTextSearchExpander

java.lang.Object
  com.bigdata.rdf.sail.FreeTextSearchExpander

All Implemented Interfaces:

ISolutionExpander<ISPO>, Serializable

public class FreeTextSearchExpander
extends Object
implements ISolutionExpander<ISPO>

Class used to expand a StatementPattern involving a BNS.SEARCH magic predicate into the set of subjects having any of the tokens in the query.

Version:

$Id: FreeTextSearchExpander.java 2265 2009-10-26 12:51:06Z thompsonbry $

Author:

Bryan Thompson

See Also:

Serialized Form

Field Summary

protected static boolean	DEBUG
protected static boolean	INFO
protected static org.apache.log4j.Logger	log

Constructor Summary

FreeTextSearchExpander(AbstractTripleStore database, Literal query)

Method Summary

boolean	backchain() Add the backchainer on top of the expander.
IAccessPath<ISPO>	getAccessPath(IAccessPath<ISPO> accessPath) Return the IAccessPath that will be used to evaluate the IPredicate.
boolean	runFirst() If true, the predicate for this expander will be given priority in the join order.

Methods inherited from class java.lang.Object

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

Field Detail

log

protected static final org.apache.log4j.Logger log

INFO

protected static final boolean INFO

DEBUG

protected static final boolean DEBUG

Constructor Detail

FreeTextSearchExpander

public FreeTextSearchExpander(AbstractTripleStore database,
                              Literal query)

Method Detail

backchain

public boolean backchain()

Description copied from interface: ISolutionExpander

Add the backchainer on top of the expander.

Specified by:

backchain in interface ISolutionExpander<ISPO>

Returns:

true if the backchainer should run

runFirst

public boolean runFirst()

Description copied from interface: ISolutionExpander

If true, the predicate for this expander will be given priority in the join order.

Specified by:

runFirst in interface ISolutionExpander<ISPO>

Returns:

true if the predicate should be run first

getAccessPath

public IAccessPath<ISPO> getAccessPath(IAccessPath<ISPO> accessPath)

Description copied from interface: ISolutionExpander

Return the IAccessPath that will be used to evaluate the IPredicate.

Specified by:

getAccessPath in interface ISolutionExpander<ISPO>

Parameters:

accessPath - The IAccessPath that will be used by default.

Returns:

The IAccessPath that will be used. You can return the given accessPath or you can layer additional semantics onto or otherwise override the given IAccessPath.