Databases Reference
In-Depth Information
Service-enabling Existing
Systems
The heart of service-oriented architecture (SOA) is the creation of processes and
applications from existing services. The question arises, where do these services come
from? Within an SOA solution, some services will need to be written from scratch,
but most of the functions required should already exist in some form within the IT
assets of the organization. Existing applications within the enterprise already provide
many services that just require exposing to an SOA infrastructure. In this chapter, we
will examine some ways to create services from existing applications. We refer to this
process as service-enabling existing systems. After discussing some of the different
types of systems, we will look at the specific functionality provided in the Oracle SOA
Suite that makes it easy to convert file and database interfaces into services.
Types of systems
IT systems come in all sorts of shapes and forms; some have existing web service
interfaces which can be consumed directly by an SOA infrastructure, others have
completely proprietary interfaces, and others expose functionality through some
well understood but non web service-based interfaces. In terms of service-enabling
a system, it is useful to classify it by the type of interface it exposes.
Within the SOA Suite, components called adapters provide a mapping between
non-web service interfaces and the rest of the SOA Suite. These adapters allow
the SOA Suite to treat non-web service interfaces as though they have a web
service interface.
