Generics, factories and reflection
Hi.
I have a problem with a factory method. This method should create
instances of the collection framework. The simplest implementation
looks like this:
--------------------------------------------------------------
public static List<E> createList() {
return new ArrayList<E>();
}
List<String> l1 = createList();
--------------------------------------------------------------
But in my special case, I want to (and have to) pass the implementing
class as an argument. So the factory could create instances of
ArrayList but also of LinkedList. The following method compiles without
warnings and errors:
--------------------------------------------------------------
public static List<E> createList(Class<? extends List<E>> listImpl) {
try {
List<E> l = listImpl.newInstance();
return l;
}
catch (Exception dontBotherMe) {
return null;
}
}
--------------------------------------------------------------
But how can I call this method?
List<String> l2 = createList(ArrayList.class)
does not work, because "Class<ArrayList>" does not match
"Class<List<E>>".
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