Thread: Generics and Dynamic Instantiation Problem

Can anyone help me to fix the code in the Main so that is works as intended?
Gurus will know what I'm after.
TIA

Please see below:

public abstract class MyBaseElement 
{...}
 
public class MyElementA extends MyBaseElement
{...}
 
public class MyElementB extends MyBaseElement
{...}
 
public class MyElementC extends MyBaseElement
{...}
 
public interface Mapper<T>
{...}
 
public class MyMapperA implements MyMapper<MyElementA>
{...}
 
public class MyMapperB implements MyMapper<MyElementB>
{...}
 
public class MyMapperC implements MyMapper<MyElementC>
{...}

// this method returns an instance of
// one of the child classes: MyElementA, MyElementB, MyElementC, etc...

public MyBaseElement getSpecificElement() {...}

// this method returns a specific mapper based on the element

public Mapper<? extends MyBaseElement> getSpecificMapper(MyBaseElement element)
{
    if (element instanceof MyElementA) return new MyMapperA;
    if (element instanceof MyElementB) return new MyMapperB;
    if (element instanceof MyElementC) return new MyMapperC;
    ...
}

// Main
 
...
 
MyBaseElement element = getSpecificElement();
 
// the line below compile
Class<? extends MyBaseElement> myElement = element ;
 
//the line below does not compile: can not convert from MyBaseElement to Mapper<? extends MyBaseElement>
// Any ideas, please?
Mapper<? extends MyBaseElement> myMapper = getSpecificMapper(myElement ) 
 
myMapper.doStuff();
 
...
 
// end-Main

I agree with JavaPF here, somewhat confusion this.

However, I'm not sure this will work, into the method getSpecificMapper you're passing in a Class<? extends MyBaseElement> but in the method signature it takes a MyBaseElement, not a Class.

// Json