Java List toArray(T[] a) implementation

Question

I was just looking at the method defined in the List interface:

Returns an array containing all of the elements in this list in the correct order; the

Answer 1

Most likely this is to allow you to reuse arrays, so you basically avoid (relatively costly) array allocation for some use cases. Another much smaller benefit is that caller can instantiate array slightly more efficiently, since toArray() must use 'java.lang.reflect.Array.newInstance' method.