Chapter 5. Using J2EE Connector Architecture 119
The system process and CICS interaction are shown in Figure 5-14.
Figure 5-14 System process - CICS JCA interaction
The system process routes the request with a remote call to the CICS JCA
service based on the context information and proceeds. The format handling is
performed, and then the invocation of the CICS resource adapter service is
performed. The result is returned to the system process, which then can be used
by any critical business process in the system.
5.4.5 Quality of service for J2C resource adapters
There are inherent qualities of service made available when the CICS resource
adapter is wrapped into the BPEL process. These services allow for staff
activities, transactions, and flexibility. There are other qualities of service that
comes from the J2C resource adapter and from leveraging the application server
functions. This section briefly discusses a few of these quality features.
Transactions
The application server provides transaction management to the resource
adapter. The applications server’s transaction management and the architecture
specification contracts define how transactions should be performed when a
resource adapter is running in managed mode. The transaction manager
coordinates transactions from the application component and the resource
adapter to the underlying enterprise system. It allows for easier integration with
two-phase commit transactions and multiple resource managers.
To provide transactions when interfacing with a CICS system, depending on the
environment and deployment scenario, use of the CICS ECI resource adapter
and the CTG are required. Support for global transactions is available when the
resource adapter is running on WebSphere Application Server for z/OS and
z/OS System
CTG
CICS
System Process
Partner
Link
(PL)
Context
LOCAL
REMOTE
Domain Data
Resource Adapter
Service
Data Formatting
CICS JCA
CICS RA
120 Managing Information Access to an EIS Using J2EE and Services Oriented Architecture
using a local gateway. For more information about using transactions when
integrating, with CICS see:
http://ibm.com/developerworks/websphere/techjournal/0408_wakelin/
0408_wakelin.html
Connection pooling
The connection management contract of the specification defines the roles of the
resource adapter and application server when maintaining connections to the
EIS. This connection enables the application server to provide efficient
connection pooling. It allows the application server to deal with dead and idle
connections and to reuse existing connections.
Security
The security contract allows the resource adapter to use container managed
security, which are easily defined using J2C JAAS authentication entries, similar
to the ones used earlier in “Creating and configuring the integrated test
environment” on page 115.
Security can also be achieved by leveraging the EIS systems authentication
mechanism at the connection and interaction level. Depending on the EIS and
the design of the interaction interface, there could be additional security provided
by the resource adapter.
5.4.6 For more information
For more information about the systems and technology used for this redbook,
see:
???? CICS Transaction Gateway V5 The WebSphere Connector for CICS,
SG24-6133
???? WebSphere for z/OS V5 Connectivity Handbook, SG24-7064
???? Java Connectors for CICS: Featuring the J2EE Connector Architecture,
SG24-6401
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