@Test
  public void getProductByUuid() {
    String valid = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa6";
    String invalid = "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb6";
    User user = new User();
    user.setUUID("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa0");
    user.setUsername("koko");

    Product product = dao.getProductByUuid(valid);
    Assert.assertNotNull(product);
    Assert.assertEquals(product.getId().intValue(), 6);

    product = dao.getProductByUuid(invalid);
    Assert.assertNull(product);

    product = dao.getProductByUuid(valid);
    Assert.assertNotNull(product);
    Assert.assertEquals(product.getId().intValue(), 6);

    product = dao.getProductByUuid(null);
    Assert.assertNull(product);
  }