Question: ArrayList vs. LinkedList

Answer: The List interface defines an ordered collection of elements. Available implementations include ArrayList and LinkedList, where both implement the List interface. When your program needs to work with a List, it should not care if it is an ArrayList or a LinkedList, only that whatever class is used provides a known behavior. That behavior is the interface.

If your program frequently provides random access to the data of the list, the ArrayList class offers quick access to individual elements of the list. This quick access comes at a cost of slower operations for adding and removing in the middle of the list.
If this latter behavior is what you desire, than the LinkedList class offers a better alternative. It provides quick sequential access, additions, and deletes, at a cost of slower random access.

This tip is based on Sun’s newsletter
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