Dependency Injection: Diagnostics for bean class of generic or parameterized type

[KidoVin01]

Managed Beans

If the managed bean class is a generic type, it must have scope @dependent. If a managed bean with a parameterized bean class declares any scope other than @dependent, the container automatically detects the problem and treats it as a definition error.

Diagnostics

1. Check if class is a managed bean
2. Check if managed bean is of generic/parameterized type
3. Check if dependency class is annotated with @Dependent or has no other scope specified
4. If not, deliver an error at the class declaration

Quickfixes

• Suggest removing scope

Example

@ApplicationScoped
// Error here due to the generic type
public class Greeting<T>{
	public String greet(String name) {
        return "GreetingA, " + name;
    }
}

[INFO] [ERROR   ] CWWKZ0004E: An exception occurred while starting the application demo-servlet. The exception message was: com.ibm.ws.container.service.state.StateChangeException: org.jboss.weld.exceptions.DefinitionException: WELD-000071: Managed bean with a parameterized bean class must be @Dependent: class io.openliberty.sample.jakarta.di.error.generic.Greeting

Related to #153

[KidoVin01]

Working on this

[kathrynkodama]

1. Identify @Inject field/method/constructor
2. Check if dependency class is a generic/parameterized type
3. Check if dependency class is annotated with @Dependent or has no other scope specified
4. If so, deliver an error at the class declaration

Is step (1) really needed to check for this diagnostic? If not let's remove it

[KidoVin01]

I have updated the diagnostics accordingly.