Java Reference
In-Depth Information
The Actors In the Model
An important part of the abstract model is played by the various actors. Because the deploy-
ment phenomenon is a complex one, the roles involved with it are not as straight-forward as
they may seem at first.
Resolving Things
In order to fully describe these roles, we have to think about what their final outcome pro-
duces. As we will see, it is useful to keep your thinking centered in the Resolution Phase.
The Producer's responsibility is to build a software product and prepare it for deployment. The
outputs of the Producer-To-Developer Publication Phase are three kinds of items, as we saw
before:
• The resources to be deployed.
•A description for each resource so that the Distributor knows exactly what to do with
them.
• The Deployment Policies, designed by the marketing staff or somebody else in the
Software Owner organization.
The first two items together are known as Annotated Resources. The easiest and standard way
to annotate a Java resource when under the form of a JAR file is to put some meta-information
in the META-INF standard directory of the JAR file itself.
We will think of resources as being annotated; that is, self-described (here, we are interested in
describing the deployment matters only). There could be a variety of different techniques to
describe resources, such as Java property files, DB entries, or XML files. The concept here is
that the annotation must work as the basis for the Deployment Policies' definition and actua-
tion.
N
OTE
It is as if the Deployment Policies were a function, and the Annotated Resources and
the Client Environment Definitions were its main input parameters.
Figure 2.7 presents the roles with their responsibilities seen from the Resolution Phase per-
spective.
