Access to Backend

Hi,

We are planning to work with Webdynpro for Java. What is the best approach to retrieve data from Oracle as back end system. We have JavaBean model and Adaptive Webservice model. I have gone through some tutorials where in an EJB can be exposed as Webservice and can be used in Webdynpro as Adaptive Webservice model.

Can any one please suggest what are the advantages and disadvantages of using Java bean model or Webservice model.

Thanks,

Portal