@Test
  public void testJSONFieldNameAsNull() throws Exception {
    String verifyString = null;
    String jsonString = "{name:null, age:14}";

    PdxInstanceImpl pi = (PdxInstanceImpl) JSONFormatter.fromJSON(jsonString);
    PdxString pdx = (PdxString) pi.getRawField("name");
    assertEquals(verifyString, pdx);
  }
this test verifies that pdxstream with pdxType.Object tyep for string and checks whether we
create PdxString or not
geode-core/src/integrationTest/java/org/apache/geode/pdx/PdxStringJUnitTest.java