Spring + JPA "Lock wait timeout exceeded; try restarting transaction" - spring

Question

I'm new to Spring and JPA and I encountered the problem specified in the title. To simplify the problem, I have two classes: User and FeedItem. User can have more FeedItems but the relationship is bi-directional (FeedItem knows with which User it's associated). They're both persisted in the database using JPA+Hibernate:
#Entity
#Table
public class User
{
#Id
#GeneratedValue
#Column(name = "id", nullable = false, length = 8)
private int id;
#Column(nullable = false, length = 32, unique = true)
private String alias;
#OneToMany(cascade = CascadeType.ALL, mappedBy = "user")
private List<FeedItem> feedItems = new ArrayList<FeedItem>();
public User()
{
}
public User(String alias)
{
this.alias = alias;
}
... getters/setters...
}
#Entity
#Table
public class FeedItem
{
#Id
#GeneratedValue
#Column(name = "id", nullable = false, length = 16)
private int id;
#Column(nullable = false, length = 64)
private String title;
#ManyToOne
#JoinColumn(name = "userId", nullable = false)
private User user;
public FeedItem()
{
}
public FeedItem(String title, User user)
{
this.title = title;
this.user = user;
}
... getters/setters...
}
The DAOs:
#Repository
public class UserJpaDao implements UserDao
{
private EntityManager em;
#Transactional
public User save(User user)
{
return this.em.merge(user);
}
#Transactional
public void delete(User user)
{
this.em.remove(user);
}
#Transactional(readOnly = true)
public User findById(int id)
{
return this.em.find(User.class, id);
}
#PersistenceContext
void setEntityManager(EntityManager entityManager)
{
this.em = entityManager;
}
}
#Repository
public class FeedItemJpaDao implements FeedItemDao
{
private EntityManager em;
#Transactional
public FeedItem save(FeedItem feedItem)
{
return this.em.merge(feedItem);
}
#Transactional
public void delete(FeedItem feedItem)
{
this.em.remove(feedItem);
}
#Transactional
public FeedItem findById(int id)
{
return this.em.find(FeedItem.class, id);
}
#PersistenceContext
void setEntityManager(EntityManager entityManager)
{
this.em = entityManager;
}
}
This is the test giving the error:
#RunWith(SpringJUnit4ClassRunner.class)
public class FeedItemJpaDaoTest
{
#Autowired
private DriverManagerDataSource dataSource;
#Autowired
private FeedItemJpaDao feedItemDao;
#Autowired
private UserJpaDao userDao;
#Before
#Transactional
public void setUp() throws Exception
{
DatabaseOperation.CLEAN_INSERT.execute(getConnection(), getDataSet());
}
#After
#Transactional
public void tearDown() throws Exception
{
DatabaseOperation.DELETE_ALL.execute(getConnection(), getDataSet());
}
#Test
#Transactional
public void testSave() throws Exception
{
User user = userDao.findById(3);
FeedItem feedItem = new FeedItem("Achievement unlocked!", user);
feedItem = feedItemDao.save(feedItem);
assertEquals(feedItem, feedItemDao.findById(feedItem.getId()));
}
private IDatabaseConnection getConnection() throws Exception
{
return new DatabaseConnection(dataSource.getConnection());
}
private IDataSet getDataSet() throws Exception
{
return new FlatXmlDataSetBuilder().build(new File("src/test/resources/dataset.xml"));
}
}
I don't understand why the error is happening -- any suggestion is appreciated!
Thank you.
EDIT: Seems like the problem is due to DbUnit: if I comment out the tearDown() method, the error doesn't occour

Answer 1

Solved the problem following this: http://tadaya.wordpress.com/2008/04/27/transaction-aware-datasource-use-dbunit-hibernate-in-spring/