--
Stefan Tilkov, http://www.innoq.com/blog/st/
On Apr 19, 2007, at 8:21 PM, Marc Hadley wrote:
> See:
>
> https://jsr311.dev.java.net/sketches/sketch2/overview-summary.html
>
> I started with the previous sketch[1] and switched it to use a  
> builder pattern for responses as originally suggested by Dhanji,  
> handling of input data is the same for both. Here's a brief list of  
> the changes:
>
> - Coalesced the SPI packages into a single new package
> - Removed Representation<T> and JAXBRepresentation
> - Made Response into an abstract builder class, removed subclasses  
> (TemporaryRedirect etc) and moved it to the core package (no longer  
> any separate response package)
> - Removed annotations that are no longer needed (@HttpStatus,  
> @EntityBody)
> - Removed response header stuff from HttpHeaders
>
> For comparison, here are a few examples that show the two  
> approaches in action.
>
> (i) Method that returns a statically-typed entity using default  
> status (200 OK).
>
> @HttpMethod
> @ProduceMime("application/widgets+xml")
> Widget getWidget() {
>   Widget w = ...
>   return w;
> }
>
> The above works using either approach.
>
> (ii) Method that returns a dynamically-typed entity using default  
> status
>
> // annotation driven
> @HttpMethod
> Representation getWidget() {
>   Widget w = ...
>   return new Representation<Widget>(w, "application/widgets+xml");
> }
>
> // using builder
> @HttpMethod
> Response getWidget() {
>   Widget w = ...
>   return Response.representation(w, "application/widgets+xml");
> }
>
> (iii) Method that creates a new statically-typed resource and  
> returns a representation of it
>
> // annotation driven
> @HttpMethod("POST")
> @ProduceMime("application/widgets+xml")
> Response addWidget(...) {
>   Widget w = ...
>   URI widgetId = ...
>   Representation<Widget> r = new Representation<Widget>(w,  
> "application/widgets+xml");
>   return new Created(r, widgetId);
> }
>
> // using builder
> @HttpMethod("POST")
> @ProduceMime("application/widgets+xml")
> Response addWidget(...) {
>   Widget w = ...
>   URI widgetId = ...
>   return Response.created(w, widgetId);
> }
>
> (iv) Method that creates a new dynamically-typed resource and  
> returns a representation of it
>
> // annotation driven
> @HttpMethod("POST")
> Response addWidget(...) {
>   Widget w = ...
>   URI widgetId = ...
>   Representation<Widget> r = new Representation<Widget>(w,  
> "application/widgets+xml");
>   return new Created(r, widgetId);
> }
>
> // using builder
> @HttpMethod("POST")
> Response addWidget(...) {
>   Widget w = ...
>   URI widgetId = ...
>   return Response.created(w, widgetId).type("application/widgets 
> +xml");
> }
>
> Note that, for the examples above, the differences from a user  
> perspective between our initial proposal and sketch 1 are pretty  
> minimal, the impact on an implementation is the main difference as  
> outlined in an earlier mail[2].
>
> Having played with it a little I think I prefer the builder  
> approach, its very flexible for fine tuning a response and the  
> static methods of Response maintain the simplicity of creating a  
> particular kind of response that contains all the necessary metadata.
>
> Marc.
>
> [1] https://jsr311.dev.java.net/servlets/ReadMsg?list=dev&msgNo=233
> [2] https://jsr311.dev.java.net/servlets/ReadMsg?list=dev&msgNo=253
>
> ---
> Marc Hadley <marc.hadley at sun.com>
> CTO Office, Sun Microsystems.
>
>