org.openrdf.repository.RepositoryConnection Java Examples

/**
 * Issue the query.
 * 
 * @throws Exception
 */
private void doQuery() throws Exception {
   
    RepositoryConnection cxn = repo.getReadOnlyConnection();
    try {

        final TupleQuery tupleQuery = 
            cxn.prepareTupleQuery(QueryLanguage.SPARQL, query);
        tupleQuery.setIncludeInferred(true /* includeInferred */);
        TupleQueryResult result = tupleQuery.evaluate();
        // do something with the results
        int resultCount = 0;
        while (result.hasNext()) {
            BindingSet bindingSet = result.next();
            // log.info(bindingSet);
            resultCount++;
        }
        log.info(resultCount + " results");
        
    } finally {
        // close the repository connection
        cxn.close();
    }
        
}
 

private void addDuringQueryExec(final RepositoryConnection conn,
	final Resource subj, final URI pred, final Value obj,
	final Resource... ctx) throws RepositoryException,
	MalformedQueryException, QueryEvaluationException {
final TupleQuery tq = conn.prepareTupleQuery(QueryLanguage.SPARQL,
      		"select distinct ?s ?p ?o where{?s ?p ?t . ?t <http://www.w3.org/2000/01/rdf-schema#subClassOf> ?o }"
      		);
      tq.setBinding("s", subj);
      tq.setBinding("p", pred);
      tq.setBinding("o", obj);
      final TupleQueryResult tqr = tq.evaluate();
      try {
          if (!tqr.hasNext()) {
              conn.add(subj, pred, obj, ctx);
          }
      } finally {
          tqr.close();
      }
  }
 

private int getSize(Repository repository) throws RepositoryException {
	int size = 0;
	RepositoryConnection connection = null;
	RepositoryResult<Statement> iter = null;
	try {
		connection = repository.getConnection();
		iter = connection.getStatements(null, null, null, false);
		while (iter.hasNext()) {
			iter.next();
			++size;
		}
	} finally {
		if (iter != null)
			iter.close();
		if (connection != null)
			connection.close();
	}
	return size;
}
 

private void addData(final RepositoryConnection conn) throws IOException,
		RDFParseException, RepositoryException, RDFHandlerException {

    final RDFParser rdfParser = Rio.createParser(RDFFormat.NTRIPLES,
			conn.getValueFactory());
	rdfParser.setVerifyData(true);
	rdfParser.setStopAtFirstError(true);
	rdfParser.setDatatypeHandling(RDFParser.DatatypeHandling.IGNORE);
	rdfParser.setRDFHandler(new RDFHandlerBase() {
		@Override
		public void handleStatement(Statement st)
				throws RDFHandlerException {
			try {
				conn.add(st);
			} catch (OpenRDFException e) {
				throw new RDFHandlerException(e);
			}
		}
	});
	rdfParser.parse(getClass().getResourceAsStream("TestTicket276.n3"), "");
}
 

private void executeQuery(final RepositoryConnection conn, final String string, final double start, final double length, final String expected)
		throws RepositoryException, MalformedQueryException,
		QueryEvaluationException, RDFParseException, IOException, VisitorException {

	final ValueFactory vf = conn.getValueFactory();
	final String query = "select ?substring WHERE { BIND ( SUBSTR(?string, ?start, ?length) as ?substring ) . }";
	final TupleQuery q = conn.prepareTupleQuery(QueryLanguage.SPARQL, query);
	q.setBinding("string", vf.createLiteral(string));
	q.setBinding("start", vf.createLiteral(start));
	q.setBinding("length", vf.createLiteral(length));
	final TupleQueryResult tqr = q.evaluate();
	try {
		while (tqr.hasNext()) {
			final BindingSet bindings = tqr.next();
			// assert expected value
			assertEquals(expected, bindings.getBinding("substring").getValue().stringValue());
		}
	} finally {
		tqr.close();
	}
}
 

