Reading material

[jcvanvorst]

While I've been developing J2EE apps for quite a while, I have yet to build a WS-based one, so I've decided to write one. In this vein, can anyone recommend a few decent books on the subject? (In addition to the references listed on the Spring-WS page)

I ask here because my intuitive sense of developing web services seems to mesh with the approach of Spring-WS. I have been reading through the airline and echo samples, but feel there are a few too many moving parts to get a complete grasp of developing a full app (wsdl, security, binding, faults, etc.).

Any guidance would be appreciated.

[Arjen Poutsma]

I ask here because my intuitive sense of developing web services seems to mesh with the approach of Spring-WS.

That's an interesting statement . Can you elaborate a bit?

I have been reading through the airline and echo samples, but feel there are a few too many moving parts to get a complete grasp of developing a full app (wsdl, security, binding, faults, etc.).

I'll admit that it can be a bit complex, but that's mostly because of the underlying technologies used. SOAP, for instance, isn't a remoting protocol like RMI or Hessian, but an XML messaging protocol. Of course you could try to make it look like an RPC protocol, but that means that you are creating an abstraction which turns out to be quite leaky.

The same goes for XML schemas: XSD and Java are two different things. It's the Impedance mismatch all over again. This doesn't mean that it's impossible to convert XML to objects, it just means that you should know what you're doing, just like using Hibernate.

Overall, SOAP, WSDL, WS-Security are not simple technologies, but I try to make it as simple as possible without loosing any of the expressive power.

As a result of all the WS-* complexity, some people prefer a REST model. With REST, you basically just send Plain Old XML (POX) across the wire. No WSDL, no SOAP, plain HTTP security. Currently, I'm looking into adding REST support to SWS before the 1.0-m2 release. Perhaps that would be more to your liking?

Cheers,

[jcvanvorst]

That's an interesting statement . Can you elaborate a bit?

Having just a big-picture view of WS, the RPC style I so often see never sat well with me. Much like you wrote in your blog, the primary concept in web-services is the XML that gets shuttled around. Starting the process there makes sense, just like starting with objects is the start of the domain (as opposed to starting with designing DB tables).

Overall, SOAP, WSDL, WS-Security are not simple technologies, but I try to make it as simple as possible without loosing any of the expressive power.

Agreed. I didn't mean for my comment to imply the samples or Spring-WS were too complex, just that it was difficult for me to, in essence, learn webservices via looking at the code. Its hard to know what's the "right" way to do something, and with things like security, ignorance can be dangerous. Basically, I was looking for a developer-level coverage of WS tech. For now, I'll just keep pushing through the refs.