Sun GlassFish Enterprise Server v3 Prelude Developer's Guide

Transaction Scope

A local transaction involves only one non-XA resource and requires that all participating application components execute within one process. Local transaction optimization is specific to the resource manager and is transparent to the Java EE application.

In the Enterprise Server, a JDBC resource is non-XA if it meets any of the following criteria:

A transaction remains local if the following conditions remain true:

Transactions that involve multiple resources are global transactions. A global transaction can involve one non-XA resource if last agent optimization is enabled. Otherwise, all resourced must be XA. The use-last-agent-optimization property is set to true by default. For details about how to set this property, see Configuring the Transaction Service.

Note –

For GlassFish v3 Prelude, transaction propagation between multiple participant processes, applications, or JVM machines is not supported.

If only one XA resource is used in a transaction, one-phase commit occurs, otherwise the transaction is coordinated with a two-phase commit protocol.

A two-phase commit protocol between the transaction manager and all the resources enlisted for a transaction ensures that either all the resource managers commit the transaction or they all abort. When the application requests the commitment of a transaction, the transaction manager issues a PREPARE_TO_COMMIT request to all the resource managers involved. Each of these resources can in turn send a reply indicating whether it is ready for commit (PREPARED) or not (NO). Only when all the resource managers are ready for a commit does the transaction manager issue a commit request (COMMIT) to all the resource managers. Otherwise, the transaction manager issues a rollback request (ABORT) and the transaction is rolled back.