@Test()
  public void shouldAllowNullInFieldValue() throws Exception {
    Map<String, Analyzer> fields = new HashMap<>();
    fields.put("field1", null);
    fields.put("field2", null);
    region = createRegionAndIndex(fields);

    // Put two values with some of the same tokens
    String value1 = "one three";
    region.put("A", new TestObject(value1, null));
    luceneService.waitUntilFlushed(INDEX_NAME, REGION_NAME, 60000, TimeUnit.MILLISECONDS);

    verifyQuery("field1:one", DEFAULT_FIELD, "A");
  }
This class contains tests of lucene queries that can fit
geode-lucene/src/integrationTest/java/org/apache/geode/cache/lucene/LuceneQueriesIntegrationTest.java