Java约束违规和HIbernate验证不会在更新时解决

Question

I have a domain object which looks like below

@Entity
@Table(name = "zone")
public class Zone {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    long id;

    @Column(unique=true, nullable=false)
    String uuid;

    @NotNull
    @Size(min=1)
    @Column(unique=true, nullable=false)
    String name;

    @NotNull
    @Size(min=1)
    @Column(nullable=false)
    String admin;
}

There are two service calls which save and update the Zone objects

@Override
public Zone create(Zone zone) {

    if((zone.getUuid()==null)||(zone.getUuid().isEmpty())){
        String uuid = UUID.randomUUID().toString();
        zone.setUuid(uuid);
    }
    zoneRepository.save(zone);
    return zone;
}

@Override
public Zone update(Zone zone) {
    zoneRepository.save(zone);
    return zone;
}

Zone repository extends JPA Repository of spring-data framework

public interface ZoneRepository extends JpaRepository<Zone, Long>

I am using unit test cases to test the two services

@Test(expected=ConstraintViolationException.class)
public void createZoneWithBlankName(){
    Zone zone = new Zone();
    zone.setName("");
    zone.setAdmin("Admin");
    zoneService.create(zone);
} 

This test case is throwing ConstraintViolationException as expected when name is blank. But when I am updating a already existing zone with a blank name, no ConstraintViolationException is thrown and the test case below fails

@Test(expected=ConstraintViolationException.class)
public void updateZoneWithBlankName(){
    Zone zone = new Zone();
    zone.setName("Zone");
    zone.setAdmin("Admin");
    zoneService.create(zone);
    Assert.assertTrue(zone.getId() != 0);

    long id = zone.getId();
    String newZoneName = "";
    String newAdmin = "New Admin";

    Zone zoneToUpdate = new Zone();
    zoneToUpdate.setId(id);
    zoneToUpdate.setName(newZoneName);
    zoneToUpdate.setAdmin(newAdmin);

    zoneService.create(zoneToUpdate);

}

If I set the id of "zoneToUpdate" object to any value other than the existing id, then the constraint violation is thrown. Which indicates that the exception is thrown only for creating new objects and not for updating the existing ones.

Answer 1

The reason you are not seeing the exceptions for updates is that the current unit of work is not getting flushed to the underlying database.

And that's to be expected: that's how the 1st-level cache works in Hibernate and JPA.

For details, search for the "false positives" tip in the Testing chapter of the Spring Reference manual .

Regards,

Sam ( author of the Spring TestContext Framework )