Examples with QueryExecException org.apache.jena.query.QueryExecException used on opensource projects

Example 6 with QueryExecException

use of org.apache.jena.query.QueryExecException in project jena by apache.

the class QueryExecDataset method execJson.

@Override
public JsonArray execJson() {
    checkNotClosed();
    if (!query.isJsonType())
        throw new QueryExecException("Attempt to get a JSON result from a " + labelForQuery(query) + " query");
    startQueryIterator();
    JsonArray jsonArray = new JsonArray();
    List<String> resultVars = query.getResultVars();
    while (queryIterator.hasNext()) {
        Binding binding = queryIterator.next();
        JsonObject jsonObject = new JsonObject();
        for (String resultVar : resultVars) {
            Node n = binding.get(Var.alloc(resultVar));
            JsonValue value = RDFTerm2Json.fromNode(n);
            jsonObject.put(resultVar, value);
        }
        jsonArray.add(jsonObject);
    }
    return jsonArray;
}

Example 7 with QueryExecException

use of org.apache.jena.query.QueryExecException in project jena by apache.

the class QueryExecDataset method describe.

// -- Describe
@Override
public Graph describe(Graph graph) {
    checkNotClosed();
    Model model = ModelFactory.createModelForGraph(graph);
    if (!query.isDescribeType())
        throw new QueryExecException("Attempt to get a DESCRIBE result from a " + labelForQuery(query) + " query");
    query.setResultVars();
    // columns).
    if (query.getQueryPattern() == null)
        query.setQueryPattern(new ElementGroup());
    Set<Node> set = new HashSet<>();
    RowSet rows = execute();
    // Prefixes for result (after initialization)
    insertPrefixesInto(graph);
    // Variables in DESCRIBE
    if (rows != null) {
        // Single pass over rows.
        rows.forEachRemaining(row -> {
            for (Var var : rows.getResultVars()) {
                Node n = row.get(var);
                if (n != null)
                    set.add(n);
            }
        });
    }
    // Any URIs in the DESCRIBE
    if (query.getResultURIs() != null) {
        query.getResultURIs().forEach(set::add);
    }
    // DescribeHandlers work on models.
    // Create new handlers for this process.
    List<DescribeHandler> dhList = DescribeHandlerRegistry.get().newHandlerList();
    getContext().put(ARQConstants.sysCurrentDataset, getDataset());
    // Notify start of describe phase
    for (DescribeHandler dh : dhList) dh.start(model, getContext());
    // Do describe for each resource found.
    for (Node n : set) {
        RDFNode rdfNode = ModelUtils.convertGraphNodeToRDFNode(n, model);
        if (rdfNode instanceof Resource) {
            for (DescribeHandler dh : dhList) {
                dh.describe((Resource) rdfNode);
            }
        } else {
            // Can't describe literals
            continue;
        }
    }
    for (DescribeHandler dh : dhList) dh.finish();
    this.close();
    return graph;
}

Example 8 with QueryExecException

use of org.apache.jena.query.QueryExecException in project jena by apache.

the class QueryExecDataset method execJsonItems.

@Override
public Iterator<JsonObject> execJsonItems() {
    checkNotClosed();
    if (!query.isJsonType())
        throw new QueryExecException("Attempt to get a JSON result from a " + labelForQuery(query) + " query");
    startQueryIterator();
    return new JsonIterator(queryIterator, query.getResultVars());
}

Example 9 with QueryExecException

use of org.apache.jena.query.QueryExecException in project jena by apache.

the class TextQueryPF method exec.

