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JBoss Seam 2.x提供了预置的几种Scope，如@Scope(ScopeType.SESSION)等，但不能扩展。
JavaEE 7 CDI也提供了预置的几种Scope，如@SessionScoped。此外，还可以扩展实现新的Scope。
两者内置的Scope的对比：
| Seam 2 Scope | CDI Scope |
| Event | @RequestScoped |
| Session | @SessionScoped |
| Stateless | No exact match. The stateless scope is used primarily for Stateless Session Beans (EJB) in Seam 2. A Stateless session bean can be bound to the @Dependent context in a CDI application. |
| No exact match | @Dependent Means creating a new instance for each injection point. |
| Page | No exact match. |
| Conversation | No exact match. There are several alternatives which help to maintain conversational state: CDI @ConversationScoped — keeps conversational state between many requests, needs to be programmatically started and stopped. JSF Flash scope — keeps state between two requests and possibly different views. DeltaSpike Grouped Conversation scope — keeps state per-window, is started automatically when a grouped-conversation-scoped bean is accessed, maintains separate conversations for each bean or groups of beans. |
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