Use this task when you call an Enterprise
JavaBeans® (EJB) application that is deployed on WebSphere® Application Server for z/OS® from an external address space within a
client-initiated transaction. The Customer Information Control System
(CICS®) environment is the only environment where
transactional support is supported.
Before you begin
The client process must be running on a z/OS operating system,
and the client environment must support transactional semantics. The
connection between the client and the WebSphere Application Server
server is configured to support transactions. Also, the client must
have called the Register API with the TRANSACTIONAL flag set to the
value of 1.
About this task
This process starts when you begin a transaction in a client
environment. The client calls an EJB application that is running on
WebSphere Application Server for z/OS and propagates the new transaction
to the application server. The semantics for starting a transaction
in the client environment varies based on the client environment.
Refer to the CICS documentation for information about the semantics
for starting a transaction in a CICS client environment.
Procedure
- Deploy an EJB application on
WebSphere Application Server. Use a transaction attribute, such as
required, support or mandatory, on the execute method.
- Start a transaction on the client application using the
transactional semantics. The client application performs transactional
work that is required in the client environment.
- Use the Invoke (BBOA1INV) API or the Send Request (BBOA1SRQ)
API to make a remote call with the client program to the EJB application
that is deployed on WebSphere Application Server. The transaction
context propagates to the WebSphere Application Server server and
the EJB application runs under the transaction context.
- Use the transactional semantics of the client environment
to commit or end the transaction independent of the outcome of the
WebSphere Application Server server transaction.
Results
The new transaction is propagated to the WebSphere Application Server for z/OS server. The client commits the transaction and a single
two-phase commit completes the transaction across the two address
spaces.