@Override
public QueryIterator exec(Binding binding, PropFuncArg argSubject, Node predicate, PropFuncArg argObject, ExecutionContext execCxt) {
    if (log.isTraceEnabled()) {
        IndentedLineBuffer subjBuff = new IndentedLineBuffer();
        argSubject.output(subjBuff, null);
        IndentedLineBuffer objBuff = new IndentedLineBuffer();
        argObject.output(objBuff, null);
        log.trace("exec: {} text:query {}", subjBuff, objBuff);
    }
    if (textIndex == null) {
        if (!warningIssued) {
            Log.warn(getClass(), "No text index - no text search performed");
            warningIssued = true;
        }
        // Not a text dataset - no-op
        return IterLib.result(binding, execCxt);
    }
    argSubject = Substitute.substitute(argSubject, binding);
    argObject = Substitute.substitute(argObject, binding);
    Node s = null;
    Node score = null;
    Node literal = null;
    Node graph = null;
    Node prop = null;
    if (argSubject.isList()) {
        // Length checked in build()
        s = argSubject.getArg(0);
        if (argSubject.getArgListSize() > 1) {
            score = argSubject.getArg(1);
            if (!score.isVariable())
                throw new QueryExecException("Hit score is not a variable: " + argSubject);
        }
        if (argSubject.getArgListSize() > 2) {
            literal = argSubject.getArg(2);
            if (!literal.isVariable())
                throw new QueryExecException("Hit literal is not a variable: " + argSubject);
        }
        if (argSubject.getArgListSize() > 3) {
            graph = argSubject.getArg(3);
            if (!graph.isVariable())
                throw new QueryExecException("Hit graph is not a variable: " + argSubject);
        }
        if (argSubject.getArgListSize() > 4) {
            prop = argSubject.getArg(4);
            if (!prop.isVariable())
                throw new QueryExecException("Hit prop is not a variable: " + argSubject);
        }
    } else {
        s = argSubject.getArg();
    }
    if (s.isLiteral())
        // Does not match
        return IterLib.noResults(execCxt);
    StrMatch match = objectToStruct(argObject, true);
    if (match == null) {
        // can't match
        return IterLib.noResults(execCxt);
    }
    QueryIterator qIter = prepareQuery(binding, s, score, literal, graph, prop, match, execCxt);
    if (match.getLimit() >= 0)
        qIter = new QueryIterSlice(qIter, 0, match.getLimit(), execCxt);
    return qIter;
}

Example 10 with QueryExecException

use of org.apache.jena.query.QueryExecException in project jena by apache.

the class Service method exec.

/**
     * Executes a service operator
     * 
     * @param op
     *            Service
     * @param context
     *            Context
     * @return Query iterator of service results
     */
public static QueryIterator exec(OpService op, Context context) {
    if (context != null && context.isFalse(serviceAllowed))
        throw new QueryExecException("SERVICE execution disabled");
    if (!op.getService().isURI())
        throw new QueryExecException("Service URI not bound: " + op.getService());
    // This relies on the observation that the query was originally correct,
    // so reversing the scope renaming is safe (it merely restores the
    // algebra expression).
    // Any variables that reappear should be internal ones that were hidden
    // by renaming in the first place.
    // Any substitution is also safe because it replaced variables by
    // values.
    Op opRemote = Rename.reverseVarRename(op.getSubOp(), true);
    // JENA-494 There is a bug here that the renaming means that if this is
    // deeply nested and joined to other things at the same level of you end
    // up with the variables being disjoint and the same results
    // The naive fix for this is to map the variables visible in the inner
    // operator to those visible in the rewritten operator
    // There may be some cases where the re-mapping is incorrect due to
    // deeply nested SERVICE clauses
    Map<Var, Var> varMapping = new HashMap<>();
    Set<Var> originalVars = OpVars.visibleVars(op);
    Set<Var> remoteVars = OpVars.visibleVars(opRemote);
    boolean requiresRemapping = false;
    for (Var v : originalVars) {
        if (v.getName().contains("/")) {
            // A variable which was scope renamed so has a different name
            String origName = v.getName().substring(v.getName().lastIndexOf('/') + 1);
            Var remoteVar = Var.alloc(origName);
            if (remoteVars.contains(remoteVar)) {
                varMapping.put(remoteVar, v);
                requiresRemapping = true;
            }
        } else {
            // A variable which does not have a different name
            if (remoteVars.contains(v))
                varMapping.put(v, v);
        }
    }
    // Explain.explain("HTTP", opRemote, context) ;
    Query query;
    //@formatter:off
    // Comment (for the future?)
    //        if ( false )
    //        {
    //            // ***** Interacts with substitution.
    //            Element el = op.getServiceElement().getElement() ;
    //            if ( el instanceof ElementSubQuery )
    //                query = ((ElementSubQuery)el).getQuery() ;
    //            else
    //            {
    //                query = QueryFactory.create() ;
    //                query.setQueryPattern(el) ;
    //                query.setResultVars() ;
    //            }
    //        }
    //        else
    //@formatter:on
    query = OpAsQuery.asQuery(opRemote);
    Explain.explain("HTTP", query, context);
    String uri = op.getService().getURI();
    HttpQuery httpQuery = configureQuery(uri, context, query);
    InputStream in = httpQuery.exec();
    // Read the whole of the results now.
    // Avoids the problems with calling back into the same system e.g.
    // Fuseki+SERVICE <http://localhost:3030/...>
    ResultSet rs = ResultSetFactory.fromXML(in);
    QueryIterator qIter = QueryIter.materialize(new QueryIteratorResultSet(rs));
    // And close connection now, not when qIter is closed.
    IO.close(in);
    // nested SERVICE clauses
    if (requiresRemapping) {
        qIter = QueryIter.map(qIter, varMapping);
    }
    return qIter;
}