[jboss-as7-dev] PART 3! of EJB Remote client design

[David M. Lloyd]

On 09/22/2011 03:52 AM, Carlo de Wolf wrote:
> On 09/22/2011 07:00 AM, David M. Lloyd wrote:
>> Client JNDI Revisited!
>> ----------------------
>>
>> Based on feedback here and in IRC, we're changing our approach to client
>> EJB thus:
>>
>> A new JNDI "scheme" will be introduced called "ejb". Lookups into this
>> scheme following a naming convention will yield remote EJB proxies
>> directly. If the interface is not stateful, then the proxy is
>> immediately available without a server round-trip.
>>
>> The format for "ejb" scheme names is like this (square brackets are not
>> literal; they indicate that the enclosed section is optional):
>>
>> "ejb:appname/modulename/[distinctname/]beanname!interface[?stateful]"
>>
>> The "appname", "modulename", and "distinctname" are the identifying
>> names of the EJB deployment. "beanname" is the EJB-spec name of the
>> EJB. "interface" is the Java type name of the interface being returned.
>> The "?stateful" query parameter indicates that a session should be
>> initiated on lookup.
>>
>> Since it is likely that users will erroneously use "?stateful" on a
>> stateful home interface (which is itself stateless), the lookup code
>> will detect whether the interface extends EJBHome before attempting to
>> initiate session, and if found will instead emit a warning.
>
> Both a SLSB and a SFSB can have an EJBHome interface for their remote
> home view. So I don't see how this can play a role in determining the
> session characteristic.
>
> In fact a call to a home view is always session-less, both for SLSB and
> SFSB. The proxy returned by the create method represents the possible
> session.

That's what I said.  EJBHome are always stateless.  Therefore if 
?stateful is given for an EJBHome, it is ignored and a warning is issued.

>> This gives us configuration-free JNDI. Also, it gives us a JNDI name
>> scheme we can use in server-side EJB references as a lookup-name which
>> can create dependency-free injections of remote EJBs that may not be
>> present on the current system. And it's also nice in that it doesn't
>> interfere with "java:" spec lookups at all.
>>
>> This should address all the issues raised with client JNDI thus far.
>>
>
> Binding the URL ObjectFactory to java:something would result in exactly
> the same functionality. We can still offer this choice to users.

Except that "java:" belongs to EE, and this is very much non-spec.  I 
don't think this type of functionality belongs in "java:" under any 
circumstances.

-- 
- DML