/**
 * Tuple pattern query - find all statements with the pattern, where null is
 * a wildcard
 * 
 * @param s
 *            subject (null for wildcard)
 * @param p
 *            predicate (null for wildcard)
 * @param o
 *            object (null for wildcard)
 * @param contexts
 *            varArgs contexts (use default graph if null)
 * @return serialized graph of results
 */
public List<Statement> tuplePattern(Resource s, URI p, Value o,
		Resource... contexts) {
	try {
		RepositoryConnection con = currentRepository.getConnection();
		try {
			RepositoryResult<Statement> repres = con.getStatements(s, p, o,
					true, contexts);
			ArrayList<Statement> reslist = new ArrayList<Statement>();
			while (repres.hasNext()) {
				reslist.add(repres.next());
			}
			return reslist;
		} finally {
			con.close();
		}
	} catch (Exception e) {
		e.printStackTrace();
	}
	return null;
}
 

private void executeQuery(final RepositoryConnection conn, final Literal string, final int start, final Literal expected)
		throws RepositoryException, MalformedQueryException, QueryEvaluationException {
	final ValueFactory vf = conn.getValueFactory();
	final String query = "select ?substring WHERE { BIND ( SUBSTR(?string, ?start) as ?substring ) . }";
	final TupleQuery q = conn.prepareTupleQuery(QueryLanguage.SPARQL, query);
	q.setBinding("string", string);
	q.setBinding("start", vf.createLiteral(start));
	final TupleQueryResult tqr = q.evaluate();
	try {
		while (tqr.hasNext()) {
			final BindingSet bindings = tqr.next();
			// assert expected value
			assertEquals(expected, bindings.getBinding("substring").getValue());
		}
	} finally {
		tqr.close();
	}
}
 

@Override
public Set<String> contextNames() {
    HashSet<String> names = new HashSet<>();
    RepositoryConnection conn = null;
    try {
        conn = repo.getConnection();
        RepositoryResult<Resource> rs = conn.getContextIDs();
        while (rs.hasNext()) {
            names.add(rs.next().stringValue());
        }
        return names;
    } catch (RepositoryException x) {
        LOG.error("getting context names : {}", x.getMessage());
    } finally {
        closeConnection(conn, "Getting context names");
    }
    return names;
}
 

@Override
public void write(DataSource ds, String contextName) {
    RepositoryConnection conn = null;
    try {
        conn = repo.getConnection();
        RepositoryResult<Resource> contexts = conn.getContextIDs();
        while (contexts.hasNext()) {
            Resource context = contexts.next();
            if (context.stringValue().equals(contextName)) {
                write(ds, conn, context);
            }
        }
    } catch (RepositoryException x) {
        throw new TripleStoreException(String.format("Writing on %s", ds), x);
    } finally {
        closeConnection(conn, "Writing on " + ds);
    }
}
 

@Override
public void write(DataSource ds) {
    RepositoryConnection conn = null;
    try {
        conn = repo.getConnection();
        RepositoryResult<Resource> contexts = conn.getContextIDs();
        while (contexts.hasNext()) {
            Resource context = contexts.next();
            write(ds, conn, context);
        }
    } catch (RepositoryException x) {
        throw new TripleStoreException(String.format("Writing on %s", ds), x);
    } finally {
        closeConnection(conn, "Writing on " + ds);
    }
}
 

/**
 * Literal factory
 * 
 * @param s
 *            the literal value
 * @param typeuri
 *            uri representing the type (generally xsd)
 * @return
 */
public org.openrdf.model.Literal Literal(String s, URI typeuri) {
	try {
		RepositoryConnection con = currentRepository.getConnection();
		try {
			ValueFactory vf = con.getValueFactory();
			if (typeuri == null) {
				return vf.createLiteral(s);
			} else {
				return vf.createLiteral(s, typeuri);
			}
		} finally {
			con.close();
		}
	} catch (Exception e) {
		e.printStackTrace();
		return null;
	}
}
 

@Override
public void read(InputStream is, String base, String name) {
    RepositoryConnection cnx = null;
    try {
        cnx = repo.getConnection();
        cnx.begin();
        Resource context = context(cnx, name);
        read(is, base, name, cnx, context);
        cnx.commit();
        addNamespaceForBase(cnx, base);
    } catch (RepositoryException x) {
        throw new TripleStoreException(String.format("Reading. Repo problem %s %s", name, base), x);
    } finally {
        closeConnection(cnx, "Reading");
    }
}
 

/**
 * Creates a new ObjectConnection that will need to be closed by the caller.
 */
@Override
public ObjectConnection getConnection() throws RepositoryException {
	BlobStore blobs;
	try {
		blobs = getBlobStore();
	} catch (ObjectStoreConfigException e) {
		throw new RepositoryException(e);
	}
	ObjectFactory factory = service.createObjectFactory();
	RepositoryConnection conn = getDelegate().getConnection();
	ObjectConnection con = new ObjectConnection(this, conn, factory,
			createTypeManager(), blobs, idGenerator);
	con.setIncludeInferred(isIncludeInferred());
	con.setMaxQueryTime(getMaxQueryTime());
	// con.setQueryResultLimit(getQueryResultLimit());
	con.setQueryLanguage(getQueryLanguage());
	con.setReadContexts(getReadContexts());
	con.setAddContexts(getAddContexts());
	con.setRemoveContexts(getRemoveContexts());
	con.setArchiveContexts(getArchiveContexts());
	return con;
}
 

