Create generic list, whereby type of the list known only at runtime

Question

I want to generate a generic list where the type of the list is known only at runtime (its the type of the object, which create that list).

Complete description:

I want to implement this functionality in a abstract class, so i know the parent class before runtime.

Don't know how to do that.

    Class myClass = getClass().getSuperclass();
    LinkedList<myClass> list = new LinkedList<myClass>();

does not work. Any ideas?

Answer 1

或者你可以写：

    List<Object> list = new LinkedList<Object>();

Answer 2

Generics are largely a compile time feature so it doesn't have any meaning in this context.

You can just write

List list = new LinkedList();

I usually prefer ArrayList if you can use that. ;)

Answer 3

Simply use Non-Generics ArrayList

ArrayList arrList = new ArrayList();

even you can use the <?>

Thought using the List will be good, as it show the principle of "Program in Interface rather than implementation"

Answer 4

Another option would be to parametrize the abstract class with the type of the extending class. This is a bit over-engineered, but should work:

package test;

import java.util.ArrayList;
import java.util.List;

public class  AbstractListHolder<T> {

    private List<T> list = new ArrayList<T>();

    List<T> getList() {
        return list;
    }

}

class ListHolder extends AbstractListHolder<ListHolder> {

    void doSomething() {
        getList().add(this);        
    }

}