When to use a List over an Array in Java?

Question

In Java, when would it be preferential to use a List rather than an Array?

Answer 1

Rules of thumb:

• Use a List for reference types.
• Use arrays for primitives.
• If you have to deal with an API that is using arrays, it might be useful to use arrays. OTOH, it may be useful to enforce defensive copying with the type system by using Lists.
• If you are doing a lot of List type operations on the sequence and it is not in a performance/memory critical section, then use List.
• Low-level optimisations may use arrays. Expect nastiness with low-level optimisations.