Examples with Group org.openrdf.query.algebra.Group used on opensource projects

Example 1 with Group

use of org.openrdf.query.algebra.Group in project incubator-rya by apache.

the class TopologyFactory method build.

@Override
public TopologyBuilder build(final String sparqlQuery, final String statementsTopic, final String resultsTopic, final BNodeIdFactory bNodeIdFactory) throws MalformedQueryException, TopologyBuilderException {
    requireNonNull(sparqlQuery);
    requireNonNull(statementsTopic);
    requireNonNull(resultsTopic);
    final ParsedQuery parsedQuery = new SPARQLParser().parseQuery(sparqlQuery, null);
    final TopologyBuilder builder = new TopologyBuilder();
    final TupleExpr expr = parsedQuery.getTupleExpr();
    final QueryVisitor visitor = new QueryVisitor(bNodeIdFactory);
    expr.visit(visitor);
    processorEntryList = visitor.getProcessorEntryList();
    final Map<TupleExpr, String> idMap = visitor.getIDs();
    // add source node
    builder.addSource(SOURCE, new StringDeserializer(), new VisibilityStatementDeserializer(), statementsTopic);
    // processing the processor entry list in reverse order means we go from leaf
    // nodes -> parent nodes.
    // So, when the parent processing nodes get added, the upstream
    // processing node will already exist.
    ProcessorEntry entry = null;
    for (int ii = processorEntryList.size() - 1; ii >= 0; ii--) {
        entry = processorEntryList.get(ii);
        // statement patterns need to be connected to the Source.
        if (entry.getNode() instanceof StatementPattern) {
            builder.addProcessor(entry.getID(), entry.getSupplier(), SOURCE);
        } else {
            final List<TupleExpr> parents = entry.getUpstreamNodes();
            final String[] parentIDs = new String[parents.size()];
            for (int id = 0; id < parents.size(); id++) {
                parentIDs[id] = idMap.get(parents.get(id));
            }
            builder.addProcessor(entry.getID(), entry.getSupplier(), parentIDs);
        }
        // Add a state store for any node type that requires one.
        if (entry.getNode() instanceof Join || entry.getNode() instanceof LeftJoin || entry.getNode() instanceof Group) {
            // Add a state store for the join processor.
            final StateStoreSupplier joinStoreSupplier = Stores.create(entry.getID()).withStringKeys().withValues(new VisibilityBindingSetSerde()).persistent().build();
            builder.addStateStore(joinStoreSupplier, entry.getID());
        }
    }
    // Add a formatter that converts the ProcessorResults into the output format.
    final SinkEntry<?, ?> sinkEntry = visitor.getSinkEntry();
    builder.addProcessor("OUTPUT_FORMATTER", sinkEntry.getFormatterSupplier(), entry.getID());
    // Add the sink.
    builder.addSink(SINK, resultsTopic, sinkEntry.getKeySerializer(), sinkEntry.getValueSerializer(), "OUTPUT_FORMATTER");
    return builder;
}