Java Class to Service IO Mapper

We�re building an adapter service template, where u are able to select an object(java) from some proprietary java api and have it�s keys set as inputs to the service and properties exposed as outputs from the service.

Now is there an easy way to do this mapping or am I gonna have to build this manually using introspection.

In short is there some sort of Java Class to Document mapper or something?

Any ideas?