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PersistentManager and Transaction

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PersistentManager is used to manage database connection, state of the persistent objects and transaction when the application is running. A database transaction is a unit of the application. It is used to keep integrity of your data in database. Our Persistent Library provides a transaction API for you to create, commit and rollback the transaction for your application.

Start Transaction

When you need to start a transaction, you need to get the session from the PersistentManager and call the beginTransaction function (PersistentManager.instance().getSession().beginTransaction();). Here is a sample:

PersistentTransaction t = PersistentManager.instance().getSession().beginTransaction();

Commit Transaction

After you have inserted/updated/deleted data, you can call the commit function of the transaction object to commit your changes to Database.


Rollback Transaction

In case there are any exception, you can call the rollback function to cancel all the operation.


Sample Code

The following is an example of using the transaction API.

private Course fireOK() throws PersistentException {
   PersistentTransaction t = SchoolSystemPersistentManager.instance().getSession().beginTransaction();
   try {Course lCourse = CourseFactory.createCourse();
      return lCourse;
   } catch (Exception e) {
   return null;