Java Web Services in a Nutshell

Programming with JAX-RPC

Now that you’ve seen a simple example of JAX-RPC programming, this section lifts the hood a little and looks more closely at some of the details that were skimmed over in the first part of this chapter. Although much of what follows is completely generic, it isn’t possible to give a complete description of JAX-RPC programming without going beyond the bounds of the specification, since there are certain aspects of the programming model that vendors are permitted to implement in any convenient manner. Where this is the case, we’ll make it clear that what is being described is not covered by the specification, and we’ll use the JAX-RPC reference implementations in the J2EE 1.4 platform and the JWSDP as typical examples.

The JAX-RPC Service Interface

Web service development with JAX-RPC begins either with the definition of the service itself as a Java interface or by importing a service definition in the form of a WSDL document. In this chapter, for the sake of simplicity, we consider only the first case and defer discussion of WSDL and of using WSDL as the starting point for JAX-RPC development to Chapter 5 and Chapter 6, respectively. As noted earlier, using Java to define the service endpoint interface is not sufficient if you want to publish the service so that it can be used by clients written in other programming languages. In order to be truly open, the service definition has to be exported as a WSDL document. However, using Java as the definition language ...