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| |
| <document> |
| |
| <properties> |
| <title>Fulcrum YAAFI Avalon Container</title> |
| <author email="siegfried.goeschl@it20one.at">Siegfried Goeschl</author> |
| </properties> |
| |
| <body> |
| |
| <section name="Design Considerations"> |
| |
| <subsection name="Using the Avalon Context"> |
| <p> |
| There is a big specification big gap regarding the content found in |
| the Avalon Context. The pure Avalon approach is that you always |
| have the right stuff since this part of the IOC approach. Consequently |
| there is now way to check for the existence of a name/value pair. |
| On the down side each Avalon container has its own ideas about the |
| variable name to use resulting in non-reusable Avalon services. |
| </p> |
| <p> |
| YAAFI use a pragmatic approach to provide all Merlin and Fortess |
| names in the context. Therefore is should be easy to use existing |
| Fortress services within YAAFI. It is also a good idea to stick to |
| the Fortress names leaving you the option to switch Avalon containers |
| in the future. |
| </p> |
| </subsection> |
| |
| <subsection name="Decommisiong of an Avalon Service"> |
| <p> |
| YAAFI allows to decommision an Avalon service programmatically. Since |
| the services are singletons you might ending up with a stale reference. |
| Therefore it is not a good idea to decommision services you keep a |
| reference on ... :-). In the case your application design depends |
| on such a feature you should lookup the decommissioned service again |
| resulting in creating a brand new instance. |
| </p> |
| </subsection> |
| |
| <subsection name="The Reconfiguration Quest"> |
| <p> |
| Some people find it funny but YAAFI is used in 24x7 server |
| applications. Consequently our applications must be reconfigurable |
| on the fly to reduce downtime which is managed by Reconfiguration |
| Service. |
| </p> |
| </subsection> |
| |
| </section> |
| |
| </body> |
| |
| </document> |
