• @Model = @Named + @RequestScoped
  • The @Named annotation just makes it possible to reference the bean from the EL
  • it isn’t necessary to create a getter or setter method to inject one bean into another. CDI can access an injected field directly (even if it’s private!)
  • Bean could be invoked by Unified EL.
  • A bean type is a user-defined class or interface.
  • Bean types may be restricted to an explicit set by annotating the bean with the @Typed annotation
  • If an injection point does not explicitly specify a qualifier, it has the default qualifier, @Default.
  • Don’t assign a scope other than @Dependent to an entity class
  • @Produces used in factory method.
  • @Alternative usually used in testing and must be enabled by config

Fixing unsatisfied and ambiguous dependencies

To fix an unsatisfied dependency, either:

  • create a bean which implements the bean type and has all the qualifier types of the injection point,
  • make sure that the bean you already have is in the classpath of the module with the injection point, or
  • explicitly enable an @Alternative bean that implements the bean type and has the appropriate qualifier types, using beans.xml.

To fix an ambiguous dependency, either:

  • introduce a qualifier to distinguish between the two implementations of the bean type,
  • disable one of the beans by annotating it @Alternative,
  • move one of the implementations to a module that is not in the classpath of the module with the injection point, or
  • disable one of two @Alternative beans that are trying to occupy the same space, using beans.xml.

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