XA transaction support allows a transaction to be managed by a transaction manager external to a resource adapter (and therefore external to an EIS). When an application component demarcates an EIS connection request as part of a transaction, the application server is responsible for enlisting the XA resource with the transaction manager. When the application component closes that connection, the application server cleans up the EIS connection once the transaction has completed.

Oracle recommends creating a LocalTransaction outbound connection pool for an XA transaction capable resource adapter for improved performance.

Local transaction support allows WebLogic Server to manage resources that are local to the resource adapter. Unlike XA transaction, local transaction generally cannot participate in a two-phase commit protocol (2PC). The only way a local transaction resource adapter can be involved in a 2PC transaction is if it is the only local transaction resource involved in the transaction and if the WebLogic Server Connector container uses a Last Resource Commit Optimization whereby the outcome of the transaction is governed by the resource adapter's local transaction.

A local transaction is normally started by using the API that is specific to that resource adapter, or the CCI interface if it is supported for that adapter. When a resource adapter connection that is configured to use local transaction support is created and used within the context of an XA transaction, WebLogic Server automatically starts a local transaction to be used for this connection. When the XA transaction completes and is ready to commit, prepare is first called on the XA resources that are part of the XA transaction. Next, the local transaction is committed.

If the commit fails on the local transaction, the XA transaction and all the XA resources are rolled back. If the commit succeeds, all the XA resources for the XA transaction are committed. When an application component closes the connection, WebLogic Server cleans up the connection once the transaction has completed.

If a resource adapter is configured to use no transaction support, the resource adapter can still be used in the context of a transaction. However, in this case, the connections used for that resource adapter are never enlisted in a transaction and behave as if no transaction was present. In other words, operations performed using these connections are made to the underlying EIS immediately, and if the transaction is rolled back, the changes are not undone for these connections.

For pools which support XA Transactions, WebLogic Server may try to perform transaction recovery for the Jakarta EE Connector Architecture connection pool if WebLogic Server finds pending transactions in the pool during a server startup. If pending transactions are found, WebLogic Server gets a ManagedConnection to EIS during recovery using ManagedConnectionFactory.createManagedConnection(javax.security.auth.Subject subject, ConnectionRequestInfo cxRequestInfo).

If EIS requires explicit credentials (such as user name and password) to sign-on, the you need to configure WebLogic Server with appropriate credentials by configuring a special credential mapping for the initial connection. See Initial Connection: Requires a ManagedConnection from Adapter Without Application's Request. WebLogic Server uses null as Subject if a mapping is not found.