Gentlemen- Since this has been bugging me, I did some searching on the CGLIB mailing list and here is the result:
http://sourceforge.net/mailarchive/message.php?msg_id=9827333 I don't know any of the players over there, but from what little reading I did, the author of the above message, Chris, seems to be authoritative on the codebase. His suggestion is to test whether a class implements the net.sf.cglib.proxy.Factory interface in order to identify proxy objects. This is probably slightly better than string matching, but I'll leave it up to others to determine how much better. Thanks, Stephen On 3/5/06, Werner Guttmann <[EMAIL PROTECTED]> wrote: > Ralf, > > that just reminds me that this is not only related to Hibernate, but to > Castor JDO as well, as we are using CGLIB to create proxies for 1:1 > relations that are flagged as lazy-loaded. > > Testing for the term CGLIB in a class name does not appear to me like an > ideal solution, but I cannot think about any other way to go about this > problem. > > Regards > Werner > > Ralf Joachim wrote: > > Hi Stephen, > > > > that CGLIB stuff is a bit tricky. Maybe I can give soem informations > > that can help you to find a solution. > > > > If you create a CGLIB-Proxy for class A, the proxy will behave as being > > of a class that extends A and may also implement some additional > > interfaces. There for if 'proxy is the CGLIB-Proxy of class A you get: > > > > assertTrue(proxy instanceof A); > > assertTrue(proxy.getClass() != A.class); > > assertTrue(proxy.getClass().getName().equals("A$$ProxiedByCGLIB")); > > // (not sure on the extension of A but it includs '$$' and 'CGLIB') > > assertTrue(proxy.getClass().getSuperClass() == A.class); > > > > Depending on the construction of the proxy, the following may also be > > valid: > > > > assertTrue(proxy instanceof AnAdditionalInterface); > > assertFalse(new A() instanceof AnAdditionalInterface); > > > > The proxy itself behaves similar to java.lang.reflect.InvocationHandler. > > Each method call is passed to an invoce method where the implementer of > > the proxy can define the behaviour of the proxy. In most cases the proxy > > will add some additional functionality to the original class. At > > hibernate I expect that on every invocation of a method of A, the proxy > > will load the required object and call the same method on it. For > > internal use I also expect hibernate to implement an interface that > > offers additional methods. > > > > The problem that Paul has, and others had before, is that Castor calls > > getClass().getName() on every object it have to marshal. As this call > > does not return the name of the original calls but the one of the proxy > > (e.g. A$$ProxiedByCGLIB) Castor is not able to find the right mapping > > and uses intorspection instead. Introspection also finds the hidden > > interface methods and tries to marshal their result. > > > > The only 2 solution I can see are: > > > > 1. test for the hidden interfaces with instanceof. as this would require > > us to rever to a class of hibernate I'll refuse that. > > > > 2. test if getClass().getName() includes 'CGLIB'. if that's true call > > getClass().getSuperClass().getName() instead and use this one to search > > for a mapping. > > > > Just my 0,02 cent or maybe a bit more ;-) > > > > Regards > > Ralf > > > > > > > > Stephen Bash schrieb: > >> Paul- > >> > >> I've been pondering your problem on and off most of the day. Recently > >> someone else had a different problem also related to the CGLIB > >> proxies, so there may be some merit in looking into them. > >> > >> Just to make sure I understand the problem, the proxy classes have > >> extra get methods that return objects you don't want to marshal? And > >> since Castor validates the mapping file against the real classes, not > >> the proxy classes, marking the "field" as transient causes a > >> MappingException? > >> > >> I'll try to think about it a little and see if we can find a simple > >> solution. > >> > >> Stephen > >> > >> > >> On 3/2/06, Paul Grillo <[EMAIL PROTECTED]> wrote: > >> > >>> I have a nasty problem. Been using Castor for a couple of years for > >>> all our > >>> classes. Basically we have a large set of mapping files that > >>> generally use > >>> auto-complete="true" and we specify what is transient. > >>> > >>> We are now implementing Hibernate to perist. However, when we load > >>> up an > >>> object from the DB and then go to marshal it we see the following > >>> problem. > >>> > >>> Hibernate uses CGLIB and proxies for the class. At run time there is a > >>> "getxxxx" that returns an object that we definately do not want to > >>> marshal. > >>> > >>> So, i can'd set it transient because Castor complains that it cannot > >>> find it > >>> in the unproxied/mapped class. > >>> > >>> It will be a large problem for us to crawl through all our mapping > >>> files and > >>> specify each attribute for mapping. Is there a way around this? > >>> > >>> Are there any hooks in Castor where i can indicate to it to not > >>> marshal a > >>> particular attribute? Any code i can inject any where to handle this? > >>> > >>> thanks. > >>> > >>> oh, the decision to use Hibernate has been made. Not sure i can > >>> switch to > >>> anything else at this point. > >> > >> > > > > ------------------------------------------------- > > If you wish to unsubscribe from this list, please send an empty message > > to the following address: > > > > [EMAIL PROTECTED] > > ------------------------------------------------- > > > > > > > ------------------------------------------------- > If you wish to unsubscribe from this list, please > send an empty message to the following address: > > [EMAIL PROTECTED] > ------------------------------------------------- > >
