Thanks for you help! Should I translate your msg into Chinese and post it to a blog if you permit and your are not Chinese?
2008/3/26, Raymond Feng <[EMAIL PROTECTED]>: > > Hi, > > Let me give a try: > > 1) @target > > a) An SCA service represents a business function that a component > provides, > for example, a book store selling books. > b) An SCA reference represents a business function that a component > consumes, for example, book store needs to use shopping cart and catalog. > > The 'target' attribute of <reference> points to an SCA service that can > provide the business function required by the reference. For example, if > the > BookStore component has a catalog reference as follows: > > <component name="BookStoreComponent"> > <reference name="catalog" target="CatalogComponent/Catalog"/> > </component> > > <component name="CatalogComponent"> > ... > </component> > > The @target says CatalogComponent's Catalog service is the provider for > catalog reference. If you change it to "NewCatalogComponent/Catalog", you > basically switch to a new service provider: NewCatalogComponent's Catalog > service. > > 2) @promote > > In SCA, a pre-assembled composite can be reused as a building block for > compositions. It's achieved by <implementation.composite>. For example, > the > Catalog service itself can be developed as a SCA composite. Inside the > Catalog composite, there could be a few java components. > > <component name="CatalogComponent> > <implementation.composite composite="ns1:CatalogComposite"/> > ... > </component> > > Now the question is what services/references in the CatalogComposite will > be > made public for CatalogComponent. Service/Reference promotion is > introduced > for this purpose. > > For example, > > <composite name="CatalogComposite"> > <service name="Catalog" > promote="InternalCatalogComponent/InternalCatalog"> > ... > </service> > > <reference name="parnterCatalog" > promote="InternalCatalogComponent/partnerCatalog"> > ... > </reference> > > > <component name="InternalCatalogComponent> > ... > </component> > </composite> > > The @promote for the <service> says if CatalogComposite is used as a > component for assembly, there is a service named Catalog that makes the > InternalCatalogComponent's InternalCatalog service public. As a result, > the > CatalogComponent has a public Catalog service that can be wired to. > > The @promote for the <reference> says if CatalogComposite is used as a > component for assembly, there is a reference named partnerCatalog that > makes > the InternalCatalogComponent's partnerCatalog reference public. As a > result, > the CatalogComponent has a public partnerCatalog reference and a service > provider can be defined for this reference. > > Thanks, > Raymond > -------------------------------------------------- > From: "Fengxiang" <[EMAIL PROTECTED]> > Sent: Sunday, March 23, 2008 2:06 AM > To: <tuscany-user@ws.apache.org> > Subject: Ask for help on promot and target > > > > Dear all, > > My mother luangage is not english.So I can't got an deep understand with > > the > > specification document of assembly of sca. > > Especially on attribution of promot and target, Could you give me an > > detail > > explaination . > > Thanks. > > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > >
