How to design a client object???

Question

hello,Michael Wooten
thank for your help, now I know the list of Java data types for the parameters
and return values, and their corresponding SOAP data types.
but how to design a client object, f.e: this object is value Object in ejb, their
have some gets and sets methods, these set methods, their return type is void
in java, but now in web service,how to deal with these prolem?
like ejb, we have ejb's design pattern, for web service, do we have their design
pattern also?
thanks :-)

Answer 1

Hi littlehill,
In general, you want to think of the input parameters (and return values) for
a web service method as "hierarchical state", not objects :-)
The main motivation for taking this approach is to reduce the likelihood of interoperability
issues with other (noteably non-Java) SOAP packages. The JavaBean model provides
a simple, easy to implement mechanism for creating "hierarchical state", because
it allows nesting. Using this nested JavaBean approach, you should be able to
create an object graph that represents your "value object", but again the key
here is to not thinking of them (the value objects) as objects, but state ;-)
Each SOAP (or Web Services) toolkit will have a different approach and API for
writing SOAP clients, unless it supports JAX-RPC. This being the case, it is a
bit difficult to come up with an "across the board" design for a web service client
;-) In the case of Java-based SOAP toolkits, most developers prefer to "stay in
the object world" as opposed to dealing with XML parsing APIs. To accommodate
this desire, most Java-based SOAP toolkits have a "XML-to-Java, Java-to-XML" type
mapping mechanism to handle the complexities of this task. If you don't want to
muck around with type mappings, you should look around for a product that can
generate Java classes from XML Schema, and vis-versa. WLS 7.0 does a better good
of this than WLS 6.1, so you might want to check it out. I've also had a fair
amount of success with the Exolab Castor data binding package (http://castor.exolab.org/sourcegen.html).
It has a very comprehensive implementation of "XML Schema Part 1: Structures"
and "XML Schema Part 2: Datatypes", is open-source, and works quite well. When
you get down to it, a good XML Schema processor is key to saving yourself lots
of frustration and coding.
Regards,
Mike Wooten
"littlehill lee" <[email protected]> wrote:
>
hello,Michael Wooten
thank for your help, now I know the list of Java data types for the parameters
and return values, and their corresponding SOAP data types.
but how to design a client object, f.e: this object is value Object in
ejb, their
have some gets and sets methods, these set methods, their return type
is void
in java, but now in web service,how to deal with these prolem?
like ejb, we have ejb's design pattern, for web service, do we have their
design
pattern also?
thanks :-)