Re: Obtaining class instance of generic quantified type
On Apr 24, 12:13 pm, Rakesh <rakesh.use...@gmail.com> wrote:
Hi -
For a particular method with a signature like this -
class GlobalClass {
public abstract <R> R process(Object obj_, Class<R>
returnType_);
}
I wanted to quantify it with NodeList<Node> .(substitute R with
NodeList<Node> ).
So I tried this one ..
GlobalClass global = ...
Object obj =
NodeList<Node> list = global.process(obj, NodeList.class=
);
That code resulted in warnings.
Doing something like -
NodeList<Node> list = global.proces(obj,
NodeList.class<Node.class> );
results in a compilation error.
What is the correct way of doing this.
There is no object reprepsenting the class NodeList<Node> - only an
object representing the class NodeList. This is one of the many holes
in generics as a consequence of erasure. By the same token, you
cannot reflectively create a NodeList<T> for any T - you can only
create instances of the raw type, NodeList.
In short, you can't get there from here without even more code,
without ignoring Java's type safety rules somewhere.
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