@Test
    void simpleTest() throws ParserConfigurationException, SAXException, IOException, FastInfosetException {

        final SAXParserFactory factory = SAXParserFactory.newInstance();
        factory.setNamespaceAware(true);
        final SAXParser saxParser = factory.newSAXParser();

        ByteArrayOutputStream os;
        try (final Reader reader = new StringReader(XML_1)) {
            try (final ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream()) {
                os = byteArrayOutputStream;
                final SAXDocumentSerializer saxDocumentSerializer = new SAXDocumentSerializer();
                saxDocumentSerializer.setOutputStream(byteArrayOutputStream);
                saxParser.parse(new InputSource(reader), saxDocumentSerializer);
            }
        }

        final byte[] fastInfosetBytes = os.toByteArray();

        LOGGER.info("xml bytes len: {}", XML_1.getBytes().length);
        LOGGER.info("ser bytes len: {}", fastInfosetBytes.length);

        final SAXDocumentParser saxDocumentParser = new SAXDocumentParser();
        saxDocumentParser.setContentHandler(new LoggingHandler());
        //private static class LoggingHandler extends DefaultHandler {

        try (final ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(fastInfosetBytes)) {
            saxDocumentParser.parse(byteArrayInputStream);
        }
    }
A proof of concept for https://github.com/gchq/stroom/issues/1945
Trying to prove that we can generate a fast infoset vocab
for some xml and then append to it. This is to reduce the volume of data
stored in the LMDB ref data store.
stroom-pipeline/src/test/java/stroom/pipeline/refdata/TestFastInfosetVocab.java