Bill, If you use versioning on a POJO that is a the top of an object graph, will the children objects also be versions when they are modified???
I assume No. But I think it would make sense for your Versioning interceptor to wrap up children objets with the versioning proxy also when they are accessed. That way if you do a: pojo = (POJO)Versioned.makeVersioned(pojo); pojo.getAccount().getBalance().add(10.00); The modification of the Balance object will be versioned too. Does that make sense to you?? Do you do this now?? Regards, Hiram --- Bill Burke <[EMAIL PROTECTED]> wrote: > > > > -----Original Message----- > > From: > [EMAIL PROTECTED] > > > [mailto:[EMAIL PROTECTED] > Behalf Of > > Karthik > > Sent: Thursday, March 27, 2003 1:25 AM > > To: [EMAIL PROTECTED] > > Subject: RE: [JBoss-dev] AOP versioned ACID > objects 1st iteration > > > > > > Hi bill, > > The versioning of POJO is very good. I have > some issues here. If I > > version a object, then I have to maintain all the > state in the same POJO > > How is this not the general case? All application > code accesses the POJO > through the proxy. I am going to write a > constructor-pointcut that will > always return a proxy instead of the real POJO on > construction. > > > which is not the general case and will bloat the > code. The states are > > maintained in the helper classes. Also defining > each POJO as versioned is > > meaningless. If new proxies are created for each > transaction with the deep > > copy of all the state or maintain a pool and > synchronize the state after > > update, it will become real performance > bottleneck.How do you tackle this > > problem? > > There is only one proxy, but you are correct. For > each transaction, a full > snapshot is taken of the real object. All access to > the object is done > through one proxy. > > The performance hit is the full deep copy not the > synchronization. > Synchronization is only: > > realObject = snapshot; > > Remember, we're optimistically locking here. > (Although I'd like to > optionally provide a transactional lock in the near > future). > > The alternative solution is much much more complex. > The biggest problem > being, how do you determine when a POJO's state has > changed? For instance: > > Pojo.someHashMapField.get().setValue(blah). You see > my point? > > A full deep copy greatly simplifies the code. > Simplicity == robustness. > Plus I'm not even sure versioned fields would be > better performing. Field > interception is quite expensive and versioned fields > would need field > interception. > > The code is under: > varia/src/main/org/jboss/aop/plugins/Version*.java > testcase is under > testsuite/src/main/org/jboss/test/aop/bean/Version*.java > (take a look at the AOP DD under > testsuite/src/resource/aop/META-INF/jboss-aop.xml > too). > > Bill > > > > > Correct me if I am missing something. > > > > Where or when can get the code from the CVS? > > > > Thanks > > > > Karthi > > > > > -----Original Message----- > > > From: > [EMAIL PROTECTED] > > > > [mailto:[EMAIL PROTECTED] > > > Behalf Of Bill > > > Burke > > > Sent: Thursday, March 27, 2003 10:43 AM > > > To: [EMAIL PROTECTED] > > > Subject: RE: [JBoss-dev] AOP versioned ACID > objects 1st iteration > > > > > > > > > > > > > > > > -----Original Message----- > > > > From: > [EMAIL PROTECTED] > > > > > [mailto:[EMAIL PROTECTED] > > > Behalf Of Jeff > > > > Haynie > > > > Sent: Wednesday, March 26, 2003 11:51 PM > > > > To: [EMAIL PROTECTED] > > > > Subject: RE: [JBoss-dev] AOP versioned ACID > objects 1st iteration > > > > > > > > > > > > > > > > >JBoss Remoting is much more fabulous. We > need to get the > > > word out on > > > > it... > > > > > > > > I need to write some darn docs.. Too busy > trying to get a > > > new release > > > > out on our side. Not enough hours in a day. > > > > > > > > > > > > > I totally agree. And yes, a constructor > pointcut is the > > > way to go. > > > > The only downside of constructor pointcuts is > that > > > reflection bypasses > > > > the interception! > > > > > Same thing with field interception. The > problem is that unlike > > > > methods, you have to modify the bytecode of > the calling logic. > > > > > > > > Could you dynamically do an insertBefore into > the > > > CtConstructor of the > > > > advised class which would do the interception, > even on reflection? > > > > > > > > > > I'm not sure...The problem with Versioning and > Remoting is > > > that a proxy > > > object is required. You have to return a > different object > > > than the one > > > actually constructed. You getting me? I'm not > sure if this > > > can be done > > > within bytecode manipulation. I'll have to ask > the Javassist guys. > > > > > > > > I will write some testcases that put the > whole stack together with > > > > constructor pointcuts. > > > > > > > > > > I'm also working on the concept of an > abstract Container. > > > But you got > > > > me thinking that constructor pointcuts may be > enough... > > > > > > > > I was just going to email you about the > Container - just > > > looking through > > > > the code. Is this just the ability to create > an AOP namespace or > > > > something? > > > > > > > > > > I guess you could think of it in that way and > use it in that > > > way, but the > > > original intent was to handle things like > dynamic loading through the > > > persistence mechanism much in the same way an > Entity Bean > > > Container handles > > > invocations on objects that are not in memory > yet. You get > > > what I'm saying? > > > > > > Bill > > > > > > > > > > > > > > > > > > > > > > > > === message truncated === __________________________________________________ Do you Yahoo!? Yahoo! Platinum - Watch CBS' NCAA March Madness, live on your desktop! http://platinum.yahoo.com ------------------------------------------------------- This SF.net email is sponsored by: The Definitive IT and Networking Event. Be There! NetWorld+Interop Las Vegas 2003 -- Register today! http://ads.sourceforge.net/cgi-bin/redirect.pl?keyn0001en _______________________________________________ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development
