@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 testSave() {

    Product product = new Product();
    product.setProductname("华为平板电脑");
    product.setPrice(78.0f);
    product.setDescption("华为平板电脑");

    Category category = categoryService.findById(7);

    /*Category category=new Category();
    category.setCategoryname("平板");*/

    product.setCategory(category);

    productService.save(product);
  }