Subsystem responsibilities: WSDD

[Glyn Normington <gl...@uk.ibm.com>]

Glen Daniels and I are working to improve the modularity of Axis's
"configuration" subsystem and are collecting together the WSDD-related
responsibilities and removing them from the non-config. parts of Axis such
as AxisEngine. We discussed this on the 'phone yesterday and put some
sandbox code in a 'config-work' cvs branch which we aim to improve and
merge into the main trunk in the next few days. Here are some points we
discussed:

1. The configuration, e.g. as defined in WSDD, defines factory classes,
options, and scopes for various handler types.

2. The configuration from an engine's perspective consists of a handler
'registry' (i.e. a collection of factories) and some 'global' options. We
should introduce an EngineConfiguration interface to provide access to this
configuration information by an engine.

3. Three is a fairly close relationship between configuration providers and
the registry. Both are really part of the "configuration" subsystem. The
engine should ideally not be aware of the distinction between configuration
providers and registries so long as it has access to the
EngineConfiguration that it needs.

4. The engine should not be directly involved in the details of how the
configuration is constructed or modified as that tends to pull in types
which are specific to particular configuration mechanisms such as WSDD.

5. An engine's configuration should be modified by getting hold of its
EngineConfiguration, modifying that, and then notifying the engine so it
can refresh its global options (and potentially other information).

Glyn