Integer/ int autoboxing query with generic functions in Java

Okay, so I am trying to write a generic sorting package in Java (I'm taking an algorithms course and I see it as good practice, both in the algorithmic sense and in Java as I'm very new to the language). Anyway, I figure the best way to do this is to create a Sort class with multiple sorting methods within, such as insertionSort, mergeSort etc. If you feel there's a better way of doing this, please let me know as a comment as I am always open to suggestions for writing cleaner and more efficient code.

As for the question:

I have the backbone structure down and want to try coding the insertionSort method first. However, I have tried to pass it an integer array but am getting some problems. Firstly, with generics I understand that you have to use <Integer> as opposed to <int>, but for some reason if I create an array such as int[] arr = new int[]{..} and pass this in to the generic it does not work. How do I fix this without using Integer[] arr = new Integer[]{..}? I was under the impression that the compiler would box my int to Integer automatically?

My code:

public class Sort<T> {
    public T[] insertionSort(T[] array) {
        // do some stuff
        return array;
    }

    public static void main(String[] args) {
        int[] orig = new int[]{1,35,3,2,4634,2,46,7,33,56};
        Sort<Integer> sorter = new Sort<Integer>();
        sorter.insertionSort(orig);
    }
}