Is that a relatively new feature because we're still on 1.4m2 (2008/05/24) and haven't had any trouble with non serializeable model objects when going back to pages that have been spooled to disk.
Maybe if it's a newer feature and we upgrade to the latest wicket we might start seeing some problems due to the lack of serializability of our model objects.... hmmm Chris > to keep memory overhread low only the last visisted page is stored in > http session. the rest of the pages are spooled to disk for long-term > storage in case the user uses the back button, and are cleaned up on > session expiration. > > -igor > > On Thu, May 28, 2009 at 6:54 PM, Chris Colman > <chr...@stepaheadsoftware.com> wrote: > > When you say "offline storage" do you mean that the user has chosen to > > save pages for future offline reference or do you mean a more > > 'automated' process that wicket performs when system memory becomes too > > low? > > > > Chris > > > >> -----Original Message----- > >> From: Igor Vaynberg [mailto:igor.vaynb...@gmail.com] > >> Sent: Friday, 29 May 2009 11:43 AM > >> To: users@wicket.apache.org > >> Subject: Re: Anemic domain model and are @SpringBean's compatible with > > the > >> solution in "Spring 2.0 vs. the Anemic Domain Model"? > >> > >> well, this is why salve removes the dependency field to at least help > >> with those. > >> > >> other then that you can use a loadabledetachablemodel to release the > >> reference when the page is not used. > >> > >> -igor > >> > >> On Thu, May 28, 2009 at 6:40 PM, Chris Colman > >> <chr...@stepaheadsoftware.com> wrote: > >> > Is that controllable? > >> > > >> > What if I have complex object models referenced from wicket UI > >> > components that I don't want (can't reasonably with Java's non > > optimal > >> > serialization) serialized? > >> > > >> > If we're serializing for offline storage aren't we going to require > > the > >> > underlying model objects to get serialized as well? > >> > > >> >> -----Original Message----- > >> >> serialization in the context when you need to serialize the object > > - > >> >> eg wicket serializes its pages for offline storage, etc. > >> >> > >> >> -igor > >> >> > >> >> On Thu, May 28, 2009 at 5:51 PM, Chris Colman > >> >> <chr...@stepaheadsoftware.com> wrote: > >> >> > Another extremely light weight IoC with ORM wrapping (JDO and > >> > Hibernate) > >> >> > is exPOJO at http://www.expojo.com > >> >> > > >> >> > No need for old fashioned DAOs etc., just POJOs being persisted > >> >> > transparently the way they should be. > >> >> > > >> >> > In terms of serialization: > >> >> > > >> >> > Is that for the purpose of scaling in a cluster environment? I > > vote > >> > for > >> >> > 'session affinity' every time - it's almost necessary when you > > have > >> >> > anything more sophisticated than an anemic domain model. Do you > >> > really > >> >> > want to be shifting complex object models from server to server > > via > >> >> > serialization? > >> >> > > >> >> > If it's not for a cluster environment but for a single server to > >> > allow > >> >> > stale sessions to be swapped out then let the garbage collection > >> > clean > >> >> > out the ORM's object cache instead. > >> >> > > >> >> >> -----Original Message----- > >> >> >> From: Igor Vaynberg [mailto:igor.vaynb...@gmail.com] > >> >> >> Sent: Friday, 29 May 2009 3:38 AM > >> >> >> To: users@wicket.apache.org > >> >> >> Subject: Re: Anemic domain model and are @SpringBean's > > compatible > >> > with > >> >> > the > >> >> >> solution in "Spring 2.0 vs. the Anemic Domain Model"? > >> >> >> > >> >> >> On Thu, May 28, 2009 at 10:09 AM, Kent Larsson > >> >> > <kent.lars...