Java – pass the parameterized class instance to the constructor

I have lost my way through the jungle, please help me:) I have such a thing:

public class BaseClass<TYPE> {
    public BaseClass(Class<TYPE> clazz) {};
}

public class FirstLevelClass<REFRESHABLE 
    extends RefreshableInterface> extends BaseClass<REFRESHABLE> {

    public FirstLevelClass(Class<REFRESHABLE> clazz) {
        super(clazz);
    };
}

public class Argument<T extends AnyOtherClass> 
    implements RefreshableInterface {

    public refresh() {}
}

pulbic class ProblematicClass 
    extends FirstLevelClass<Argument<AnyOtherClassDescendant>> {

    public ProblematicClass() {
        //Compiler error: Constructor 
        //FirstLevelClass<Argument<AnyOtherClassDescendant>>(Class<Argument>) is undefined
        super(Argument.class); 
    }
}

As far as I know, the compiler should accept parameters because it implements refreshableinterface

>Why did I get this error? > How to make problem work?

PS: if you have a better title, please change it I can't make up for it better

Solution

The problem is that your constructor expects class < T >, and T in your code is inferred as argument < anyotherclassdescendant >

Therefore, you should pass a class < argument < anyotherclassdescendant > >, and you are passing class & argument > However, you cannot directly pass this class instance because you cannot execute argument < anyotherclassdescendant > class.

However, you can solve the problem by converting the class type to the desired instance:

public ProblematicClass() {
    super((Class<Argument<AnyOtherClassDescendant>>)(Class<?>)Argument.class); 
}

Notice how you type the class < argument > first to class < >, and then classify the result type to class < argument < anyotherclassdescendant > > There is no easy way to do this

The reason for this is that for all parameterized instantiations of a generic type, there is only one class instance associated with the class itself A single compilation unit of a common type is only compiled into a single class file I guess the C implementation template is different You can get different machine code in different instances

Therefore, if you execute the following code, you will get true as the output:

List<String> strList = new ArrayList<String>();
List<Integer> intList = new ArrayList<Integer>();

boolean isSameClassInstance = strList.getClass() == intList.getClass();
System.out.println(isSameClassInstance);