Examples with StreamingTransform nux.xom.xquery.StreamingTransform used on opensource projects

Example 1 with StreamingTransform

use of nux.xom.xquery.StreamingTransform in project teiid by teiid.

the class XQueryEvaluator method evaluateXQuery.

public static SaxonXQueryExpression.Result evaluateXQuery(final SaxonXQueryExpression xquery, Object context, Map<String, Object> parameterValues, final RowProcessor processor, CommandContext commandContext) throws TeiidProcessingException, TeiidComponentException {
    DynamicQueryContext dynamicContext = new DynamicQueryContext(xquery.config);
    SaxonXQueryExpression.Result result = new SaxonXQueryExpression.Result();
    try {
        for (Map.Entry<String, Object> entry : parameterValues.entrySet()) {
            try {
                Object value = entry.getValue();
                Sequence s = null;
                if (value instanceof SQLXML) {
                    value = XMLSystemFunctions.convertToSource(value);
                    result.sources.add((Source) value);
                    Source source = wrapStax((Source) value);
                    s = xquery.config.buildDocumentTree(source).getRootNode();
                } else if (value instanceof java.util.Date) {
                    s = XQueryEvaluator.convertToAtomicValue(value);
                } else if (value instanceof BinaryType) {
                    s = new HexBinaryValue(((BinaryType) value).getBytesDirect());
                }
                dynamicContext.setParameter(StructuredQName.fromClarkName(entry.getKey()), s);
            } catch (TransformerException e) {
                throw new TeiidProcessingException(QueryPlugin.Event.TEIID30148, e, QueryPlugin.Util.gs(QueryPlugin.Event.TEIID30148, entry.getKey()));
            }
        }
        if (context != null) {
            Source source = XMLSystemFunctions.convertToSource(context);
            result.sources.add(source);
            source = wrapStax(source);
            if (xquery.contextRoot != null) {
                // create our own filter as this logic is not provided in the free saxon
                AugmentedSource sourceInput = AugmentedSource.makeAugmentedSource(source);
                sourceInput.addFilter(new FilterFactory() {

                    @Override
                    public ProxyReceiver makeFilter(Receiver arg0) {
                        return new PathMapFilter(xquery.contextRoot, arg0);
                    }
                });
                source = sourceInput;
                // use streamable processing instead
                if (xquery.streamingPath != null && processor != null) {
                    if (LogManager.isMessageToBeRecorded(LogConstants.CTX_DQP, MessageLevel.DETAIL)) {
                        // $NON-NLS-1$
                        LogManager.logDetail(LogConstants.CTX_DQP, "Using stream processing for evaluation of", xquery.xQueryString);
                    }
                    // set to non-blocking in case default expression evaluation blocks
                    boolean isNonBlocking = commandContext.isNonBlocking();
                    commandContext.setNonBlocking(true);
                    final StreamingTransform myTransform = new StreamingTransform() {

                        public Nodes transform(Element elem) {
                            processor.processRow(XQueryEvaluator.wrap(elem, xquery.config));
                            return NONE;
                        }
                    };
                    Builder builder = new Builder(new SaxonReader(xquery.config, sourceInput), false, new StreamingPathFilter(xquery.streamingPath, xquery.namespaceMap).createNodeFactory(null, myTransform));
                    try {
                        // the builder is hard wired to parse the source, but the api will throw an exception if the stream is null
                        builder.build(FAKE_IS);
                        return result;
                    } catch (ParsingException e) {
                        if (e.getCause() instanceof TeiidRuntimeException) {
                            RelationalNode.unwrapException((TeiidRuntimeException) e.getCause());
                        }
                        throw new TeiidProcessingException(QueryPlugin.Event.TEIID30151, e, QueryPlugin.Util.gs(QueryPlugin.Event.TEIID30151));
                    } catch (IOException e) {
                        throw new TeiidProcessingException(QueryPlugin.Event.TEIID30151, e, QueryPlugin.Util.gs(QueryPlugin.Event.TEIID30151));
                    } finally {
                        if (!isNonBlocking) {
                            commandContext.setNonBlocking(false);
                        }
                    }
                }
            }
            TreeInfo doc;
            try {
                doc = xquery.config.buildDocumentTree(source);
            } catch (XPathException e) {
                throw new TeiidProcessingException(QueryPlugin.Event.TEIID30151, e, QueryPlugin.Util.gs(QueryPlugin.Event.TEIID30151));
            }
            dynamicContext.setContextItem(doc.getRootNode());
        }
        try {
            result.iter = xquery.xQuery.iterator(dynamicContext);
            return result;
        } catch (TransformerException e) {
            throw new TeiidProcessingException(QueryPlugin.Event.TEIID30152, e, QueryPlugin.Util.gs(QueryPlugin.Event.TEIID30152));
        }
    } finally {
        if (result.iter == null) {
            result.close();
        }
    }
}