integer to arraylist java code example

Example 1: convert list of integer to array in java

List<Integer> al = new ArrayList<Integer>(); 
Integer[] arr = new Integer[al.size()]; 
arr = al.toArray(arr);

Example 2: convert array of int to arraylist java

int[] ints = {1, 2, 3};
List<Integer> intList = new ArrayList<Integer>(ints.length);
for (int i : ints)
{
    intList.add(i);
}