@Test
    public void unknownEmptyMessageField() throws Exception
    {
        JsonIOUtil.mergeFrom(UNKNOWN_EMPTY_MESSAGE_FIELD.getBytes(), instance, SCHEMA, false);
        checkKnownFields(instance);
    }
Test for ignoring unknown fields during de-seralization
protostuff-json/src/test/java/io/protostuff/JsonUnknownFieldTest.java