Cannot resolve JvmTypeReference - xtext

I am using XText to create a DSL that works with Java classes. I have created a metamodel that includes a JvmTypeReference to an existing Java class (I am only interested in classes, but I have tried JvmType and JvmGenericType, to no avail). In the validator (whose supertype is XbaseValidator) I can resolve these references to LightweightTypeReferences and then access their attributes that way (supertype, qualifiedName, etc). However, at no other point in the code can I do the same, i.e. resolve JvmTypeReference to a useful resource, because I have no access to the XbaseValidator methods.
What is the intended way of using JvmTypeReferences anywhere other than in a subclass of XbaseValidator?

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Using the analyzer package, is it possible to create an instance of a DartType representing a would-be generated code?

While using the analyzer package, I was wondering if it was possible to create an instance of its DartType object.
The issue I'm facing is, the analyzer output doesn't give me a valid DartType for a given class because that class has yet to exist (it is not yet generated by a code-generator).
I can work around not using DartType directly and instead make some copycat class. But that adds a lot of complexity. So I'd like to be able to create a DartType representing the would-be generated class.
I've looked into the TypeSytem/TypeProvider objects which seem to object type-related utilities but didn't find anything I wanted.
Is that possible?

Upgrading from Play 2.6 to 2.7: How to refactor this Play.current statement to use DI

In my Java 8 Play 2.6 application I have this particular line in a MessageConsumer class that reads a "Rule" record in the DB and sends the JSON message (node) to a specific processor based on the type configured on the rule column. ProcessType is an enum of Sub Classes that all extend from a base (Super class) process.
Play.current().injector().instanceOf(ProcessType.getClass(matchingRule.getProcessType())).processMessage(node, matchingRule);
I'm having trouble figuring out how to refactor this and don't want to add the allowGlobalApplication = true config parameter if I can avoid it.
The most straightforward approach is to inject the Injector into the component that contains this call (the MessageConsumer). This can be done the same way as any other Play component.
You can also inject the Application instance, which would return the same thing as Play.current(). This could be useful if you need more information from the Application object, but if not, injecting the Injector directly would be preferable, as it would create less coupling between the MessageConsumer and other components.
This assumes that the MessageConsumer is created by DI itself. If not, please add more details to the question, including the context code.

What its the first, the annotated class (egg) or used class (chicken)?

certainly I have not read something fundamental, and it seems very strange, but I wonder.
Suppose you use
#SharedPref
public interface SharedPreferencesInterface {
#DefaultBoolean(true)
boolean showDeviceName();
I have the IDE (idea) configured with Gradle, and I generated the SharedPreferencesInterface_ class that I can use in another class as
#Pref
SharedPreferencesInterface_ prefs;
But suppose someone now download the project, how can the use? Because the class where used SharedPreferencesInterface_ not compile because the class does not exist, and the class does not exist because compilation errors ...
How it's made? Surely there is a way ... configured to compile certain classes first?
Help is appreciated.
A greeting.
But suppose someone now download the project, how can the use? Because
the class where used SharedPreferencesInterface_ not compile because
the class does not exist, and the class does not exist because
compilation errors ...
This is the same situation when you compile a project in a full build (when no classes are generated yet). Actually Gradle always does a full build currently in Android projects. No configuration is needed at all in addition to the standard AndroidAnnotaions config.
Actually this works because the compiler does not fully compiles your class before passing it to annotations processing. It is clear it should not to, because the class may reference generated classes, which are only available after the processing. So first the compiler creates a model of the classes, only parses the structure of the them (fields, methods, return types, parameter types, etc), but not the implementations. Also it allows missing types even on fields. If it finds a missing type, it assigns to TypeKind.ERROR, but the name of the type is still available for the annotation processor. After the processor is done, it generates the missing class, so the kind of the class is no longer TypeKind.ERROR, and the compilation can succeed.

Which interface/abstract class is for grails Domain class behaviour?

I have a generic method for doing a common operation on many domain class
static Map getNumberOfPropertyByTopicIds(def criteriaClass, List ids) {
criteriaClass.createCriteria(). //Some GORM methods used
}
I wanted autocomplete on various things applied on criteriaClass. But for doing that I need to replace def criteriaClass to InterfaceForDomainClassBehaviour criteriaClass.
But I don't know InterfaceForDomainClassBehaviour is what. Which interface/abstract class implements Domain class behaviour?
There isn't one.
Grails uses "convention over configuration", so unlike other frameworks where you extend a base class, implement one or more interfaces, use annotations, etc., you simply put your artifact classes (domain classes, services, etc.) in the correct directory under grails-app, use the appropriate class naming convention (except for domain classes), and Grails mixes in behavior for you. You can configure things of course, e.g. with the mapping block, etc.
Before Grails 2 adding methods was mostly done using Groovy runtime metaprogramming, and in Grails 2 most of the behavior is added at compile time using ASTs, and runtime metaprogramming is used mostly for dynamic code like findAllByHeightAndWeightAndHairColorAndShoeSize where it would be impractical and/or impossible to compile in every combination.
Over 100 methods are added to domain classes (decompile some - it's pretty amazing to see how much ends up in your classes considering how small the Groovy source is) and dozens are added to controllers. But this is all mixed in, so although there is significant overlap between your domain classes, there's no common base class or interface unless you add them yourself.

I found the ComClass, now how do I reference it?

I've written a small COM Server in Delphi 2010 that acts as a plug-in into a retail application. The retail application looks for a "discover" interface which registers any number of additional interfaces calling TAutoObjectFactory.Create for each one. This is working just fine--all the plug-in interfaces function as designed.
But now I'd like to call a public method of one interface from another interface so I don't have to duplicate code. Seems simple enough, just call ComClassManager.ForEachFactory looking for the ClassID of the interface I need to use. Got that working, too!
But now that I found the class, I'm stumped by a seemingly trivial final step: how to use or cast the class (or class reference?) I've located to actually call one of its methods.
In the "FactoryProc" I've sent to ForEachFactory, I assume the ComClass property of TComObjectFactory is what I'm after, but it's of type TClass, a class reference to the actual class object to which it points (at least I hope I'm understanding this correctly). I'm a little fuzzy on class references and my attempts to cast or otherwise de-reference this property has resulted in access violations or compiler errors.
Any suggestions?
You're right in your comment, ComClassManager deals with classes, not instances. What you need is (your application-local implementation of) running object table (or something similar), so plugin instances can interact with each other.
How to actually implement it depends on what you really need, e.g. call methods on all running instances, or only on instances of specific classes.

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