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

What feature does an ArrayList have over an array?

1. It can only store primitive types

2. It has a fixed length

3. It can automatically resize itself

4. It is more memory efficient than an array

The correct answer is: It can automatically resize itself

An ArrayList has the advantage of being able to automatically resize itself while an array has a fixed length. This means that an ArrayList can grow or shrink as needed, making it more flexible and convenient for storing and managing collections of data. Option A is incorrect because an ArrayList can also store non-primitive types, such as strings or objects. Option B is incorrect because an ArrayList's length is not fixed. Option D is incorrect because an array is actually more memory efficient than an ArrayList as it does not have the overhead of automatic resizing.