Hi David, Thanks for the correction.
- james David E Jones-4 wrote: > > > James, > > I think that was BJ's point: the OFBiz Entity Engine is NOT an ORM tool, > ie there is no attempt to map between an object model and the relational > model in the database. We simply use the relational model itself. This > reduces redundancy (you don't have to create an object model), and it > avoid the often big/annoying problem of "impedance mismatch" between the > two very different ways of modeling and managing data. > > I never did understand why the lords of Java always felt the need to map > EVERYTHING to an object model instead of creating objects that make it > easier to work with the natural model of each thing (ie relational > databases, services, etc, etc). I guess once you get used to a certain way > of doing things it's hard to imagine doing it in any way different. > > -David > > > On Sep 18, 2010, at 2:38 AM, james_sg wrote: > >> >> Hi BJ, >> >> I treat OFBiz entity engine as an ORM that uses Map for the Object part. >> >> The gui modeler is a desktop application (not sure if it is swt based), >> that >> helps with the editing of the database definition files, and database >> schema >> migration. The gui modeler is not used in the web application, nor does >> it >> use JNLP. >> >> Cayenne also doesn't generate the html forms from the database. >> >> Anyway, I can't think of a strong business case for making entity engine >> swappable. >> I thought it is worth mentioning Cayenne since it is similar to OFBiz >> entity >> engine. >> >> - james >> >> >> BJ Freeman wrote: >>> >>> One of the reason I came to ofbiz was to get away from the bloat of ORM. >>> if I read the modeler right that is swt based Gui which introduces a >>> communication layer back to the server, unlike ofbiz being generated on >>> the fly into html, from the server. >>> >>> BTw I have a Commercial Swt Gui Generator and use it for my legacy apps >>> I converted to ofbiz, as well as the communications layer using JNL. >>> >>> ========================= >>> BJ Freeman >>> Strategic Power Office with Supplier Automation >>> <http://www.businessesnetwork.com/automation/viewforum.php?f=52> >>> Specialtymarket.com <http://www.specialtymarket.com/> >>> Systems Integrator-- Glad to Assist >>> >>> Chat Y! messenger: bjfr33man >>> >>> james_sg sent the following on 9/18/2010 12:24 AM: >>> >>> >>>> >>>> Hi all, >>>> >>>> Apache Cayenne has the closest match to OFBiz Entity Engine. >>>> >>>> A few points about Cayenne: >>>> 1. Cayenne has generic object while OFBiz has Generic Value. >>>> 2. Cayene has DerivedDbEntity (depreciating) to OFBiz's View Entity. >>>> 3. Cayenne has a gui modeler to map the database. >>>> 4. Cayenne supports applications running in cluster. >>>> 5. OFBiz requires the developer to explicitly save each generic value. >>>> In >>>> Cayenne, the developer to save the Generic Object and any associated >>>> Generic >>>> Objects are implicitly saved. >>>> 6. Like OFBiz, the database definition files for Cayenne can be >>>> separated >>>> and grouped under domains and combined at runtime. >>>> 7. Cayenne gui modeler has function to merge database changes, but >>>> OFBiz >>>> does that automatically. >>>> >>>> If there is a need or business case to support the swapping of the >>>> entity >>>> engine, it should support similar ORM and follows the api used in >>>> OFBiz. >>>> >>>> Also note there is a JPA standard for ORM that uses POJO. >>>> >>>> Regards, >>>> James >>>> >>>> >>>> Scott Gray-2 wrote: >>>>> >>>>> Hi Chris, >>>>> >>>>> Could you explain how you envisage swapping the entity engine with >>>>> hibernate considering one uses Maps (GenericValue) and the other uses >>>>> POJOs to represent data? >>>>> >>>>> Thanks >>>>> Scott >>>>> >>>>> HotWax Media >>>>> http://www.hotwaxmedia.com >>>>> >>>>> On 18/09/2010, at 1:32 AM, chris snow wrote: >>>>> >>>>>> I would see entity engine and service engine as separate modules. >>>>>> >>>>>> Each module should have clearly defined api defining how they >>>>>> interact >>>>>> with the outside world. A clearly defined api will facilitate >>>>>> swapping parts. For example, the entity engine could be replaced >>>>>> with >>>>>> a hibernate based engine as long as the api was implemented. >>>>>> >>>>>> (also there would be a module for Birt) >>>>>> >>>>>> On Fri, Sep 17, 2010 at 2:06 PM, BJ Freeman<bjf...@free-man.net> >>>>>> wrote: >>>>>>> to me framework is what has not ability to interact with the real >>>>>>> world, >>>>>>> like party, but just the tools. >>>>>>> so base layer is Entity and service engine. >>>>>>> Next layer is Webapp and Widgets. >>>>>>> next layer is Webtools >>>>>>> next layer is security and common >>>>>>> >>>>>>> A person should be able to enable those things that they want for >>>>>>> their >>>>>>> application. >>>>>>> >>>>>>> >>>>>>> >>>>>>> chris snow sent the following on 9/17/2010 4:11 AM: >>>>>>>> >>>>>>>> If you follow my instructions for 9.04 that will to a large extent >>>>>>>> give you framework independence. >>>>>>>> >>>>>>>> I think 9.04 makes a good basis for looking at modularising parts >>>>>>>> of >>>>>>>> ofbiz. For example, I would like to see the entity engine live in >>>>>>>> its >>>>>>>> own project. The entity engine from what I remember is currently >>>>>>>> tightly tied in to performing duties such as reading configuration >>>>>>>> files. Based on this, I would next focus on giving the entity >>>>>>>> engine >>>>>>>> an api for loading it's global configuration and also component >>>>>>>> configurations. That way, the entity engine could be added to >>>>>>>> ofbiz >>>>>>>> as a pure jar file and be configured by some other module (e.g. a >>>>>>>> configuration service). Isolating parts of the system like the >>>>>>>> entity >>>>>>>> engine has a lot of benefits. For example, BJ Freeman has >>>>>>>> mentioned >>>>>>>> improvements to the entity engine such as on the fly entity >>>>>>>> changes. >>>>>>>> This would be made much easier if the entity engine was not so >>>>>>>> deeply >>>>>>>> intertwined with the rest of the ofbiz code. >>>>>>>> >>>>>>>> I think github would be the ideal place for hosting this kind of >>>>>>>> effort. That way non ofbiz commiters could more easily contribute. >>>>>>>> >>>>>>>> On Fri, Sep 17, 2010 at 11:49 AM, james_sg<snowme...@hotmail.com> >>>>>>>> wrote: >>>>>>>>> >>>>>>>>> Hi Chris, >>>>>>>>> >>>>>>>>> I believe framework separation is a win-win situation and things >>>>>>>>> will >>>>>>>>> get >>>>>>>>> sorted out when the common agreement is there. >>>>>>>>> >>>>>>>>> I am using 9.04. For non-erp project, I have other favorite >>>>>>>>> framework. >>>>>>>>> >>>>>>>>> -james >>>>>>>>> >>>>>>>>> >>>>> >>>>> >>>> >>> >>> >> >> -- >> View this message in context: >> http://ofbiz.135035.n4.nabble.com/why-we-should-have-a-10-04-standalone-framework-release-tp1568563p2544837.html >> Sent from the OFBiz - User mailing list archive at Nabble.com. > > > -- View this message in context: http://ofbiz.135035.n4.nabble.com/why-we-should-have-a-10-04-standalone-framework-release-tp1568563p2545671.html Sent from the OFBiz - User mailing list archive at Nabble.com.
