@Test
  public void testStringJsonUnmarshaller() throws Exception {

    StringWriter sw = new StringWriter();
    AwsJsonWriter jw = JsonUtils.getJsonWriter(sw);
    jw.beginObject();
    jw.name("s");
    jw.value("String");
    jw.endObject();
    String json = sw.toString();

    StringReader sr = new StringReader(json);
    AwsJsonReader jr = JsonUtils.getJsonReader(sr);
    JsonUnmarshallerContext context = new JsonUnmarshallerContext(jr);
    context.getReader().beginObject();
    context.getReader().nextName();

    SimpleTypeJsonUnmarshallers.StringJsonUnmarshaller sUnmarshaller =
        SimpleTypeJsonUnmarshallers.StringJsonUnmarshaller.getInstance();
    assertEquals(sUnmarshaller.unmarshall(context), "String");
  }