src/site/xdoc/design.xml (46 lines of code) (raw):
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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>