Mastering Java: The Ultimate Quiz for 'Thinking in Java'

Why are unbounded wildcards considered safer than raw types?

1. They perform automatic casting to the Object type

2. They ensure type safety by enforcing stronger compile-time checks

3. They prevent addition of new elements to the collection

4. Unbounded wildcards and raw types have the same level of safety

The correct answer is: They ensure type safety by enforcing stronger compile-time checks

Unbounded wildcards are considered safer than raw types because they enforce stronger type checks at compile-time, while raw types do not. Raw types allow any type of object to be added to a collection, potentially leading to type errors at runtime. Unbounded wildcards, on the other hand, restrict the types that can be added to a collection, ensuring type safety. Options A, C, and D are incorrect because - Option A is incorrect because unbounded wildcards do not perform automatic casting to the Object type. In fact, they do not perform any casting at all, as they only restrict the types that can be added to a collection. - Option C is incorrect because unbounded wildcards do not prevent addition of new elements to the collection. They only prevent addition of elements of incompatible types. - Option D is incorrect because unbounded wildcards and raw types do not have the same level