RESTfull Web服务和客户端设计

Question

Tech Stack : Java 1.6, JPA (Hibernate 3), Spring 3, Oracle 11g, JAX-RS (RESTEasy), Freemarker, Spring Webflow, jQuery, JBoss5

Hello,

Currently I am working on a project where we have two set of functionalities :

1. To publish a set of web services (RESTful) for external clients to consume.
2. To create a set of screens (around 10) which basically allows Admin functions to be performed eg create MI reports, set up new data, configuration and view past data.

My approach is to:

1. To create a service layer

2. Webflow and Freemarker templates invoking methods on this service layer.

3. And create another layer of components for REST (@Path), again using the same service layer.

Now in a design meeting someone suggested the following:

1. Seperate the layers in to seperate modules (as in maven)

2. Create a module each for:

   a2. RESTful services (with service layer and javax.ws.rs.Produces)

   b2. Screens with a service layer invloking the services published in module a2. This will use org.apache.commons.httpclient. HttpClient to invloke the a2 services.

I am not sure if I can really see the benefits or if this is the correct approach. I think maybe I don't undestand the suggested approach.

Can some one please elaborate as to which approach is better and why?

Thanks, adi

Answer 1

IMHO, this is not necessary to use the HttpClient and everything to access the service layer.

This mechanism will produce a huge and useless CPU overhead (serialize / fake the http transport / deserialize the message) to communicate between 2 layers that are very close (in the same war).

If you are sure the administration screens and the REST services will always be deployed together, use direct communication, stay pragmatic.

You should keep one maven project. There is no need to create a complex project for 10 screens and 5 REST services. Keep it simple.

Create a service layer that handles the business + bo. Create a transport layer with 2 separate implementations:

• one for the REST services directly calling the java classes from the service layer
• one for the administration, also directly calling the java classes from the service layer

If you really want to create maven module, - create one module that bundles the business services classes in a jar - create two modules that bundles the transports implementation in 2 separate jars - create one module that bundles the business services.jar, the two transport implementation.jar and their dependencies in a war

HIH