What are the specifications/recommendations for data types in JAX-RPC web services?

When developing a web service using Java, Axis1 and JAX-RPC, what are the constraints, recommendations and specifications that mu开发者_JS百科st be followed when sending complex data types over a web service?

For example, the method:
public MyComplexClass webServiceOperation() {
  return new MyComplexClass;
}

Is there any limitation on the methods, getters, setters, variables, etc for MyComplexClass?

I suggest you to check this excellent article

http://www.ibm.com/developerworks/webservices/library/ws-tip-jaxwsrpc/

and this

http://www.nesc.ac.uk/talks/ahm2006/621.ppt‎