import java.util.List;
public class WildcardErrorBad {
void swapFirst(List l1, List l2) {
Number temp = l1.get(0);
l1.set(0, l2.get(0)); // expected a CAP#1 extends Number,
// got a CAP#2 extends Number;
// same bound, but different types
l2.set(0, temp); // expected a CAP#1 extends Number,
// got a Number
}
}