/**
 * update the namespace.
 * 
 * @param repository the Repository object
 * @param request the HttpServletRequest object
 * @param prefix the prefix
 * @return EmptySuccessView object if success
 * @throws IOException throws if there is error reading the namespace from the HttpServletRequest
 * @throws ClientHTTPException throws if No namespace name found in request body
 * @throws ServerHTTPException throws when there is error about the repository
 */
private ModelAndView getUpdateNamespaceResult(final Repository repository, final HttpServletRequest request, final String prefix)
		throws IOException, ClientHTTPException, ServerHTTPException {
	String namespace = IOUtil.readString(request.getReader());
	namespace = namespace.trim();

	if (namespace.length() == 0) {
		throw new ClientHTTPException(SC_BAD_REQUEST, "No namespace name found in request body");
	}

	try {
		RepositoryConnection repositoryCon = repository.getConnection();
		synchronized (repositoryCon) {
			repositoryCon.setNamespace(prefix, namespace);
		}
		repositoryCon.close();
	} catch (RepositoryException e) {
		throw new ServerHTTPException("Repository error: " + e.getMessage(), e);
	}

	return new ModelAndView(EmptySuccessView.getInstance());
}
 

private void executeQuery(final RepositoryConnection conn, final Literal string, final int start, final int length, final Literal expected)
		throws RepositoryException, MalformedQueryException, QueryEvaluationException {
	final ValueFactory vf = conn.getValueFactory();
	final String query = "select ?substring WHERE { BIND ( SUBSTR(?string, ?start, ?length) as ?substring ) . }";
	final TupleQuery q = conn.prepareTupleQuery(QueryLanguage.SPARQL, query);
	q.setBinding("string", string);
	q.setBinding("start", vf.createLiteral(start));
	q.setBinding("length", vf.createLiteral(length));
	final TupleQueryResult tqr = q.evaluate();
	try {
		while (tqr.hasNext()) {
			final BindingSet bindings = tqr.next();
			// assert expected value
			assertEquals(expected, bindings.getBinding("substring").getValue());
		}
	} finally {
		tqr.close();
	}
}
 

/**
 * Get total number of distinct subjects of a dataset
 * @return count 
 */
public static long getSubjectCount(String endpoint) throws Exception {
	String strQuery = "SELECT  (COUNT(DISTINCT ?s) AS ?sbjts) " + // 
			"WHERE " +
			"{" +
       		"?s ?p ?o " +
       		"} " ;
	SPARQLRepository repo = new SPARQLRepository(endpoint);
	repo.initialize();
	RepositoryConnection conn = repo.getConnection();
	try {
		TupleQuery query = conn.prepareTupleQuery(QueryLanguage.SPARQL, strQuery); 
		TupleQueryResult rs = query.evaluate();
		return Long.parseLong(rs.next().getValue("sbjts").stringValue());
	} finally {
		conn.close();
		repo.shutDown();
	}
}
 

/**
 * Tests basic object creation and persistence of triples.
 */
@Test
public void testCreate() throws Exception {
    // Create an Anno4j instance and get its repository connection for direct triple access:
    Anno4j anno4j = new Anno4j(new SailRepository(new MemoryStore()), null, false);
    RepositoryConnection repoConnection = anno4j.getRepository().getConnection();

    // Test simple object creation:
    Person p = anno4j.createObject(Person.class, (Resource) new URIImpl("urn:anno4j_test:p1"));
    p.setMbox("[email protected]");

    // Two statments (rdf:type, foaf:mbox) should be created:
    Collection<Statement> statements = getStatements(repoConnection);
    assertEquals(2, statements.size());
    assertTrue(statements.contains(new StatementImpl(new URIImpl("urn:anno4j_test:p1"),
                                                     new URIImpl(RDF.TYPE),
                                                     new URIImpl(FOAF.PERSON))));
    assertTrue(statements.contains(new StatementImpl(new URIImpl("urn:anno4j_test:p1"),
            new URIImpl(FOAF.MBOX),
            new LiteralImpl("[email protected]"))));
}
 

protected void uploadDataset(Dataset dataset)
	throws Exception
{
	RepositoryConnection con = dataRep.getConnection();
	try {
		// Merge default and named graphs to filter duplicates
		Set<URI> graphURIs = new HashSet<URI>();
		graphURIs.addAll(dataset.getDefaultGraphs());
		graphURIs.addAll(dataset.getNamedGraphs());

		for (Resource graphURI : graphURIs) {
			upload(((URI)graphURI), graphURI);
		}
	}
	finally {
		con.close();
	}
}
 

