Wildcards

You are invited to Pie company that succeeds in baking and packing Pies. Their current infrastructure is described in the code:

// Different Bakeries that should be packed to Box'es and delivered to customers
class Bakery {}

class Cake extends Bakery {}

class Pie extends Bakery {}

class Tart extends Bakery {}

// This (of course) can be packed in a box, but we want to disable its delivery to customers
class Paper {}

// Implementing class exists that is used to pack everything
interface Box<T> {
    public void put(T item);
    public T get();
}

Now they decided to deliver bakeries to the customers and ask you to design the Deliveryman class. The delivery men should succeed in the following:

• Deliver Bakery or any subclass of it, packed into boxes
• Do not deliver anything else (e.g. Paper)
• Prohibit Deliveryman to put anything into the Box inside deliver method at a compile time by raising errors or warnings.

Your task is to create a method signature leaving implementation unchanged. The Deliveryman template follows:

public class Deliveryman {
   // Method to change signature of
   public void deliver(Box box) {
     // He knows how to do this, leave unchanged
   }
   
}

So, instead of public void deliver(Box box) write the line that replaces it in the field below.