How to convert an ArrayList containing Integers to primitive int array?

Question

I\'m trying to convert an ArrayList containing Integer objects to primitive int[] with the following piece of code, but it is throwing compile time error. Is it possible to

Answer 1

It bewilders me that we encourage one-off custom methods whenever a perfectly good, well used library like Apache Commons has solved the problem already. Though the solution is trivial if not absurd, it is irresponsible to encourage such a behavior due to long term maintenance and accessibility.

Just go with Apache Commons