/**
 * Get Predicate List
 * @param endPointUrl SPARQL endPoint Url
 * @param graph Named graph
 * @return  predLst Predicates List
 */
private static List<String> getPredicates(String endPointUrl, String graph) throws Exception
{
	List<String>  predLst = new ArrayList<String>();
	String strQuery = getPredQuery(graph);
	SPARQLRepository repo = new SPARQLRepository(endPointUrl);
	repo.initialize();
	RepositoryConnection conn = repo.getConnection();
	try {
		TupleQuery query = conn.prepareTupleQuery(QueryLanguage.SPARQL, strQuery); 
		TupleQueryResult res = query.evaluate();
		while (res.hasNext()) 
		{
			String pred = res.next().getValue("p").toString();
			predLst.add(pred);	  		
		}
	} finally {
		conn.close();
		repo.shutDown();
	}
	return predLst;
}
 

public String printRDF(RDFFormat outform) {
	try {
		RepositoryConnection con = currentRepository.getConnection();
		try {
			ByteArrayOutputStream out = new ByteArrayOutputStream();
			RDFWriter w = Rio.createWriter(outform, out);

			con.export(w);
			String result = new String(out.toByteArray(), "UTF-8");
			return result;
		} finally {
			con.close();
		}
	} catch (Exception e) {
		e.printStackTrace();
	}
	return null;
}
 

/**
 * Execute a CONSTRUCT/DESCRIBE SPARQL query against the graphs
 * 
 * @param qs
 *            CONSTRUCT or DESCRIBE SPARQL query
 * @param format
 *            the serialization format for the returned graph
 * @return serialized graph of results
 */
public String runSPARQL(String qs, RDFFormat format) {
	try {
		RepositoryConnection con = currentRepository.getConnection();
		try {
			GraphQuery query = con.prepareGraphQuery(
					org.openrdf.query.QueryLanguage.SPARQL, qs);
			StringWriter stringout = new StringWriter();
			RDFWriter w = Rio.createWriter(format, stringout);
			query.evaluate(w);
			return stringout.toString();
		} finally {
			con.close();
		}
	} catch (Exception e) {
		e.printStackTrace();
	}
	return null;
}
 

protected static String getManifestName(Repository manifestRep, RepositoryConnection con,
		String manifestFileURL)
	throws QueryEvaluationException, RepositoryException, MalformedQueryException
{
	// Try to extract suite name from manifest file
	TupleQuery manifestNameQuery = con.prepareTupleQuery(QueryLanguage.SERQL,
			"SELECT ManifestName FROM {ManifestURL} rdfs:label {ManifestName}");
	manifestNameQuery.setBinding("ManifestURL", manifestRep.getValueFactory().createURI(manifestFileURL));
	TupleQueryResult manifestNames = manifestNameQuery.evaluate();
	try {
		if (manifestNames.hasNext()) {
			return manifestNames.next().getValue("ManifestName").stringValue();
		}
	}
	finally {
		manifestNames.close();
	}

	// Derive name from manifest URL
	int lastSlashIdx = manifestFileURL.lastIndexOf('/');
	int secLastSlashIdx = manifestFileURL.lastIndexOf('/', lastSlashIdx - 1);
	return manifestFileURL.substring(secLastSlashIdx + 1, lastSlashIdx);
}
 

@Override
public void activate(final Collection<SesameConnectedSegmentsMatch> matches) throws RepositoryException {
	final RepositoryConnection con = driver.getConnection();
	final ValueFactory vf = driver.getValueFactory();

	final URI connectsTo = vf.createURI(BASE_PREFIX + CONNECTS_TO);
	for (final SesameConnectedSegmentsMatch match : matches) {
		// delete segment2 by removing all (segment2, _, _) and (_, _, segment2) triples
		final RepositoryResult<Statement> outgoingEdges = con.getStatements(match.getSegment2(), null, null, true);
		while (outgoingEdges.hasNext()) {
			con.remove(outgoingEdges.next());
		}
		final RepositoryResult<Statement> incomingEdges = con.getStatements(null, null, match.getSegment2(), true);
		while (incomingEdges.hasNext()) {
			con.remove(incomingEdges.next());
		}

