How can i get class of Generic parameter

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get type of a generic parameter in java with reflection
How to get generic’s class

How can i get class of Generic parameter.

 public <T extends BeanProxiable> void method(){
    Class claz = T.class
 }

It's wrong. Why? How to solve this problem?

you can find the answer here - http://stackoverflow.com/questions/1901164/get-type-of-a-generic-parameter-in-java-with-reflection — Subhrajyoti Majumder, Nov 20 '12 at 07:27
http://stackoverflow.com/questions/2223233/how-to-get-generics-class — Vikdor, Nov 20 '12 at 07:28
your method that returns an object that extends class `BeanProxiable` then why do u need that class reference here ? — vels4j, Nov 20 '12 at 07:30

score 2 · Answer 1 · answered Nov 20 '12 at 07:28

2

You can't.

T's type is only known at compile time.

Once the program starts to run, T's type will be Object.

This is how generics work in Java.

answered Nov 20 '12 at 07:28

jahroy

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score 1 · Accepted Answer · answered Nov 20 '12 at 07:28

You can provide the type dynamically, however the compiler doesn't do this for you automagically.

public abstract class LastActionHero<H extends Hero>(){
    protected final Class<H> hClass;
    protected LastActionHero(Class<H> hClass) {
        this.hClass = hClass;
    }
    // use hClass how you like.
}

BTW: It not impossible to get this dynamically, but it depends on how it is used. e.g

public class Arnie extends LastActionHero<MuscleHero> { }

It is possible to determine that Arnie.class has a super class with a Generic parameter of MuscleHero.

public class Arnie<H extend Hero> extends LastActionHero<H> { }

The generic parameter of the super class will be just H in this case.

How can i get class of Generic parameter

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