Almost forgot a "hidden" fact :) It does not seem Jaxor supports "transparent" persistence - e.g. the beans need to be somewhat specieal and provide methods for the persistencelayer to work...net.sourceforge.jaxor.example.domain.BaseEntityInterface for which an example can be found at: http://jaxor.sourceforge.net/src/net/sourceforge/jaxor/example/domain/BaseEn tity.java
/max ----- Original Message ----- From: "Max Rydahl Andersen" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Thursday, January 23, 2003 8:29 AM Subject: Anyone up yet another philosophical comparison :) > http://jaxor.sourceforge.net/ > > A persistence layer "backed up" by the all and mighty Martin Fowler :) > > Got some nice ideas...but one point made me wonder if Hibernate could do > same/better/worse!?: > > On http://jaxor.sourceforge.net/whyJaxor.htm there is four headlines: Don't > Load More Data Than You Have To, Tell Me What Has Changed. Don't Make Me > Look!, Death to Duplication and Power of Text. > > My comments for those blocks are: > > Don't Load More Data Than You Have To > > Talks about transparent lazy loading and about the "difficulties" of > handling proxies and special code for this. > Jaxor solves this by generating the code that handles this (e.g. generating > the proxies and the code for it). > Hibernate have done this "always" and it is event better today (my opnion): > It does not need to generate the proxies upfront by the power of cglib and > the code for it is inside hibernate (no need for special case codegeneration > for this). > Note: Jaxor seems to make a point of generating code instead of having > generel reflective code....I see advantages and disadvantages in both. > > Tell Me What Has Changed. Don't Make Me Look! > Here is what it says:"Jaxor, through code generation, has the ability to > notify the session exactly when, where, and how objects are changed. In > contrast, frameworks using reflection must register the clean state of the > object when it's loaded, then upon committing the session the state of the > object is compared against it's original state to see if it has changed. If > thousands (or hundreds of thousands) of objects are loaded from the > database, committing these objects can be slower than necessary due to the > equality checks that have to be performed. Also, the state of the object is > duplicated in memory, so this may cause memory scalability problems. Jaxor > never suffers from these scalability problems. Objects are represented in > memory once. If they are updated, or deleted, then the session is notified > of the changed. No extra comparisons have to be done. " > > And here I come short - Can't find what to say in Hibernates defence here ? > (How much "double state" does Hibernate need ?) > > Death to Duplication > Well - this part is about generating code from metadata instead of manual > keeping code in sync with metadata. Here Hibernate rock :) > we got xdocbean2hbm and hbm2java and its constantly improving. > > Second part is about having a "Database synchronization tool to match > mapping information to the database schema" about handling simple "deltas" > to a schema and INFORMING about columns/tables that the metadata does NOT > cover...(maybe we should start maturing schemaupdate and build a > schemacomparison "tool" ?) > > Power of Text. > "Gui's are often wonderful marketing tools, but awful development tools" - > nuff said :) (and he continues " Even worse are gui's that don't work > directly with text files" :) > "If you are implementing a non-trivial (is there any other kind?) > application, and someone attempts to sell you an O/R mapping tool that > doesn't allow you to configure the mapping information with your favorite > text editor, run away. "... well, here Hibernate is all about text :) > > Any comments ? :) > > /max > ------------------------------------------------------- This SF.net email is sponsored by: Scholarships for Techies! Can't afford IT training? All 2003 ictp students receive scholarships. Get hands-on training in Microsoft, Cisco, Sun, Linux/UNIX, and more. www.ictp.com/training/sourceforge.asp _______________________________________________ hibernate-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/hibernate-devel