@gmail.com> > >> >> >> wrote: > >> >> >> > Nice! I think Salve looks great! And it solves more than this > >> >> > problem, > >> >> >> > I like the design by contract module too as it allows me to > >> > validate > >> >> >> > parameters in a bit more declarative way. > >> >> >> > > >> >> >> > Do you think Salve is ready to be used in production? I'm a > > bit > >> >> >> > concerned by "Although already usable, Salve is still in its > >> >> > infancy. > >> >> >> > Not all features have been implemented and not all problems > >> > worked > >> >> >> > out.". I only see one open issue and it doesn't seem too major > >> > for > >> >> > me > >> >> >> > to pick it up. > >> >> >> > >> >> >> we have been using it in production for a while without any > >> > problems. > >> >> >> i just need to find the time to update the website text :) > >> >> >> > >> >> >> > If I'm not mistaken Salve may be used (for lots of things, but > >> > one > >> >> > is) > >> >> >> > to solve serialization issues with Spring beans in Wicket > >> >> > components? > >> >> >> > But isn't that the same issue that the Wicket IOC and it's > >> >> > @SpringBean > >> >> >> > annotation solves? > >> >> >> > >> >> >> wicket ioc can only take it so far. because it has to generate a > >> > proxy > >> >> >> there are limitations to what classes can be proxies - eg no > > final > >> >> >> methods, default constructor, etc. salve doesnt use a proxy so > > it > >> >> >> doesnt have any problems. > >> >> >> > >> >> >> although small, wicket ioc does have an overhead of having to > >> >> >> serialize the proxy with the componnet. since salve removes the > >> > field > >> >> >> it has no such overhead, this is more important when you are > >> > returning > >> >> >> large resultsets of entities that use dependencies. > >> >> >> > >> >> >> > If that's the case: Could I use Spring to inject my entities > > with > >> >> >> > DAO's for now, and use the @SpringBean annotation on those as > >> > well > >> >> > in > >> >> >> > my Wicket components (In those cases I have entities as class > >> > vars)? > >> >> >> > And the @SpringBean will solve the serialization issue? > >> >> >> > >> >> >> you can use whatever works for you. salve is an alternative :) > >> >> >> > >> >> >> > By just looking at Salve a bit it seems I could migrate to > > Salve > >> > in > >> >> >> > two steps that way. And it might be a pretty smooth path to > > take? > >> > It > >> >> >> > would mean that I inject 1000 entities for no good reason. But > > if > >> > I > >> >> >> > see a performance problem in doing so I could just migrate to > >> > Salve? > >> >> >> > By smooth path I mean that I would have access to my DAO's in > > my > >> >> >> > entities and would essentially only change the dependency > >> >> > annotations > >> >> >> > and setup Salve. > >> >> >> > >> >> >> as long as you do not use spring-specific injection rules you > >> > should > >> >> >> be fine. salve uses lookup by type primarily, but also does have > >> >> >> @SpringBeanId that can be used as a qualifier. > >> >> >> > >> >> >> > >> >> >> > Of course, if Salve is production ready. Then could I throw > > out > >> >> > Wicket > >> >> >> > IOC and the @SpringBean annotation and use Salve instead to > > solve > >> >> >> > serialization issues? In this case I would use Salve for my > >> >> >> > presentation/Wicket -layer as well as dependency injection in > > my > >> >> >> > entities and Spring as I already do for my service/business > >> > -layer > >> >> > and > >> >> >> > my persistence/DTO -layer. Or would it be nicer to have Salve > >> > handle > >> >> >> > dependencies in the last two layers as well? > >> >> >> > >> >> >> we use salve to inject across all layers. it gives you a > > consistent > >> >> >> approach to use and mock in unit tests. we have a spring context > >> > that > >> >> >> contains true services - eg session factory, mail sender, credit > >> > card > >> >> >> processor, etc. all of our domain model then uses salve to > > inject > >> >> >> these wherever needed. > >> >> >> > >> >> >> -igor > >> >> >> > >> >> >> > A lot of questions and text. Thanks for reading this far! :-) > >> >> >> > > >> >> >> > Best regards, Kent > >> >> >> > > >> >> >> > > >> >> >> > > >> >> >> > On Thu, May 28, 2009 at 5:36 PM, Igor Vaynberg > >> >> > <igor.vaynb...