[ISSUE] CrudRepository save() Method issue

[YinMinghhh]

Hello, there may be a bug.

This article reads "So, any change to that entity will be automatically persisted in the database, regardless of whether we are invoking the save() method." and gave such an example:

@Test
@Transactional
public void shouldUpdateExistingEntryInDBWithoutSave() {
    MerchandiseEntity pants = new MerchandiseEntity(
      ORIGINAL_TITLE, BigDecimal.ONE);
    pants = repository.save(pants);

    Long originalId = pants.getId();

    // Update using setters
    pants.setTitle(UPDATED_TITLE);
    pants.setPrice(BigDecimal.TEN);
    pants.setBrand(UPDATED_BRAND);

    Optional<MerchandiseEntity> resultOp = repository.findById(originalId);

    assertTrue(resultOp.isPresent());
    MerchandiseEntity result = resultOp.get();

    assertEquals(originalId, result.getId());
    assertEquals(UPDATED_TITLE, result.getTitle());
    assertEquals(BigDecimal.TEN, result.getPrice());
    assertEquals(UPDATED_BRAND, result.getBrand());
}

I found that the test did pass, but findById() simply reads data from the cache, and the data in the database is not updated because save() is not called.

If the cache is cleared between save() and findById() (e.g. by calling entityManager.clear()), the test cannot pass.

So the statement in the article is not quite correct.