Is @javax.faces.bean.ManagedBean Dead on Arrival?

Java EE 6 has three different ways of defining “beans” that are “managed” in one way or another. Here is a quick recap. JSR 314 JSF 2.0 introduced annotations to avoid the tedium of declaring managed beans in faces-config.xml: @javax.faces.bean.ManagedBean(name="user") @javax.faces.bean.SessionScoped public class UserBean implements Serializable { ... } That's certainly nicer than user com.corejsf.UserBean session There is a second annotation for a rudimentary dependency injection mechanism: public class EditBean { @javax.faces.bean.ManagedProperty(value="#{user}") private UserBean currentUser; } When an EditBean instance is constructed, the value expression #{user} is evaluated, and the result is passed to the setCurrentUser method (which you must also supply) (It is a bit odd that the @ManagedProperty annotation is applied to a field when in fact the property setter is invoked. That is not how injection works elsewhere in Java EE. Let's not dwell on this oddity.) JSR 316 There is an annotation @javax.annotation.ManagedBean, defined by JSR 316, that attempts to generalize JSF managed beans for use elsewhere in Java EE. There isn't much there. You can use the @PostConstruct and @PreDestroy annotations. You can use @Resource for injecting EE resources. You can use interceptors. For example, if you define @javax.annotation.ManagedBean("user") public class UserBean ... ...

Date: December, 23 2009
Url: http://www.java.net/blog/cayhorstmann/archive/2009/12/23/javaxfacesbeanmanagedbean-dead-arrival

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