code: @Override
      public void readFragmentFrom(MwsReader r) {
          nextToken = r.read("NextToken", String.class);
          amazonOrderId = r.read("AmazonOrderId", String.class);
          orderItems = r.readList("OrderItems", "OrderItem", OrderItem.class);
      }
docs: Read members from a MwsReader.
  
  @param r
  The reader to read from.