5.2.9. Components with multiple roles

Some Seam component classes can fulfill multiple roles in the system. For example, the User class is usually a session-scoped component representing the current user, but in user administration screens becomes a conversation-scoped component. The @Role annotation lets us define an additional named role for a component, with a different scope — it lets us bind the same component class to different context variables. (Any Seam component instance can be bound to multiple context variables, but this lets us do it at the class level to take advantage of automatic instantiation.)

@Name("user") 
@Entity 
@Scope(CONVERSATION) 
@Role(name="currentUser", scope=SESSION)
public class User { ... }

@Name("user") 
@Entity 
@Scope(CONVERSATION) 
@Role(name="currentUser", scope=SESSION)
public class User { ... }

The @Roles annotation lets us specify additional roles as required.

@Name("user") 
@Entity 
@Scope(CONVERSATION) 
@Roles({ @Role(name="currentUser", scope=SESSION), 
         @Role(name="tempUser", scope=EVENT)}) 
public class User { ... }

@Name("user") 
@Entity 
@Scope(CONVERSATION) 
@Roles({ @Role(name="currentUser", scope=SESSION), 
         @Role(name="tempUser", scope=EVENT)}) 
public class User { ... }