I have the following custom iterator:
class PetIterator<T extends Pet> implements Iterator<T>
I have this class:
class Dog extends Pet
But the Java compiler won't allow this cast (iterate returns a PetIterator):
Iterator<Dog> dogs = (Iterator<Dog>)petstore.iterate (“dogs”);
How can I retrieve my Golden Retrievers, other than writing:
PetIterator dogs = petstore.iterate (“dogs”);
...
Dog dog = (Dog)dogs.next();
You could rewrite your iterate(String) method to this:
class PetStore {
<T extends Pet> PetIterator<T> iterate(Class<T> clazz);
}
Then you could use that method type-safely
PetIterator<Dog> dogs = petstore.iterate (Dog.class);
// ...
Dog dog = dogs.next();
Because PetIterator<T extends Pet> is not a PetIterator<Dog>. It can be any Pet, and then your iterator.next() will fail to cast to Dog.
Why don't you simply use class PetIterator implements Iterator<T> (which is the same T is the one in the petstore object, which I guess is also generic)
