get a class instance of generics type T

Question

I have a generics class, Moo<T>. In a method of Moo,  get the class instance of type T, but I just can't call T.class.

What is the preferred way to get around it using T.class?

Answer 1

The short answer is, that there is no way to find out the runtime type of generic type parameters in Java.

A  solution to this is to pass the Class of the type parameter into the constructor of the generic type, e.g.

class Moo<T> {
    final Class<T> typeParameterClass;

    public Moo(Class<T> typeParameterClass) {
        this.typeParameterClass = typeParameterClass;
    }

    public void bar() {
        // you can access the typeParameterClass here and do whatever you like
    }
}