@gmail.com> > >> >> >> wrote: > >> >> >> >> this is why i built salve.googlecode.com > >> >> >> >> > >> >> >> >> you can easily hook it into spring and have all your objects > >> > (doman > >> >> >> >> objects or wicket components) injected via @Dependency > > without > >> >> >> >> worrying about serialization issues or eager injection - eg > > if > >> > you > >> >> >> >> load a result set of 1000 hibernate entities that need > > injection > >> >> > you > >> >> >> >> dont want all those injected for no reason. > >> >> >> >> > >> >> >> >> -igor > >> >> >> >> > >> >> >> >> On Thu, May 28, 2009 at 6:38 AM, Kent Larsson > >> >> > <kent.lars...@gmail.com> > >> >> >> wrote: > >> >> >> >>> Hi, > >> >> >> >>> > >> >> >> >>> Our current architecture: > >> >> >> >>> --- > >> >> >> >>> > >> >> >> >>> We're currently using a 3-tier architecture (presentation, > >> >> >> >>> service/business and persistence) consisting of Wicket (+ a > >> > little > >> >> >> >>> Spring), Spring and Spring + Hibernate: > >> >> >> >>> > >> >> >> >>> Wicket: > >> >> >> >>> > >> >> >> >>> Does presentation, we're not inside a transaction / > > Hibernate > >> >> > session > >> >> >> >>> so all used fields must be loaded by Spring. We call Spring > >> >> > singleton > >> >> >> >>> beans and annotate those fields with @SpringBean. > >> >> >> >>> > >> >> >> >>> Spring: > >> >> >> >>> > >> >> >> >>> In the service layer we have Spring singleton beans, > > services, > >> >> > which > >> >> >> >>> are called from the Wicket layer. We have our transaction / > >> >> > Hibernate > >> >> >> >>> session boundary at this layer. We call DAO's from this > > layer. > >> >> >> >>> > >> >> >> >>> Spring + Hibernate: > >> >> >> >>> > >> >> >> >>> Our DAO's are Spring singleton beans which performs database > >> >> >> >>> operations using HibernateTemplate. > >> >> >> >>> > >> >> >> >>> And common to all the layers are our entities. We use the > >> > @Entity > >> >> >> >>> annotation on them (not XML), from the Wicket layer we just > > use > >> >> > the > >> >> >> >>> accessor methods making sure that the relevant fields are > >> > loaded > >> >> > (as > >> >> >> >>> we would get an exception if they were Lazy and not yet > >> > loaded). > >> >> > Our > >> >> >> >>> entities are stupid, they lack logic and are used mostly > > like a > >> >> > struct > >> >> >> >>> in C/C++. > >> >> >> >>> > >> >> >> >>> I think the general pattern is pretty common for Java EE and > >> >> > Spring > >> >> >> >>> based web applications (feel free to disagree!). Yet it's > >> >> > classified > >> >> >> >>> as an anti-pattern by Martin Fowler as we are using mostly > >> >> > procedural > >> >> >> >>> programming and have an anemic domain model ( > >> >> >> >>> http://en.wikipedia.org/wiki/Anemic_Domain_Model ). > >> >> >> >>> > >> >> >> >>> What I would like: > >> >> >> >>> --- > >> >> >> >>> > >> >> >> >>> I would like to use a more OOP approach and have logic in > > our > >> >> > current > >> >> >> >>> entities, creating a rich domain model. For that to work in > > all > >> >> > cases > >> >> >> >>> they need to be able to load and save data. I would still > > use a > >> >> > Spring > >> >> >> >>> singleton bean's for different services. But instead of > >> > changing > >> >> > the > >> >> >> >>> entities like structs they would be rich objects capable of > >> >> > chaning > >> >> >> >>> themself's and other objects. > >> >> >> >>> > >> >> >> >>> I found this article very interesting: > >> >> >> >>> > > http://www.nofluffjuststuff.com/blog_detail.jsp?rssItemId=96860 > >> >> >> >>> > >> >> >> >>> But how would something like that work with Wicket? Could I > >> > just > >> >> > use > >> >> >> >>> @SpringBean like I'm currently doing but use it on both > >> > "entities" > >> >> > and > >> >> >> >>> Spring singleton services? > >> >> >> >>> > >> >> >> >>> For me this has a purely practical benefit, as I could use > > some > >> >> >> >>> inheritance in the domain