@Test
  public void findsFirstPageOfMatthews() throws Exception {

    Page<Customer> customers = repository.findByLastname("Matthews", new PageRequest(0, 2));

    assertThat(customers.getContent().size(), is(2));
    assertFalse(customers.hasPreviousPage());
  }
  @Test
  public void findsCustomerById() throws Exception {

    Customer customer = repository.findById(2L);

    assertThat(customer.getFirstname(), is("Carter"));
    assertThat(customer.getLastname(), is("Beauford"));
  }
  @Test
  public void findsAllCustomers() throws Exception {

    List<Customer> result = repository.findAll();

    assertThat(result, is(notNullValue()));
    assertFalse(result.isEmpty());
  }