Adapters
Adapters are proxy processes that
act as an interface between the Enterprise Information System (EIS)
which include Legacy Application and communications protocols, and the
Integration Bus. Adapters used in the Java Business Integration (JBI) Model
are known as Binding Components. Binding Components have the same architecture
and connectivity requirements as other JBI Components, and differ from adapters
in that they implement Java Connector Architecture (JCA) as the standard
connectivity protocol. There are no restriction for the installation of several
An adapter is a special type of
intermediary Service that maps the signatures and message formats of one
Service to the requirements of a client. Adapters are particularly useful when
two organizations have merged or collaborated based on an MOU and Services need
to be accessed from one organization to another to serve the combined customer
base.
Generally, an Adapter is a software component that acts as a
proxy for another not equipped to communicate using the formats and protocols
of external applications.
Adapters became standard integration components in
integration from the early days of Message Oriented Middleware (MOM).
Frequently, systems that required the incorporation of an Adapter were Enterprise
Information System (EIS), including databases, ERP and CRM components and
Mainframe transaction processing systems, such as CICS.
Adapters in the SOA Stack
Adapters are bi-directional conduit of input and output.
They support dual communication protocol, a native protocol of the adapted
component, which could be APIs, IIOP, RMI, etc., and the protocol of the system
to which such components are to be integrated.
In SOA, adapters lie below the Services layer. Typically
they are connected to individual Services through the common bus, the
Middleware or the ESB, for example, ensuring complete independence of the
Adapter and its potential reuse in multiple Composite Applications.
The
widespread use of adapters led to the development of specifications that govern
their architecture and design in the Java universe. The Java EE Connector
Architecture (JCA) which is the result of JSR 112. The
specifications created a systematic approach to adapter development and
management of the adaptation mechanism of the resources.
Adapters in Java Business Integration (JBI) are
referred to as Binding Components. They are specified to use .
Performance
As shown in the diagram above, Adapters introduce a new
processing layer. This may represent an unavoidable source of inefficiency and
established an architecture and design criterion aimed at minimizing the impact
on performance. It is important to note, however, that the alternative, which
would be establishing a direct connectivity with the external application by
the Service or Services locks the Service or the Services to the current
architecture, design and available protocols of the external application. This
implies in most circumstances that a change in the revision of the external
application requires redesigning the Service or Services that interconneted
with it directly, a task greatly more onerous than upgrading a single adapter.
An Adapter is a software component introduced to facilitate
communication between two other components. Normally such components use
different mechanism to communicate with other components, and at times no such
a feature at all. The Adapter is designed to comply with the requirements of
each component for communication, or use available access to methods and
functions in each component when necessary to act as mediator between them. As
such, the adapter appears to a component as a proxy for the other component.
Adapters are normally bi-directional carrying messages to
and from each attached component.
Adapters rely on whatever communication protocol is
served by each of the components it connects to. These could be provided by the
component designers or are offered in the form of APIs.
Adapters became standard components in integration when
integrating one or more of the Enterprise Information System (see EIS), such as
the human resource system or the financial system or their components.
In SOA (see SOA) adapters lie below the Services layer and
connected them to the EIS through the common bus, the ESB (see ESB), as
detailed Figure A-I, below.
Note that the processing layer that adapters introduce is,
at time, a source of inescapable inefficiency suggesting specific styles in
their architecture, design and coding to minimize their impact on performance.
Standard Adapters
Most vendors of integration products provide a set of
adapters to integrate common IES products, such as RDBMS, Human Resources and
others. Specialist vendors provide adapters for common integration products.
Adapter SDKs
Some integration products provide an SDK for developing
custom adapters…
Adapters in Java Business Integration (see JBI)
Adapters are, at times, referred to as Binding Components
(see Binding Components). They are specified to use Java EE Connector
Architecture (see JCA).
-K – 2009-06-05.
