Book Image

JBoss Weld CDI for Java Platform

By : Kenneth Finnigan
Book Image

JBoss Weld CDI for Java Platform

By: Kenneth Finnigan

Overview of this book

CDI simplifies dependency injection for modern application developers by taking advantage of Java annotations and moving away from complex XML, while at the same time providing an extensible and powerful programming model. "JBoss Weld CDI for Java Platform" is a practical guide to CDI's dependency injection concepts using clear and easy-to-follow examples. This will help you take advantage of the power behind CDI, as well as providing a firm understanding of how to use it within your applications. "JBoss Weld CDI for Java Platform" covers all the major aspects of CDI, breaking it down into understandable pieces. This book will take you through many examples of how these concepts can be utilized, helping you get up and running quickly and painlessly. "JBoss Weld CDI for Java Platform" gives you an insight into the different scopes provided by CDI and the use cases for which each has been designed. You will learn everything about dependency injection, scopes, events, producers, and more from JBoss Weld CDI, as well as how producers can create new beans for consumption within your application. You will also learn how to build a real world application with CDI using JSF and AngularJS for different web interfaces.
Table of Contents (17 chapters)
JBoss Weld CDI for Java Platform
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

The conversation scope


The concept of a conversation will be familiar to those of us that have developed applications with Seam 2. In CDI, the conversation scope is very similar to the session scope, with the main difference being that its activation and deactivation is controlled by our application and not the container.

The conversation scope is also associated with a particular browser tab of a user, unlike the session, which is typically shared between tabs by browsers.

Each conversation is a way to represent a single unit of work that a user will perform to achieve a specific goal or task. As the conversation context holds the state associated with a unit of work by the user, there will be multiple conversations for a single user if they are working on multiple tasks at the same time.

The conversation context lifecycle

The conversation context is the context object for the @ConversationScoped built-in scope annotation.

The conversation context is active during any JSF faces or non-faces...