How to increase the size of an array in Java?

Question

I want to store as many elements as desired by the user in an array. But how do I do it.

If I were to create an array, I must do so with a fixed size. Every time a

Answer 1

On a low level you can do it this way:

long[] source = new long[1];
long[] copy = new long[source.length + 1];
System.arraycopy(source, 0, copy, 0, source.length);
source = copy;

Arrays.copyOf() is doing same thing.