This should be an easy way to do.
int a[] = {3, 10, 4, 2, 8};
int[] b = {10, 4, 12, 3, 23, 1, 8};
List aList = Arrays.asList(a);
List bList = Arrays.asList(b);
aList.retainAll(bList);
System.out.println(" a intersection b "+aList);
int[] c = aList.toArray(new int[0]);