class Pos07 { static class Foo<X extends Number & Comparable<Number>> {} static class DoubleFoo<X extends Number & Comparable<Number>, Y extends Number & Comparable<Number>> {} static class TripleFoo<X extends Number & Comparable<Number>, Y extends Number & Comparable<Number>, Z> {} Foo<?> fw = new Foo<>(); DoubleFoo<?,?> dw = new DoubleFoo<>(); TripleFoo<?,?,?> tw = new TripleFoo<>(); }