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

Which of the following is true about LinkedList regarding its functionalities?

1. It's designed for rapid random access

2. It's optimized for sequential access

3. It can't be used to implement a stack or queue

4. It keeps elements in sorted order

The correct answer is: It's optimized for sequential access

LinkedList is optimized for sequential access, meaning that it is most efficient when elements are accessed in a specific order. This is because LinkedList stores elements as individual nodes with pointers to the next node, allowing for quick insertion and deletion of elements. Option A is incorrect because it is referring to an array, which is designed for rapid random access as elements can be accessed at any position. Option C is incorrect because LinkedList can be used to implement both a stack and a queue, as it supports operations for adding and removing elements at either end. Option D is incorrect because LinkedList does not inherently keep elements in sorted order, it would require additional logic or a custom implementation to do so. Thus, the correct answer is B as it describes one of the main functionalities of a LinkedList data structure.