Enterprise JavaBeans™ Component Architecture: Designing and Coding Enterprise Applications

6.4. Transaction Overview

Business transactions are frequently carried out in a series of separate steps. Consider the following example where a customer purchases an airline ticket online. Here we use pseudocode that shows the required steps in a transactional environment.

try {
  startTransaction();
    reserveFlight();
    payForFlight();
  commitTransaction();
} catch (Exception ex) {
    rollbackTransaction();
}

For this transaction to complete, all steps must be successful. Otherwise, data may be inconsistent. These separate steps make up a transaction context, which is viewed as a single operation.

A transaction that commits means that all steps in the transaction were successful and data is saved. A transaction that rolls back means that one or more ...