		// insert (segment1)-[:connectsTo]->(segment3) edge
		con.add(match.getSegment1(), connectsTo, match.getSegment3());
	}
}
 

@Override
public void activate(final Collection<SesameSwitchMonitoredMatch> matches) throws Exception {
	final RepositoryConnection con = driver.getConnection();
	final ValueFactory vf = driver.getValueFactory();

	final URI sensorEdgeType = vf.createURI(BASE_PREFIX + MONITORED_BY);
	final URI sensorType = vf.createURI(BASE_PREFIX + SENSOR);
	final URI trackElementType = vf.createURI(BASE_PREFIX + TRACKELEMENT);

	for (final SesameSwitchMonitoredMatch match : matches) {
		final Resource sw = match.getSw();

		final URI sensor = vf.createURI(BASE_PREFIX + ID_PREFIX + driver.generateNewVertexId());

		// set vertex type
		con.add(sensor, RDF.TYPE, sensorType);

		// insert the supertype as well
		if (!driver.isInferencing()) {
			con.add(sensor, RDF.TYPE, trackElementType);
		}

		// insert edge
		con.add(sw, sensorEdgeType, sensor);
	}
}
 

@Override
public void activate(final Collection<SesameSwitchSetMatch> matches) throws RepositoryException {
	final RepositoryConnection con = driver.getConnection();
	final ValueFactory vf = driver.getValueFactory();

	final URI currentPositionProperty = vf.createURI(BASE_PREFIX + CURRENTPOSITION);

	for (final SesameSwitchSetMatch match : matches) {
		final Resource sw = match.getSw();
		final Value position = match.getPosition();
		final Value currentPosition = match.getCurrentPosition();

		final RepositoryResult<Statement> statementsToRemove = con.getStatements(sw, currentPositionProperty, currentPosition, false);
		while (statementsToRemove.hasNext()) {
			con.remove(statementsToRemove.next());
		}

		con.add(sw, currentPositionProperty, position);
	}
}
 

@Override
public RepositoryConnection getConnection()
    throws RepositoryException
{
    if( isNotInitialized )
    {
        return null;
    }
    return repo.getConnection();
}
 

protected String exportRepository(RepositoryConnection connection) throws RepositoryException, RDFHandlerException {
	StringWriter writer=new StringWriter();
	RDFWriter rdfWriter=Rio.createWriter(getFormat(),writer);
	if(rdfWriter instanceof TurtleWriter) {
		rdfWriter=new RebasingTurtleWriter(writer);
	}
	connection.export(rdfWriter);
	return writer.toString();
}
 

private void closeConnection(RepositoryConnection cnx, String operation) {
    if (cnx != null) {
        try {
            cnx.close();
        } catch (RepositoryException x) {
            LOG.error("{}. Error closing repository connection: {}", operation, x.getMessage());
        }
    }
}
 

/**
 * Creates a new graph streaming output that executes a CONSTRUCT query
 * and streams the result.
 * 
 * @param query the CONSTRUCT query to execute
 * @param writerFactory a RDF writer factory to use for serialisation
 * @param conn the connection to use for query execution
 */
public SPARQLGraphStreamingOutput(
		GraphQuery query,
		RDFWriterFactory writerFactory,
		RepositoryConnection conn) {
	super(conn);
	this.query = query;
	this.factory = writerFactory;
}
 

private void executeQuery(final SailRepository repo)
		throws RepositoryException, MalformedQueryException,
		QueryEvaluationException, RDFParseException, IOException,
		RDFHandlerException {
	try {
		repo.initialize();
		final RepositoryConnection conn = repo.getConnection();
		conn.setAutoCommit(false);
		try {
			final ValueFactory vf = conn.getValueFactory();
			conn.add(vf.createURI("os:subject"), vf.createURI("os:prop"), vf.createLiteral("value"));
			conn.commit();

			String query = 
				"SELECT ?b { {} union { ?a ?b ?c } }"
				;
			
			TupleQuery tq = conn.prepareTupleQuery(QueryLanguage.SPARQL, query);
			TupleQueryResult tqr = tq.evaluate();
			assertTrue(tqr.hasNext());
			
			while (tqr.hasNext()) {
				System.err.println(tqr.next());
			}
			
			tqr.close();
		} finally {
			conn.close();
		}
	} finally {
		repo.shutDown();
	}
}