CORBA clients - EJBs in WLS

Question

This is the situation we have:
1) We must support both C++ and Java clients that will be requesting
services from our EJBs running in WLS. The clients are internal apps running
in different companies and we would prefer to avoid requiring our clients to
use an ORB by a specific vendor. At the same time we do not want to deal
with potential problems related to the implementation differences by
different ORB vendors. What would be the best way to handle this situation?
2) WLS documentation has the following paragraph:
"WebLogic RMI over IIOP is the framework for EJB-to-CORBA mapping support.
Currently, however, a standard for passing user identity -- required to
implement EJB-to-CORBA mapping -- does not exist and the requirement for
transaction propagation from the client is in question. While RMI over IIOP
does allow CORBA clients to access EJBeans, the following services will not
be available:
EJB transaction services
EJB security services"
Does this mean that:
2.1) CORBA client initiated transactions will not be supported,
everything will work
2.2) None of the EJB security services will be available in EJB method
called by a CORBA client (i.e. getCallerPrincipal() and isCallerInRole()
will fail)
Thanks in advance

Answer 1

Generally speaking, applications are built around common resources, namely the databases and security realms. Here, it seems you can't make any assumptions about the client at all, so you render useless the ability to propagate the transaction and security context; the upshot being that you couldn't
use it, even if we provided support for it, which we don't.
You also want to be shielded from all the incompatibilities between the ORB vendors, that is, you want to provide a client interface to call into an ejb, that will work irrespective of the orb the client runs. From this, I gather that you can have a 1.0 or 2.1 Tao, Visibroker, IONA, etc, orb as a
client, so you can not use objects in the interface.
To accomplish this, you need to do the following:
-- design the client interface so that it is stateless
-- design the interface so that it does not include any objects or structs... actually, you can use structs, it's just more complicated.
-- use server side transactions only (this follows from the statelessness of the interface)
-- either assume that ssl will be in place by the time you need it or include a token in the interface for the authenticated user
Please, read on...
"<=one way=>" wrote:
This is the situation we have:
1) We must support both C++ and Java clients that will be requesting
services from our EJBs running in WLS. The clients are internal apps running
in different companies and we would prefer to avoid requiring our clients to
use an ORB by a specific vendor. At the same time we do not want to deal
with potential problems related to the implementation differences by
different ORB vendors. What would be the best way to handle this situation?
We support IIOP as the transport. To call into any remote interface, you must provide a java.rmi.Remote interface, and code generate the IDL from that interface using weblogic.rmic. If you follow the above strictures, and use the -noValueTypes discussed earlier, you should be able to make progress
without the promised examples.... or you can wait for the examples.
>
2) WLS documentation has the following paragraph:
"WebLogic RMI over IIOP is the framework for EJB-to-CORBA mapping support.
Currently, however, a standard for passing user identity -- required to
implement EJB-to-CORBA mapping -- does not exist and the requirement for
transaction propagation from the client is in question. While RMI over IIOP
does allow CORBA clients to access EJBeans, the following services will not
be available:
EJB transaction services
EJB security services"
Does this mean that:
2.1) CORBA client initiated transactions will not be supported,
everything else (sic) will workYes.
>
2.2) None of the EJB security services will be available in EJB method
called by a CORBA client (i.e. getCallerPrincipal() and isCallerInRole()
will fail)No. The call will not fail, they will either provide values that correspond to the default or the user configured by the weblogic.iiop.user property.
>
>
Thanks in advance