Chapter 10. CDI

Contexts and Dependency Injection (CDI) is a specification designed to enable EJB 3.0 components "to be used as Java Server Faces (JSF) managed beans, unifying the two component models and enabling a considerable simplification to the programming model for web-based applications in Java." The preceding quote is taken from the JSR-299 specification, which can be found at http://www.jcp.org/en/jsr/detail?id=299.

JBoss EAP 6 includes Weld, which is the reference implementation of JSR-299. For more information, about type-safe dependency injection, see Section 10.1.4, “About Type-safe Dependency Injection”.

Before JSR-299 and CDI, the only way to inject dependencies in Java was to use strings. This was prone to errors. CDI introduces the ability to inject dependencies in a type-safe way.

For more information about CDI, refer to Section 10.1.2, “About Contexts and Dependency Injection (CDI)”.

The goal of Seam 2 was to unify Enterprise Java Beans (EJBs) and JavaServer Faces (JSF) managed beans.

JavaServer Faces (JSF) implements JSR-314. It is an API for building server-side user interfaces. JBoss Web Framework Kit includes RichFaces, which is an implementation of JavaServer Faces and AJAX.

Weld is the reference implementation of Contexts and Dependency Injection (CDI), which is defined in JSR-299. Weld was inspired by Seam 2 and other dependency injection frameworks. Weld is included in JBoss EAP 6.