I find myself in a situation where it seems I would need to be able to cast an Object that is an array of some other, non-primitive type, into its concrete array type, to pass to a generic.
The same thing is trivial to get to work with non-array types: desiredType.cast(o)
yields an object of the correct type.
Would someone be so kind to explain either how to do this with arrays, OR why this would never work?
A demonstration of what I'm attempting to do: import java.lang.reflect.Array; import java.util.Arrays;
public class Main
{
public static <T> void testT(T o)
{
System.out.println("testT called with " + o + " (" + o.getClass() + ")");
}
public static void test(Object o)
{
testT(o.getClass().cast(o));
}
public static void main(String[] args) throws ClassNotFoundException
{
test(new Integer(5));
Class<?> type = Class.forName("java.lang.Integer");
Object array = Array.newInstance(type, 2);
Class<?> arrayType = array.getClass();
Object[] copy = Arrays.copyOf(arrayType.cast(array), Array.getLength(array)); // NOPE. (casting is optional)
System.out.println(copy);
}
}
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