LazyInitializationException Spring and Hibernate - spring

Question

I am getting this exception nested exception is org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: com.ibm.ro.model.Location.subLocations, could not initialize proxy - no Session.
I do get that upon accessing the collection, the transaction has already been closed that's why the code is throwing this exception. Here is my sample code
#Entity
#Table(name="location")
public class Location extends BaseEntity {
private static final long serialVersionUID = 1L;
private String name;
private List<Location> subLocations;
private Location location;
#Column(name="name")
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
#OneToMany(fetch = FetchType.LAZY, mappedBy = "location")
public List<Location> getSubLocations() {
return subLocations;
}
public void setSubLocations(List<Location> subLocations) {
this.subLocations = subLocations;
}
#ManyToOne(fetch = FetchType.LAZY)
public Location getLocation() {
return location;
}
public void setLocation(Location location) {
this.location = location;
}
#Override
public String toString() {
return "Location [name=" + name + ", subLocations=" + subLocations
+ "]";
}
}
Here is my DAO:
#Repository("locationDao")
public class LocationDao implements ILocationDao{
#Autowired
private SessionFactory sessionFactory;
#Override
public List<Location> getAll() {
Session sess = getSession();
return sess.createCriteria(Location.class).setResultTransformer(CriteriaSpecification.DISTINCT_ROOT_ENTITY).list();
}
}
Then here is my service :
#Service("locationService")
#Transactional
public class LocationService implements ILocationService{
#Autowired
ILocationDao dao;
#Override
public List<Location> getAll() {
return dao.getAll();
}
}
Here is the controller where the exception is being thrown:
#Controller
public class BaseController {
#Autowired
ILocationService service;
private static final String VIEW_INDEX = "index";
private final static org.slf4j.Logger logger = LoggerFactory.getLogger(BaseController.class);
#RequestMapping(value = "/", method = RequestMethod.GET)
public String location(ModelMap model) {
logger.debug(service.getAll().toString());
return VIEW_INDEX;
}
}
What can I do to fix the problem without using OpenSessionInViewFilter?

Answer 1

You can iterate your Location inside your service (where you still have your transaction) and call Hibernate.initialize on the elements, the force initialization of a persistent collection.
#Override
public List<Location> getAll() {
List<Location> locations = dao.getAll();
for (Location location : locations ) {
Hibernate.intialize(location.getSubLocations())
}
return locations;
}