Array or List in Java. Which is faster?

Question

I have to keep thousands of strings in memory to be accessed serially in Java. Should I store them in an array or should I use some kind of List ?

Since arrays keep

Answer 1

It you can live with a fixed size, arrays will will be faster and need less memory.

If you need the flexibility of the List interface with adding and removing elements, the question remains which implementation you should choose. Often ArrayList is recommended and used for any case, but also ArrayList has its performance problems if elements at the beginning or in the middle of the list must be removed or inserted.

You therefore may want to have a look at http://java.dzone.com/articles/gaplist-%E2%80%93-lightning-fast-list which introduces GapList. This new list implementation combines the strengths of both ArrayList and LinkedList resulting in very good performance for nearly all operations.