About CDI Managed Beans

A managed bean is implemented by a Java class, which is called its bean class. A top-level Java class is a managed bean if it is defined to be a managed bean by any other Java EE technology specification, such as the JavaServer Faces technology specification, or if it meets all the following conditions.

It is not a nonstatic inner class.
It is a concrete class or is annotated @Decorator.
It is not annotated with an EJB component-defining annotation or declared as an EJB bean class in ejb-jar.xml.
It has an appropriate constructor. That is, one of the following is the case.
- The class has a constructor with no parameters.
- The class declares a constructor annotated @Inject.

No special declaration, such as an annotation, is required to define a managed bean.