@Test
 public void testUpdate() {
   Product product = productService.findById(16);
   product.setProductname("平凡的世界-贾平凹");
   product.setDescption("平凡的世界-贾平凹");
   productService.update(product);
 }
  @Test
  public void testDelete() {

    Product product = productService.findById(29);
    productService.delete(product);
  }