Suppose that for some interface type I, the method signature was rewritten as follows: void printAll(List<? extends I> list); Explain, without simply reusing the word “extends”, what property this new signature now enforces upon the parameters with which the method printAll is called. Include in your answer a possible situation in which this restriction will be useful by suggesting a possible interface I.

The new method signature, void printAll(List<? extends I> list), enforces a restriction on the type of objects that can be passed as arguments to the method. Specifically, the method can only accept a List of objects that are either of type I or its subtypes.

This restriction can be useful in situations where you want to ensure that the objects in the List are all of a certain type or its subtypes. For example, suppose you have an interface I called Animal, which has two subtypes: Cat and Dog. You could write a method that accepts a List of either Cats or Dogs:

void printAll(List<? extends Animal> list) {
  for (Animal animal : list) {
    System.out.println(animal.getName());
  }
}

This method will only accept a List of Cats or Dogs, but not a List of other Animals such as Birds. This ensures that the method can only be called with a List of the appropriate type, preventing potential errors at runtime.