    @Test
    public void testInsert() throws IOException {

        tree.insert(1L, 1L);
       
        Assert.assertNotNull(tree.getRoot());
        
        Assert.assertArrayEquals(new Long[]{1L}, tree.getRoot().getKeys());
        Assert.assertArrayEquals(new Long[]{1L}, tree.getRoot().getValues());
        
        tree.insert(3L, 3L);
        tree.insert(2L, 2L);
        tree.insert(4L, 4L);
        
        Assert.assertArrayEquals(new Long[]{1L, 2L, 3L, 4L}, tree.getRoot().getKeys());
        Assert.assertArrayEquals(new Long[]{1L, 2L, 3L, 4L}, tree.getRoot().getValues());

        tree.insert(5L, 5L);        
        
        Assert.assertArrayEquals(new Long[]{3L}, tree.getRoot().getKeys());
        Assert.assertArrayEquals(new Long[]{1L,2L,3L}, tree.getRoot().getPointers()[0].getKeys());
        Assert.assertArrayEquals(new Long[]{1L,2L,3L}, tree.getRoot().getPointers()[0].getValues());
        
        Assert.assertArrayEquals(new Long[]{4L,5L}, tree.getRoot().getPointers()[1].getKeys());
        Assert.assertArrayEquals(new Long[]{4L,5L}, tree.getRoot().getPointers()[1].getValues());          
    }