Hi,
I am reading the javadoc documentation and also referring to the
source code to get an understanding, but it would greatly help me if
you would answer following questions:
1. I am trying to understand the
org.apache.derby.iapi.services.context package and what it is used
for. So far my understanding is this:
a) It is a mechanism for sharing information across multiple modules
without having to pass parameters.
b) It is a mechanism for stashing away values so that a module can
get back the stashed values when it is called again.
c) It is a mechanism for associating values with a thread.
d) It is a mechanism for passing error information and cleaning up on
errors.
The javadoc comments explain how it works, but not really tell why it
is necessary.
2. Is it possible to have more than one Transaction active in a
thread? It seems to me from looking at RAMTransactionContext that
there is a notion of current transaction context. Is this a reason
why it is necessary to support the nested transaction concept?
3. Following two questions are related to the
org.apache.derby.iapi.services.monitor package.
a) Is my understanding correct that each module must know what other
module it depends upon and try to boot the required module? Thus, the
Monitor system does not inject dependencies, each module needs to
find any modules it depends upon?
b) Is a Service a synonym for a database instance on disk?
Thank you very much for your help.
Regards
Dibyendu
