NonStop Server Guide for BEA WebLogic Server 9.2

HP NonStop Server Guide for BEA WebLogic Server 9.2—529891-002
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6 XA Resource Manager (XARM)
The XA Resource Manager (XARM) for the HP NonStop server is a software
component specifically written for and tested with the BEA WebLogic Server. It is
written in C and Java and implements the Java XA resource interface as defined in the
Java™ Transaction API (JTA) specification. The sections listed below describe the
configuring options available:
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Configuring the WebLogic Server XA Resource Object
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Configuring the XA Resource Manager Error Output Destination
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Configuring the WLSNonStopTxHelper as a Startup Class
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Configuring JDBC Connection Pools for SQL/MX
•
Configuring the WebLogic Server Data Sources for SQL/MX
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Additional Considerations for JDBC Access to SQL/MX Databases
Normally, the WebLogic Server Transaction Manager enlists an XA resource in a
transaction only when the associated resource manager is accessed within a
WebLogic Server transaction. A special construct is needed so that a Transaction
Management Facility (TMF) transaction is associated with the thread along with the
WebLogic Server transaction. Whenever a WebLogic Server transaction associated
with a thread changes, the TMF transaction association should change.
This requirement is achieved by registering a static resource manager object with the
WebLogic Server. A static resource object is a special construct in the WebLogic
Server. A statically registered XA resource manager is enlisted in every transaction
started by the WebLogic Server. When the XARM is registered as a static resource
manager with the WebLogic Server, it interacts with the WebLogic Server to import
transaction branches into TMF when instructed by the WebLogic Server and takes part
in the commitment of the branch under the direction of the WebLogic Server
transaction manager.
As part of each WebLogic Server startup instance, the NonStop server XA resource
must be registered as a static resource with that instance. Whenever a WebLogic
Server transaction is started (either implicitly or explicitly), a branch of the transaction
is contracted to TMF by the WebLogic Server transaction manager through the
NonStop XA resource. The imported branch protects all NonStop server resources
accessed within the scope of the WebLogic Server transaction.
The static resource manager protects the NonStop server resources when it is
accessed within the scope of a WebLogic Server transaction. However, the WebLogic
Server transaction manager treats a resource as a transactional resource only if it
supports the XA resource (even if the XA resource does not really perform transaction
management).
For example, for a SQL/MX connection pool to take part in a transaction involving other
XA resources, the JDBC (Java Database Connectivity) driver for SQL/MX must have
an XADataSource driver. However, JDBC/MX does not support XADataSource and