I was looking to add a JavaHelper for the Tuscany implementation to help
build up SDO types from Java interfaces but ran into a couple of issues.
Can someone point me in the right direction?
The HelperProvider factory constructs the implementation in a static
initializer using:
static HelperProvider INSTANCE = getHelperProviderImpl();
static HelperProvider getHelperProviderImpl()
{
try
{
return
(HelperProvider)Class.forName("commonj.sdo.impl.HelperProviderImpl").newInstance();
} catch (Exception e)
{
throw new RuntimeException(e);
}
} // end method getHelperProvider()
This basically forces the spec and implementation classes to be
co-located in the same jar file (assuming the package is sealed) or at
least in the same classloader (if not). I know this is meant to be the
"default" implementation but wouldn't something like the JAR service
mechanism be more flexible here?
Further, all of the methods that get overridden by the implementation
have also package protection on them so the only place an implemention
can be placed is in the spec package. This includes the constructor for
HelperProviderImpl so it would seem that the only instance available is
the default one.
Is the intention here that implementations include their own version of
the spec classes in their jars? What happens if an application wants to
use two different implementations with different characteristics, or if
two applications in the same runtime use different versions? What is the
best way for an implementation to provide additional helpers?
--
TIA, Jeremy
