@Test
    public void testMultiThreaded() throws Exception {
        int numThreads = 10;
        ExecutorService executorService = Executors.newFixedThreadPool(numThreads);
        ExecutorCompletionService<Integer> executorCompletionService =
                new ExecutorCompletionService<>(executorService);

        for (int i = 0; i < numThreads; i++) {
            executorCompletionService.submit(() -> {
                for (int i1 = 0; i1 < 10; i1++) {
                    List<Metadata> metadataList = getRecursiveMetadata("testODTEmbedded.odt");
                    assertEquals(3, metadataList.size());
                    assertEquals("THUMBNAIL",
                            metadataList.get(1).get(TikaCoreProperties.EMBEDDED_RESOURCE_TYPE));
                }
                return 1;
            });
        }

        try {
            int finished = 0;
            while (finished < numThreads) {
                Future<Integer> future = executorCompletionService.take();
                future.get();
                finished++;
            }
        } finally {
            executorService.shutdownNow();
        }
    }
Similar to {@link #testOO2()} )}, but using an OO3 file
tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-miscoffice-module/src/test/java/org/apache/tika/parser/odf/ODFParserTest.java