Examples with VisitorException org.eclipse.rdf4j.query.parser.serql.ast.VisitorException used on opensource projects

Example 1 with VisitorException

use of org.eclipse.rdf4j.query.parser.serql.ast.VisitorException in project rdf4j by eclipse.

the class ProjectionProcessor method visit.

@Override
public Object visit(ASTSelect selectNode, Object data) throws VisitorException {
    // Collect all variables used in the body of the select query
    Set<String> bodyVars = VariableCollector.process(selectNode.jjtGetParent());
    if (selectNode.isWildcard()) {
        // Make wildcard projection explicit
        for (String varName : bodyVars) {
            ASTProjectionElem projElemNode = new ASTProjectionElem(SyntaxTreeBuilderTreeConstants.JJTPROJECTIONELEM);
            selectNode.jjtAppendChild(projElemNode);
            projElemNode.jjtSetParent(selectNode);
            ASTVar varNode = new ASTVar(SyntaxTreeBuilderTreeConstants.JJTVAR);
            varNode.setName(varName);
            projElemNode.jjtAppendChild(varNode);
            varNode.jjtSetParent(projElemNode);
        }
        selectNode.setWildcard(false);
    } else {
        // Verify that all projection vars are bound
        Set<String> projVars = new LinkedHashSet<String>();
        for (ASTProjectionElem projElem : selectNode.getProjectionElemList()) {
            projVars.addAll(VariableCollector.process(projElem.getValueExpr()));
        }
        projVars.removeAll(bodyVars);
        if (!projVars.isEmpty()) {
            StringBuilder errMsg = new StringBuilder(64);
            errMsg.append("Unbound variable(s) in projection: ");
            Iterator<String> iter = projVars.iterator();
            while (iter.hasNext()) {
                errMsg.append(iter.next());
                if (iter.hasNext()) {
                    errMsg.append(", ");
                }
            }
            throw new VisitorException(errMsg.toString());
        }
    }
    return data;
}

Example 2 with VisitorException

use of org.eclipse.rdf4j.query.parser.serql.ast.VisitorException in project rdf4j by eclipse.

the class ProjectionAliasProcessor method visit.

@Override
public Object visit(ASTSelect node, Object data) throws VisitorException {
    // Iterate over all projection elements to retrieve the defined aliases
    Set<String> aliases = new HashSet<String>();
    List<Node> unaliasedNodes = new ArrayList<Node>();
    for (int i = 0; i < node.jjtGetNumChildren(); i++) {
        ASTProjectionElem projElem = (ASTProjectionElem) node.jjtGetChild(i);
        String alias = projElem.getAlias();
        if (alias == null && projElem.getValueExpr() instanceof ASTVar) {
            alias = ((ASTVar) projElem.getValueExpr()).getName();
        }
        if (alias != null) {
            boolean isUnique = aliases.add(alias);
            if (!isUnique) {
                throw new VisitorException("Duplicate projection element names: '" + alias + "'");
            }
        } else {
            unaliasedNodes.add(projElem);
        }
    }
    // Iterate over the unaliased nodes and generate aliases for them
    int aliasNo = 1;
    for (Node projElem : unaliasedNodes) {
        // Generate unique alias for projection element
        String alias;
        while (aliases.contains(alias = "_" + aliasNo++)) {
        // try again
        }
        aliases.add(alias);
        ASTString aliasNode = new ASTString(SyntaxTreeBuilderTreeConstants.JJTSTRING);
        aliasNode.setValue(alias);
        aliasNode.jjtSetParent(projElem);
        projElem.jjtAppendChild(aliasNode);
    }
    return data;
}

Example 3 with VisitorException

use of org.eclipse.rdf4j.query.parser.serql.ast.VisitorException in project rdf4j by eclipse.

the class NamespaceDeclProcessor method process.