object model to create different > >> >> > variations > >> >> >> >>> of logic and not just data. Wicket feels quite agile and > > nice > >> > to > >> >> > work > >> >> >> >>> with, but I still feel that the current architecture is a > > bit > >> >> > stale > >> >> >> >>> and seldom supports elegant OO solutions (that said, of > > course > >> >> > things > >> >> >> >>> can still be solved elegantly, I just think it would be > > easier > >> > if > >> >> > I > >> >> >> >>> could do it in a more OO oriented way). > >> >> >> >>> > >> >> >> >>> Comments? What are the pros and cons of this kind of > >> > architecture? > >> >> >> >>> > >> >> >> >>> All comments are greatly appreciated! > >> >> >> >>> > >> >> >> >>> Best regards, Kent > >> >> >> >>> > >> >> >> >>> > >> >> > > >> > > > --------------------------------------------------------------------- > >> >> >> >>> To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org > >> >> >> >>> For additional commands, e-mail: > > users-h...@wicket.apache.org > >> >> >> >>> > >> >> >> >>> > >> >> >> >> > >> >> >> >> > >> >> > > >> > > > --------------------------------------------------------------------- > >> >> >> >> To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org > >> >> >> >> For additional commands, e-mail: users-h...@wicket.apache.org > >> >> >> >> > >> >> >> >> > >> >> >> > > >> >> >> > > >> >> > > >> > > > --------------------------------------------------------------------- > >> >> >> > To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org > >> >> >> > For additional commands, e-mail: users-h...@wicket.apache.org > >> >> >> > > >> >> >> > > >> >> >> > >> >> >> > >> > > > --------------------------------------------------------------------- > >> >> >> To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org > >> >> >> For additional commands, e-mail: users-h...@wicket.apache.org > >> >> >> > >> >> >> > >> >> >> No virus found in this incoming message. > >> >> >> Checked by AVG - www.avg.com > >> >> >> Version: 8.5.339 / Virus Database: 270.12.44/2140 - Release > > Date: > >> >> > 05/28/09 > >> >> >> 18:09:00 > >> >> > > >> >> > > >> > > > --------------------------------------------------------------------- > >> >> > To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org > >> >> > For additional commands, e-mail: users-h...@wicket.apache.org > >> >> > > >> >> > > >> >> > >> >> > > --------------------------------------------------------------------- > >> >> To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org > >> >> For additional commands, e-mail: users-h...@wicket.apache.org > >> >> > >> >> > >> >> No virus found in this incoming message. > >> >> Checked by AVG - www.avg.com > >> >> Version: 8.5.339 / Virus Database: 270.12.44/2140 - Release Date: > >> > 05/28/09 > >> >> 18:09:00 > >> > > >> > > > --------------------------------------------------------------------- > >> > To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org > >> > For additional commands, e-mail: users-h...@wicket.apache.org > >> > > >> > > >> > >> --------------------------------------------------------------------- > >> To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org > >> For additional commands, e-mail: users-h...@wicket.apache.org > >> > >> > >> No virus found in this incoming message. > >> Checked by AVG - www.avg.com > >> Version: 8.5.339 / Virus Database: 270.12.44/2140 - Release Date: > > 05/28/09 > >> 18:09:00 > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org > > For additional commands, e-mail: users-h...@wicket.apache.org > > > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org > For additional commands, e-mail: users-h...@wicket.apache.org > > > No virus found in this incoming message. > Checked by AVG - www.avg.com > Version: 8.5.339 / Virus Database: 270.12.44/2140 - Release Date: 05/28/09 > 18:09:00 --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org For additional commands, e-mail: users-h...@wicket.apache.org