Java Reference
In-Depth Information
Java EE Connector Architecture (JCA)
TheJavaEEConnectorArchitecture1.7SpecificationwasdevelopedunderJSR322.
This section just gives you an overview of improvements in the API. The complete
document specification (for more information) can be downloaded from
http://jcp.org/
What is JCA?
Generally,
Enterprise Information Systems
(
EIS
s) of large companies are com-
posed of a number of tools such as
Enterprise Resource Planning
applications
(
ERP
, that is
SAP
),
Customer Relationship Management
applications (
CRM
, that
is
salesforce.com
)
, mainframe Transaction Processing applications, legacy applica-
tions and Database Systems (such as Oracle). In such an environment, the develop-
ment of a new solution may require access to one or more of these tools to retrieve
information or perform processing: we then talk of an
Enterprise Application Integ-
ration
(
EAI
). In the absence of a standard solution, this integration will be costly to
both vendors and developers. Vendors will develop APIs to manage communication
between different kinds of servers and developers will address EISs case by case and
will implement the technical features (connection polling, transaction security mech-
anism, and so on) required by the application. Hence the need for JCA.
The Java EE Connector Architecture (JCA) is a specification that aims to standardize
access to heterogeneous existing EISs from Java EE platforms. To this end, it defines
a set of contracts that enable developers to access the different EISs seamlessly from
a common interface called the
Common Client Interface
(
CCI
). For those who have
already been working with
JDBC
, understanding of the functioning of JCA is a little
easier. A JCA connector consists of two main elements:
•
Common Client Interface
(
CCI
): This API is to EISs as JDBC is to data-
bases. In other words, the CCI defines a standard client API that allows com-
ponents to access EISs and perform processing.
•
Resource Adapter
: This is a specific implementation of the CCI for a given
EIS. It is provided by the vendor, which guarantees the execution of the fea-
tures of its EIS through the JCA. The Resource Adapter, is packaged in a
.rar
archive called
Resource Adapter Module
, and it must obey some
contracts (system level contracts) in order to be integrated into a Java EE plat-
