Just like JSF managed beans, CDI named beans are scoped. This means that CDI beans are contextual objects. When a named bean is needed, either because of injection or because it is referred from a JSF 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 |
| request-scoped beans are shared through the duration of a single request. A single request could refer to an HTTP request, an invocation to a method in an EJB, a web service invocation, or sending a JMS message to a message-driven bean. |
Conversation |
| The conversation scope can span multiple requests but is typically shorter than the session scope. |
Session |
| session-scoped beans are shared... |