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    <p>CDI has no view scope, because it <a href="https://stackoverflow.com/questions/7812985/cdi-missing-viewscoped-and-flashscoped">doesn't have the notion of a view</a>, so if you need that scope, CDI in its pure form can't do it. View scope basically means <a href="https://stackoverflow.com/questions/5220407/viewscoped-works-like-requestscoped-why/5220668#5220668">request scope + being AJAX-ready</a>. It's <strong>not</strong> a JSF view, like a page named <code>xyz.xhtml</code>, even though you see JSF <code>&lt;f:viewParam&gt;</code> and the likes. A frequent use case with view-scoped beans is <a href="http://balusc.blogspot.com/2011/09/communication-in-jsf-20.html#ProcessingGETRequestParameters" rel="nofollow noreferrer">how to get GET parameters into a such a bean</a>. Also <a href="https://stackoverflow.com/questions/4888942/viewparam-vs-managedpropertyvalue-param-id">read this</a>.</p> <p>Note that CDI rather lives at the EJB/service layer than the JSF/presentation layer. <a href="http://www.hascode.com/2011/02/creating-a-sample-java-ee-6-blog-application-with-jpa-ejb-cdi-jsf-and-primefaces-on-glassfish/" rel="nofollow noreferrer">This blog</a> has a nice overview.</p> <p>As such <code>@ManagedBean</code> cannot be fully replaced by CDI, again if you're using <code>@ViewScoped</code> beans - at least not without <a href="http://www.verborgh.be/articles/2010/01/06/porting-the-viewscoped-jsf-annotation-to-cdi/" rel="nofollow noreferrer">extending CDI</a> or using the <a href="http://docs.jboss.org/seam/3/faces/latest/reference/en-US/html/scopes.html#viewscoped" rel="nofollow noreferrer">Seam 3 Faces module</a>. Using view-scoped beans is almost always going to happen when using AJAXed JSF 2-based GUI toolkits like RichFaces, PrimeFaces, IceFaces etc.</p> <p>Mixing annotations from the wrong Java EE 6 packages <em>can</em> get you in trouble unexpectedly, again when using RichFaces or a similar API:</p> <pre><code>@javax.faces.bean.ManagedBean @javax.faces.bean.[Jsf]Scoped </code></pre> <p>are for components used <strong>solely</strong> at the presentation layer, here by RichFaces, PrimeFaces, etc. Some rich components <a href="http://community.jboss.org/thread/173633" rel="nofollow noreferrer">seem to have problems with CDI-annotated and JSF-annotated helper beans</a>. If you get strange behavior from your beans (or beans that seem to do nothing) the wrong mix of annotations might be the cause.</p> <p>Mixing JSF and CDI, like</p> <pre><code>@javax.inject.Named @javax.faces.bean.[Jsf]Scoped </code></pre> <p>is possible and works in most cases when referenced from JSF pages, however there are some little-known issues/drawbacks, e.g. when <a href="https://stackoverflow.com/questions/7723417/getting-a-get-request-param-into-an-viewscoped-bean">using a JSF scope which CDI doesn't have</a>:</p> <blockquote> <p>Also the combination <code>@Named @ViewScoped</code> won't work as intended. The JSF-specific <code>@ViewScoped</code> works in combination with JSF-specific <code>@ManagedBean</code> only. Your CDI-specific <code>@Named</code> will behave like <code>@RequestScoped</code> this way. Either use <code>@ManagedBean</code> instead of <code>@Named</code> or use CDI-specific <code>@ConversationScoped</code> instead of <code>@ViewScoped</code>.</p> </blockquote> <p>Then</p> <pre><code>@javax.inject.Named @javax.faces.bean.[Cdi]Scoped </code></pre> <p>can be used for CDI beans directly referenced from your JSF pages AFAIK. I haven't had any problems with the above combinations so far, so you could consider <code>@ManagedBean</code> obsolete here.</p> <p>What's left is the service layer, here mostly transactional EJB service beans declared as</p> <pre><code>@javax.ejb.* </code></pre> <p>mostly @javax.ejb.Stateless. You can even annotate and use <a href="http://www.adam-bien.com/roller/abien/entry/ejb_3_1_killed_the" rel="nofollow noreferrer">EJBs directly from JSF pages</a> - though I'm not sure if this design is desirable. To reference (inject) any components annotated with @javax.ejb.*, e.g. <code>@Stateless</code>, prefer <code>@Inject</code> over <code>@EJB</code> <a href="http://www.germanescobar.net/2010/04/4-areas-of-possible-confusion-in-jee6.html" rel="nofollow noreferrer">as described here</a>. (Probably an ancestor of this answer...)</p> <p>Finally, a very nice overview of Java EE 6 annotations can be found here: <a href="http://www.physics.usyd.edu.au/~rennie/javaEEReferenceSheet.html" rel="nofollow noreferrer">http://www.physics.usyd.edu.au/~rennie/javaEEReferenceSheet.html</a></p> <p><strong>Note</strong>: the above info is not from an expert, but simply my own take/sight from a newcomers perspective on this <strong>ridiculously confusing Java EE 6 annotations spaghetti</strong>. More insight has yet to be developed. I hope this answer can endure to be a general, practical answer to this confusion - even though it has gone a little overboard in the context of the original question.</p>
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    1. POAre @ManagedBeans obsolete in JavaEE6 because of @Named in CDI/Weld?
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    1. COyou posted a reply comment which was half decent but then some force took over and you changed it into an insane blob.People are suggesting CDI is replacement over @managed. Question is clear but comparing apples with oranages.
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    2. COYes, kind of. I still have to be convinced how CDI is such a replacement. In the meantime, newcomers are looking for solutions, not 'spec-babble'. They (I) need some help to decide which annotations to use in which situation to get things going. IMHO
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    3. COI think you exactly answered the question as narrowly as possible. In fact, I would like 500 *more* words on this subject...
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