Re: [Jersey] Jersey's (experimental) approach to support hypermedia constraint

From: Jan Algermissen <>
Date: Wed, 10 Feb 2010 20:38:26 +0100

On Feb 10, 2010, at 6:40 PM, Paul Sandoz wrote:

> Although as you say there are no guarantees there are good probabilities that a documented service will not break clients by removing documented features e.g. a link, of the payment type, MUST be present in the representation for application/order+xml. Hence there may be value coding for the probably case and managing errors with exceptions.

If the server sends a representation that does not conform to the corresponding specs (e.g. missing mandatory element) then that is surely an error on the server side and clients should handle that as an error condition.

What I am talking about is that the server cannot be constrained to send a particular media type (let alone Link headers). It might send application/order+xml for two years and the next day start to send an HTML representation of the order. Client side APIs should IMHO emphasize this and enforce proper client side implementation instead of leading client developers to think they can make any kind of assumption whatsoever.


 Jan Algermissen, Consultant
 NORD Software Consulting