Package org.eclipse.rdf4j.sail.lucene

Class LuceneSailConnection

java.lang.Object

org.eclipse.rdf4j.sail.helpers.SailConnectionWrapper

org.eclipse.rdf4j.sail.helpers.NotifyingSailConnectionWrapper

org.eclipse.rdf4j.sail.lucene.LuceneSailConnection

All Implemented Interfaces:

AutoCloseable, FederatedServiceResolverClient, org.eclipse.rdf4j.sail.features.ThreadSafetyAware, NotifyingSailConnection, SailConnection

public class LuceneSailConnection
extends org.eclipse.rdf4j.sail.helpers.NotifyingSailConnectionWrapper

Sail Connection Listener instead of implementing add/remove

Using SailConnectionListener, see above The LuceneIndex is adapted based on events coming from the wrapped Sail, rather than by overriding the addStatement and removeStatements methods. This approach has two benefits: (1) when the wrapped Sail only reports statements that were not stored before, the LuceneIndex does not have to do the check on the skipped statemements and (2) the method for removing Statements from the Lucene index does not have to take wildcards into account, making its implementation simpler.

Synchronized Methods

LuceneSailConnection uses a listener to collect removed statements. The listener should not be active during the removal of contexts, as this is not needed (context removal is implemented differently). To realize this, all methods that can do changes are synchronized and during context removal, the listener is disabled. Thus, all methods of this connection that can change data are synchronized.

Evaluating Queries - possible optimizations

Arjohn has answered this question in the sesame-dev mailinglist on 13.8.2007: Is there a QueryModelNode that can contain a fixed (perhaps very long) list of Query result bindings? There is currently no such node, but there are two options to get similar behaviour: 1) Include the result bindings as OR-ed constraints in the query model. E.g. if you have a result binding like {{x=1,y=1},{x=2,y=2}}, this translates to the constraints (x=1 and y=1) or (x=2 and y=2). 2) The LuceneSail could iterate over the LuceneQueryResult and supply the various results as query input parameters to the underlying Sail. This is similar to using PreparedStatement's in JDBC.

Author:

sauermann, christian.huetter

Field Summary

Fields

Modifier and Type	Field	Description
protected SailConnectionListener	connectionListener	The listener that listens to the underlying connection.

Constructor Summary

Constructors

Constructor	Description
LuceneSailConnection(NotifyingSailConnection wrappedConnection, SearchIndex luceneIndex, LuceneSail sail)

Method Summary

Modifier and Type	Method	Description
void	addStatement(org.eclipse.rdf4j.model.Resource subj, org.eclipse.rdf4j.model.IRI pred, org.eclipse.rdf4j.model.Value obj, org.eclipse.rdf4j.model.Resource... contexts)
void	begin()
void	clear(org.eclipse.rdf4j.model.Resource... contexts)
void	close()
void	commit()
org.eclipse.rdf4j.common.iteration.CloseableIteration<? extends org.eclipse.rdf4j.query.BindingSet,org.eclipse.rdf4j.query.QueryEvaluationException>	evaluate(org.eclipse.rdf4j.query.algebra.TupleExpr tupleExpr, org.eclipse.rdf4j.query.Dataset dataset, org.eclipse.rdf4j.query.BindingSet bindings, boolean includeInferred)
void	removeStatements(org.eclipse.rdf4j.model.Resource subj, org.eclipse.rdf4j.model.IRI pred, org.eclipse.rdf4j.model.Value obj, org.eclipse.rdf4j.model.Resource... contexts)
void	rollback()

Methods inherited from class org.eclipse.rdf4j.sail.helpers.NotifyingSailConnectionWrapper

addConnectionListener, getWrappedConnection, removeConnectionListener

Methods inherited from class org.eclipse.rdf4j.sail.helpers.SailConnectionWrapper

addStatement, begin, clearNamespaces, endUpdate, explain, flush, getContextIDs, getFederatedServiceResolver, getNamespace, getNamespaces, getStatements, hasStatement, isActive, isOpen, pendingRemovals, prepare, prepareQuery, removeNamespace, removeStatement, setFederatedServiceResolver, setNamespace, setTransactionSettings, size, size, startUpdate, supportsConcurrentReads

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.eclipse.rdf4j.sail.SailConnection

addStatement, begin, clearNamespaces, endUpdate, explain, flush, getContextIDs, getNamespace, getNamespaces, getStatements, hasStatement, isActive, isOpen, pendingRemovals, prepare, prepareQuery, removeNamespace, removeStatement, setNamespace, setTransactionSettings, size, startUpdate

Field Detail

connectionListener

protected final SailConnectionListener connectionListener

The listener that listens to the underlying connection. It is disabled during clearContext operations.

Constructor Detail

LuceneSailConnection

public LuceneSailConnection(NotifyingSailConnection wrappedConnection,
                            SearchIndex luceneIndex,
                            LuceneSail sail)

Method Detail

addStatement

public void addStatement(org.eclipse.rdf4j.model.Resource subj,
                         org.eclipse.rdf4j.model.IRI pred,
                         org.eclipse.rdf4j.model.Value obj,
                         org.eclipse.rdf4j.model.Resource... contexts)
                  throws SailException

Specified by:

addStatement in interface SailConnection

Overrides:

addStatement in class org.eclipse.rdf4j.sail.helpers.SailConnectionWrapper

Throws:

SailException

close

public void close()
           throws SailException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface SailConnection

Overrides:

close in class org.eclipse.rdf4j.sail.helpers.SailConnectionWrapper

Throws:

SailException

clear

public void clear(org.eclipse.rdf4j.model.Resource... contexts)
           throws SailException

Specified by:

clear in interface SailConnection

Overrides:

clear in class org.eclipse.rdf4j.sail.helpers.SailConnectionWrapper

Throws:

SailException

begin

public void begin()
           throws SailException

Specified by:

begin in interface SailConnection

Overrides:

begin in class org.eclipse.rdf4j.sail.helpers.SailConnectionWrapper

Throws:

SailException

commit

public void commit()
            throws SailException

Specified by:

commit in interface SailConnection

Overrides:

commit in class org.eclipse.rdf4j.sail.helpers.SailConnectionWrapper

Throws:

SailException

evaluate

public org.eclipse.rdf4j.common.iteration.CloseableIteration<? extends org.eclipse.rdf4j.query.BindingSet,org.eclipse.rdf4j.query.QueryEvaluationException> evaluate(org.eclipse.rdf4j.query.algebra.TupleExpr tupleExpr,
                                                                                                                                                                           org.eclipse.rdf4j.query.Dataset dataset,
                                                                                                                                                                           org.eclipse.rdf4j.query.BindingSet bindings,
                                                                                                                                                                           boolean includeInferred)
                                                                                                                                                                    throws SailException

Specified by:

evaluate in interface SailConnection

Overrides:

evaluate in class org.eclipse.rdf4j.sail.helpers.SailConnectionWrapper

Throws:

SailException

removeStatements

public void removeStatements(org.eclipse.rdf4j.model.Resource subj,
                             org.eclipse.rdf4j.model.IRI pred,
                             org.eclipse.rdf4j.model.Value obj,
                             org.eclipse.rdf4j.model.Resource... contexts)
                      throws SailException

Specified by:

removeStatements in interface SailConnection

Overrides:

removeStatements in class org.eclipse.rdf4j.sail.helpers.SailConnectionWrapper

Throws:

SailException

rollback

public void rollback()
              throws SailException

Specified by:

rollback in interface SailConnection

Overrides:

rollback in class org.eclipse.rdf4j.sail.helpers.SailConnectionWrapper

Throws:

SailException