Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!news.mixmin.net!weretis.net!feeder4.news.weretis.net!storethat.news.telefonica.de!telefonica.de!newsout01.versatel.de!newsin01.versatel.de!news.osn.de!diablo2.news.osn.de!ecngs!feeder.ecngs.de!Xl.tags.giganews.com!border1.nntp.ams.giganews.com!nntp.giganews.com!local2.nntp.ams.giganews.com!nntp.bt.com!news.bt.com.POSTED!not-for-mail NNTP-Posting-Date: Sat, 29 Dec 2012 07:00:55 -0600 Date: Sat, 29 Dec 2012 13:00:53 +0000 From: lipska the kat User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:11.0) Gecko/20120410 Thunderbird/11.0.1 MIME-Version: 1.0 Newsgroups: comp.lang.java.programmer Subject: Re: Java servlet on browsers: dying or kicking ? References: <50d892e5$0$282$14726298@news.sunsite.dk> <50dbf6d1$0$80176$742ec2ed@news.sonic.net> <50dcfecc$0$292$14726298@news.sunsite.dk> <50dd5b51$0$80184$742ec2ed@news.sonic.net> <50de2260$0$293$14726298@news.sunsite.dk> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 8bit Message-ID: Lines: 48 X-Usenet-Provider: http://www.giganews.com X-AuthenticatedUsername: NoAuthUser X-Trace: sv3-jjBn/SXlOyFB9hrUd28KMqLISX4lXGvgdL24EHEUGwpIUSb5ZlD0wAlNSHDLUO8N/lzXX40Nc7jLvOD!CGcaAA+reRoe/5WfbSLdTFLQpr3PMsEuDeuBtuvEDmGLFO1yr1+FdCU0Uet3kEk/i65PxNxIyGE= X-Complaints-To: abuse@btinternet.com X-DMCA-Complaints-To: abuse@btinternet.com X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.40 X-Original-Bytes: 3556 Xref: csiph.com comp.lang.java.programmer:20800 On 29/12/12 12:22, Arved Sandstrom wrote: > On 12/28/2012 06:51 PM, Arne Vajhøj wrote: >> On 12/28/2012 12:50 PM, lipska the kat wrote: >>> What I inevitably end up with is a slightly less that perfect decoupling >>> but I like to think that eventually, given the appearance of a truly >>> scalable way to persist entire Object trees I will be able to produce a >>> business system that will be completely decoupled from earthly >>> considerations like UI and database >> >> I thought a business logic layer by definition was separate >> from UI layer and data access layer. >> >> :-) >> >> Arne >> > I do such a heavy combination of SOA and web app work that I like layers > that work for both. For my purposes Martin Fowler's Service/Application > layer picture (http://martinfowler.com/eaaCatalog/serviceLayer.html) > serves nicely as a starting point. > > In that picture business logic is mostly in the Domain/Model layer, > including business rules, and the Service/Application layer consists of > operations that cannot be assigned to any one given domain object. > > I see a good, solid Service/Application layer as being one that actually > provides services in the SOA sense. Not web services, but _services_. > These then become available for orchestration in different ways. I see the _service layer_ as aggregating fine grained business methods behind a facade. The facade then exposes what are in effect 'atomic' services that implement a particular subset of the business as seen by the outside world. As far as external clients are concerned the interface to the business is clearly defined. Martin Fowler says "[The] Service Layer defines an application's boundary" My question is how can the orchestration of service layer services outside the system boundary be controlled in a way that would be guaranteed not to potentially break the [business] rules ? [snip] lipska -- Lipska the Kat©: Troll hunter, sandbox destroyer and farscape dreamer of Aeryn Sun