Java Reference
In-Depth Information
Identifying Service Candidates
Problem
You need to identify whether or not a proposed software project makes a good candidate for a
service. This process is sometimes called “service discovery” or “service elicitation.”
Solution
Start from the top down or the bottom up to zero in on a set of possible candidates, and know
that you will likely approach development from the middle out, according to business process
requirements.
Recalling that the term “service” does not imply any specific implementation platform, a pro-
posed piece of software might be a good service candidate if you can affirm at least some of
the following criteria:
1. Could this functionality be appropriately designed to satisfy the definition of a service as
stated in this chapter?
2. Is this service likely to be consumed across multiple platforms? Does it need to interoper-
ate? Would external business partners have any use for this service? Does it need to cross
functional barriers or firewalls? Can it use a popular protocol such as HTTP or SMTP?
3. Would implementing this functionality as a service help you break an integration barrier?
Would it wrap or replace a proprietary point-to-point interface? Would it operate in front
of ERP, CRM, financial applications, or other systems?
4. Does it clearly map to one or more business processes? Or is it simply a program? (It is
generally accepted that services can map to a single process, but mapping to more than
one process can offer more opportunities for reuse.)
5. Does the function that the proposed service represents cross business domains? This could
point to a greater opportunity for reuse.
6. Does the service exchange business documents or fall readily into one of the three general
service categories identified in
Identifying Different Kinds of Services
.
7. Would a business person be interested in reports on the output of this service? Would IT
be interested in monitoring its life cycle or runtime? Or perhaps it represents a functional
or utility service that in the long term could increase general business agility. (If none of
these, it may be too small an operation to merit a place in the service catalog.)
