Book Image

Apache Geronimo 2.1: Quick Reference

Book Image

Apache Geronimo 2.1: Quick Reference

Overview of this book

Apache Geronimo is a robust, scalable, secure, and high-performing application server. But like all application servers, this power comes with a steep learning curve. This book can help you save your time and get working with Geronimo in matter of a few hours. This book is a quick-reference guide to Apache Geronimo that mitigates the starting pains that most developers have when they migrate to a new Application Server. It will help you to extend and amplify your existing development skills, empowering you to build new types of applications regardless of the platform or browser. The book will introduce you to the exciting features of Apache Geronimo Application Server. You will see how easily you can develop and deploy Java EE 5 applications on Geronimo. It covers everything from downloading the server to customizing it using custom GBeans. By following the practical examples in this book, you will be able to develop applications quickly using Geronimo Eclipse Plugin. The book covers Geronimo internals in detail, which helps you write custom services on Geronimo. Also, it helps you to gain a deep understanding of Geronimo plugin architecture and teaches you to extend your server functionality via plugins. By the end of the book, you will develop proficiency in Geronimo and Java EE 5 application development.
Table of Contents (21 chapters)
Apache Geronimo 2.1
Credits
About the Authors
About the Reviewer
Preface

Transactions


A transaction is often defined as an indivisible unit of work. Transactions are used to maintain the integrity of data in business applications. A transaction can end either in a commit or in a rollback. A transaction that ends in commit will result in saving the data modifications done by its component statements. A transaction ends in rollback if any of its component statements fail. Data modifications are not saved in this case. In case of an EJB, how the beginning and ending of transactions—referred to as transaction boundaries —are set is determined by specifying whether the EJB uses container-managed or bean-managed transactions. The type of transactions used by the EJB is specified by using the transaction-type element in the EJB deployment descriptor, or by using annotations, as discussed later in this section. The following XML fragment is an example of a session bean using container-managed transactions.

<enterprise-beans>
<session>
<ejb-name>HelloworldBean...