----- Original Message -----
Sent: Tuesday, June 17, 2003 12:56
PM
Subject: passing objects by reference
in SOAP - How would it work?
Hi
A typical SDK is object-oriented
and involves passing objects/data by
references (pointers). This will
work as long as the client using the SDK is
in the same address space of
the SDK. However, if client and SDK (i.e., the
service which provides SDK
functions) are in different address spaces, then
this will not work "AS
IS", and we need some kind of
marshalling/demarshalling mechanism used in
DCOM and CORBA etc.
How does such a thing will work in SOAP given the
fact that SOAP does NOT
support passing objects by
reference?
Consider the example of a typical SDK given
below:
Z, A, B, C, D and E are some classes. a, b, c, d and e are
instances of A,
B, C, D, E respectively. Classes Z, A, B, C, D and E have
various functions,
which could be used for various purposes. consider the
code below, which
shows how to use a function "getE" of class
E.
----------
A a = Z.getA(some parameters - p1) // getA is
static function
B b = a.getB(some parameters - p2)
C c =
b.getC(some parameters - p3)
D d = c.getD(some parameters -
p4)
E e = d.getE(some parameters - p5)
---------
Now if
I wish to expose such a SDK as a WebService, then I cann't do this
"as
is" because SOAP does not support passing objects by references. Thus,
I
cannot expose "getA" function as WebService, as it returns instance of
class
A, which inturn has functions (executed at service side), which
return other
objects (like b)
Thus AFAIK, the only way out is to
expose a single function "getE", which in
turn will do all the stuff,
i.e.,
getE(p1, p2, p3, p4, p5) {
A a = Z.getA(p1) // getA is
static function
B b = a.getB(p2)
C c = b.getC( p3)
D d
= c.getD(p4)
E e = d.getE(p5)
return e;
}
Is
there a better way out? Or this is the only way to expose such
existing
SDKs as Web Services?
thanks & regards,
Naresh
Agarwal
