Book Image

Jakarta EE Application Development - Second Edition

By : David R. Heffelfinger
Book Image

Jakarta EE Application Development - Second Edition

By: David R. Heffelfinger

Overview of this book

Jakarta EE stands as a robust standard with multiple implementations, presenting developers with a versatile toolkit for building enterprise applications. However, despite the advantages of enterprise application development, vendor lock-in remains a concern for many developers, limiting flexibility and interoperability across diverse environments. This Jakarta EE application development guide addresses the challenge of vendor lock-in by offering comprehensive coverage of the major Jakarta EE APIs and goes beyond the basics to help you develop applications deployable on any Jakarta EE compliant runtime. This book introduces you to JSON Processing and JSON Binding and shows you how the Model API and the Streaming API are used to process JSON data. You’ll then explore additional Jakarta EE APIs, such as WebSocket and Messaging, for loosely coupled, asynchronous communication and discover ways to secure applications with the Jakarta EE Security API. Finally, you'll learn about Jakarta RESTful web service development and techniques to develop cloud-ready microservices in Jakarta EE. By the end of this book, you'll have developed the skills to craft secure, scalable, and cloud-native microservices that solve modern enterprise challenges.
Table of Contents (18 chapters)
15
Chapter 15: Putting it All Together

CDI bean scopes

CDI stands for “Contexts and Dependency Injection,” CDI Beans have a scope which defines their lifecycle, their scope determines when the Jakarta EE runtime creates and destroys CDI beans. “Contexts” in “Contexts and Dependency Injection” refers to CDI scopes. When a CDI bean is needed, either because of injection or because it is referred to from a Jakarta Faces page, CDI looks for an instance of the bean in the scope it belongs to and injects it into the dependent code. If no instance is found, one is created and stored in the appropriate scope for future use. The different scopes are the context in which the bean exists.

The following table lists the different valid CDI scopes:

Scope

Annotation

Description

Request

@RequestScoped

Request-scoped...