Get class of generic

java class generics types parameterized
user321068 picture user321068 · Mar 25, 2011 · Viewed 13.1k times · Source

My class starts with

public abstract class LastActionHero<H extends Hero>(){

Now somewhere in the code I want to write H.class but that isn't possible (like String.class or Integer.class is).

Can you tell me how I can get the Class of the generic?

Answer

kospiotr picture kospiotr · Nov 5, 2011

We do it in the following way:

    private Class<T> persistentClass;

    public Class<T> getPersistentClass() {
        if (persistentClass == null) {
            this.persistentClass = (Class<T>) ((ParameterizedType) getClass().getGenericSuperclass()).getActualTypeArguments()[0];
        }
        return persistentClass;
    }

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