/**
 * Processes prefix declarations in queries. This method collects all prefixes that are declared in the
 * supplied query, verifies that prefixes are not redefined and replaces any {@link ASTQName} nodes in the
 * query with equivalent {@link ASTIRI} nodes.
 *
 * @param qc
 *        The query that needs to be processed.
 * @return A map containing the prefixes that are declared in the query (key) and the namespace they map
 *         to (value).
 * @throws MalformedQueryException
 *         If the query contains redefined prefixes or qnames that use undefined prefixes.
 */
public static Map<String, String> process(ASTQueryContainer qc) throws MalformedQueryException {
    List<ASTNamespaceDecl> nsDeclList = qc.getNamespaceDeclList();
    // Build a prefix --> URI map
    Map<String, String> nsMap = new LinkedHashMap<String, String>();
    for (ASTNamespaceDecl nsDecl : nsDeclList) {
        String prefix = nsDecl.getPrefix();
        String uri = nsDecl.getURI().getValue();
        if (nsMap.containsKey(prefix)) {
            // Prefix already defined
            if (nsMap.get(prefix).equals(uri)) {
            // duplicate, ignore
            } else {
                throw new MalformedQueryException("Multiple namespace declarations for prefix '" + prefix + "'");
            }
        } else {
            nsMap.put(prefix, uri);
        }
    }
    // Use default namespace prefixes when not defined explicitly
    if (!nsMap.containsKey("rdf")) {
        nsMap.put("rdf", RDF.NAMESPACE);
    }
    if (!nsMap.containsKey("rdfs")) {
        nsMap.put("rdfs", RDFS.NAMESPACE);
    }
    if (!nsMap.containsKey("xsd")) {
        nsMap.put("xsd", XMLSchema.NAMESPACE);
    }
    if (!nsMap.containsKey("owl")) {
        nsMap.put("owl", OWL.NAMESPACE);
    }
    if (!nsMap.containsKey("sesame")) {
        nsMap.put("sesame", SESAME.NAMESPACE);
    }
    // For backwards compatibility:
    Map<String, String> extendedNsMap = new HashMap<String, String>(nsMap);
    if (!extendedNsMap.containsKey("serql")) {
        extendedNsMap.put("serql", SESAME.NAMESPACE);
    }
    // Replace all qnames with URIs
    QNameProcessor visitor = new QNameProcessor(extendedNsMap);
    try {
        qc.jjtAccept(visitor, null);
    } catch (VisitorException e) {
        throw new MalformedQueryException(e.getMessage(), e);
    }
    return nsMap;
}

Example 4 with VisitorException

use of org.eclipse.rdf4j.query.parser.serql.ast.VisitorException in project rdf4j by eclipse.

the class SeRQLParser method parseQuery.

public ParsedQuery parseQuery(String queryStr, String baseURI) throws MalformedQueryException {
    try {
        ASTQueryContainer qc = SyntaxTreeBuilder.parseQuery(queryStr);
        // Replace deprecated NULL nodes with semantically equivalent
        // alternatives
        NullProcessor.process(qc);
        StringEscapesProcessor.process(qc);
        Map<String, String> namespaces = NamespaceDeclProcessor.process(qc);
        ProjectionProcessor.process(qc);
        qc.jjtAccept(new ProjectionAliasProcessor(), null);
        qc.jjtAccept(new AnonymousVarGenerator(), null);
        // TODO: check use of unbound variables?
        TupleExpr tupleExpr = QueryModelBuilder.buildQueryModel(qc, SimpleValueFactory.getInstance());
        ASTQuery queryNode = qc.getQuery();
        ParsedQuery query;
        if (queryNode instanceof ASTTupleQuery) {
            query = new ParsedTupleQuery(tupleExpr);
        } else if (queryNode instanceof ASTGraphQuery) {
            query = new ParsedGraphQuery(tupleExpr, namespaces);
        } else {
            throw new RuntimeException("Unexpected query type: " + queryNode.getClass());
        }
        return query;
    } catch (ParseException e) {
        throw new MalformedQueryException(e.getMessage(), e);
    } catch (TokenMgrError e) {
        throw new MalformedQueryException(e.getMessage(), e);
    } catch (VisitorException e) {
        throw new MalformedQueryException(e.getMessage(), e);
    }
}