@Retention(value=RUNTIME)
@Target(value=TYPE)
public @interface Eager

Specifies that a scoped bean is to be eagerly instantiated.

Currently supported scopes:

1. RequestScoped
2. ViewScoped
3. SessionScoped
4. ApplicationScoped

E.g. The following bean will be instantiated during application's startup:

 @Eager
 @ApplicationScoped
 public class MyEagerApplicationScopedBean {

     @PostConstruct
     public void init() {
         System.out.println("Application scoped init!");
     }
 }
 

Note: you can also use the stereotype Startup for this instead.

The following bean will be instantiated whenever a session is created:

 @Eager
 @SessionScoped
 public class MyEagerSessionScopedBean implements Serializable {

     private static final long serialVersionUID = 1L;

     @PostConstruct
     public void init() {
         System.out.println("Session scoped init!");
     }
 }
 

The following bean will be instantiated whenever the URI /components/cache (relatively to the application root) is requested, i.e. when an app is deployed to /myapp at localhost this will correspond to a URL like http://localhost:8080/myapp/components/cache:

 @Eager(requestURI = "/components/cache")
 @RequestScoped
 public class MyEagerRequestScopedBean {

     @PostConstruct
     public void init() {
         System.out.println("/components/cache requested");
     }
 }
 

Compatibility

In some (older) containers, most notably GlassFish 3, the CDI request scope is not available in a ServletRequestListener (this is actually not spec complicant, as CDI demands this scope to be active then, but it is what it is).

Additionally in some containers, most notably GlassFish 3 again, instantiating session scoped beans from a HttpSessionListener will corrupt "something" in the container. The instantiating of the beans will succeed, but if the session is later accessed an exception like the following will be thrown:

 java.lang.IllegalArgumentException: Should never reach here
  at org.apache.catalina.connector.SessionTracker.track(SessionTracker.java:168)
  at org.apache.catalina.connector.Request.doGetSession(Request.java:2939)
  at org.apache.catalina.connector.Request.getSession(Request.java:2583)
  at org.apache.catalina.connector.RequestFacade.getSession(RequestFacade.java:920)
  at javax.servlet.http.HttpServletRequestWrapper.getSession(HttpServletRequestWrapper.java:259)
  at com.sun.faces.context.ExternalContextImpl.getSession(ExternalContextImpl.java:155)
  at javax.faces.context.ExternalContextWrapper.getSession(ExternalContextWrapper.java:396)
  at javax.faces.context.ExternalContextWrapper.getSession(ExternalContextWrapper.java:396)
  

If any or both of those problems occur, a filter needs to be installed instead in web.xml as follows:

 <filter>
     <filter-name>eagerBeansFilter</filter-name>
     <filter-class>org.omnifaces.cdi.eager.EagerBeansFilter</filter-class>
 </filter>
 <filter-mapping>
 <filter-name>eagerBeansFilter</filter-name>
     <url-pattern>/*</url-pattern>
 </filter-mapping>

Note that the EagerBeansFilter will automatically disable the request listener by calling EagerBeansRequestListener.setEnabled(boolean) and disable instantiating beans from the session listener by calling EagerBeansSessionListener.setEnabled(boolean).

If so needed the listeners can also be disabled in the same way via user code.