For RESTful services in Java, is JAX-RS better than an MVC framework like Swing, Grails or Play?

Question

For example, Play-framework supports RESTful services like this: RESTful on Play! framework

How does this compare to something like Jax-RS Jersey implementation? Does a framework like Play run circles around Jersey because of all it's cool bells and whistles, and it does REST too?

Developer productivity is important, but so is a proper implementation. Perhaps using an MVC framework for REST only services is 'wrong'?

Note, only RESTful services, no UI components at all.

Answer 1

Even though it's not "wrong" to use an MVC framework for RESTful services, there are some pros and cons versus using a JAX-RS implementation.

(Disclaimer: I have only used Jersey and Play! for fun, and not on production-grade systems, so I have tailored my comments more generally to MVC vs. JAX-RS. Keep in mind that these are broad generalizations.)

MVC frameworks--at least the ones that are considered developer friendly and "slick"--typically save you from having to build a persistence layer (the model part). Most also simplify "routing" requests using either scaffolding via convention or some form of configuration. The downsides are that you have to conform to some conventions for your controllers and usually have to write a view for each resource (or build layers of abstractions to avoid rewriting the same code).

JAX-RS excels at defining the routing (using Java annotations) as well as eliminating any restrictions on the service class. In my experience, that has greatly reduced the amount of boilerplate code and developer overhead. Jersey and Apache CXF also handle the XML or JSON serialization using JAXB annotations, which eliminates the need to figure out the view in an MVC context. The downside here is that you have to figure out your own ORM or persistence layer, which could be good or bad depending on whether you're building on top of existing data or creating a greenfield system (or using something other than an JPA/RDBMS e.g. NoSQL data store).

My own personal comment: Play! is a really cool framework, but I'd choose CXF (or Jersey) over an MVC framework any day for building out a RESTful service. In my experience, this frees up the developer to focus on the logic needed for the service, and opens up options for different database approaches. Right tool for the right job.