@Test public void testIntersection() { int[] arr1 = new int[]{ 0, 1, 2, 3, 4, 5 }; int[] arr2 = new int[]{ 2, 5, 7, 8 }; int[] inter = ArrayUtils.intersection(arr1, arr2); assertEquals(2, inter.length); assertEquals(2, inter[0]); assertEquals(5, inter[1]); arr1 = new int[]{}; inter = ArrayUtils.intersection(arr1, arr2); assertEquals(0, inter.length); }