@Override protected T nextImpl() throws IOException { String encodedElementString = encodedElements.get(nextIndex++); // TODO: Replace with the real encoding used by the // front end, when we know what it is. byte[] encodedElement = StringUtils.jsonStringToByteArray(encodedElementString); notifyElementRead(encodedElement.length); return CoderUtils.decodeFromByteArray(coder, encodedElement); }