@Test

void optimisticLockError() {

​

    // Store the saved entity in two separate entity objects

    ProductEntity entity1 = 

    repository.findById(savedEntity.getId()).get();

    ProductEntity entity2 = 

    repository.findById(savedEntity.getId()).get();

​

    // Update the entity using the first entity object

    entity1.setName("n1");

    repository.save(entity1);

​

    //  Update the entity using the second entity object.

    // This should fail since the second entity now holds an old version 

    // number, that is, an Optimistic Lock Error

    assertThrows(OptimisticLockingFailureException.class, () -> {

      entity2.setName("n2");

      repository.save(entity2);

    });

​

    // Get the updated entity from the database and verify its new state

    ProductEntity updatedEntity = 

    repository.findById(savedEntity.getId()).get();

    assertEquals(1, (int)updatedEntity.getVersion());

    assertEquals("n1", updatedEntity.getName());

}

​