protected TrackingHandler process(String filename, ContainerExtractor extractor,
                                      boolean recurse) throws Exception {
        try (TikaInputStream stream = getTestFile(filename)) {
            assertEquals(true, extractor.isSupported(stream));

            // Process it
            TrackingHandler handler = new TrackingHandler();
            if (recurse) {
                extractor.extract(stream, extractor, handler);
            } else {
                extractor.extract(stream, null, handler);
            }

            // So they can check what happened
            return handler;
        }
    }
Parent class of tests that the various POI powered parsers are
able to extract their embedded contents.
tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-microsoft-module/src/test/java/org/apache/tika/parser/microsoft/AbstractPOIContainerExtractionTest.java