18.6.5. Transaction Recovery Example

The following example describes how transactions are used in a situation where money is transferred from an account stored in a database to an account stored in JBoss Data Grid.

Example 18.1. Money Transfer from an Account Stored in a Database to an Account in JBoss Data Grid

  1. The TransactionManager.commit() method is invoked to to run the two phase commit protocol between the source (the database) and the destination (JBoss Data Grid) resources.
  2. The TransactionManager tells the database and JBoss Data Grid to initiate the prepare phase (the first phase of a Two Phase Commit).
During the commit phase, the database applies the changes but JBoss Data Grid fails before receiving the Transaction Manager's commit request. As a result, the system is in an inconsistent state due to an incomplete transaction. Specifically, the amount to be transferred has been subtracted from the database but is not yet visible in JBoss Data Grid because the prepared changes could not be applied.
Transaction recovery is used here to reconcile the inconsistency between the database and JBoss Data Grid entries.
Report a bug