This figure illustrates database call out. The following points describe the illustration.

• SQL and PL/SQL call specs—Invoke a Web service through a user-defined function call (generated through JPublisher) either directly within a SQL statement or view or through a variable.

• Pure Java static proxy class—Use JPublisher to pre-generate a client proxy class. which uses JAX-RPC. This method simplifies the Web service invocation as the location of the service is already known without needing to look up the service in the UDDI registry. The client proxy class does all of the work to construct the SOAP request, including marshalling and unmarshalling parameters.

• Pure Java using DII (dynamic invocation interface) over JAX-RPC—Dynamic invocation provides the ability to construct the SOAP request and access the service without the client proxy.