我正在使用Struts + Hibernate，我创建了一个应用程序，我可以保存电影记录并显示它们或搜索电影。但我面临一个奇怪的问题。当我保存新的电影记录时，它会保存记录。之后我选择电影列表来显示电影表中的所有记录。它没有在第一次尝试中显示新更新的记录。当我第二次点击显示电影列表时，它肯定会显示新行。为什么hibernate不会一次性给我最近插入的行。
这是我的控制器添加电影。
public class AddMovieAction extends Action {
@Override
public ActionForward execute(ActionMapping mapping, ActionForm form, HttpServletRequest request,
HttpServletResponse response) throws Exception {
SessionFactory factory = (SessionFactory) getServlet().getServletContext().getAttribute("factory");
AddMovieForm formFilled = (AddMovieForm) form;
MoviesDaoImpl moviesDaoImpl = new MoviesDaoImpl(factory);
ActionMessages actionMessages = new ActionMessages();
if (moviesDaoImpl.addMovie(formFilled.getMovieName(), formFilled.getMovieReleaseYear(),
formFilled.getMovieLeadActor(), formFilled.getMovieHouseName())) {
actionMessages.add("success", new ActionMessage("message.success"));
}
saveMessages(request, actionMessages);
return mapping.findForward("samepage");
}
}
这是我的显示控制器
public class DisplayMoviesAction extends Action {
@Override
public ActionForward execute(ActionMapping mapping, ActionForm form, HttpServletRequest request,
HttpServletResponse response) throws Exception {
SessionFactory factory = (SessionFactory) getServlet().getServletContext().getAttribute("factory");
MoviesDaoImpl moviesDaoImpl = new MoviesDaoImpl(factory);
List<Movie> movies = moviesDaoImpl.getAllMovies();
request.setAttribute("movies", movies);
return mapping.findForward("list");
}
}
这是我的MoviesDaoImpl.java
public class MoviesDaoImpl implements MoviesDao {
private SessionFactory factory;
public MoviesDaoImpl(SessionFactory factory) {
this.factory = factory;
}
@Override
public List<Movie> getMovieByName(String name) {
Session session = factory.openSession();
session.beginTransaction();
try {
String hql = "FROM Movie M WHERE M.movieName like :movieName";
org.hibernate.Query query = session.createQuery(hql);
query.setParameter("movieName", "%" + name + "%");
@SuppressWarnings("unchecked")
List<Movie> movies = query.list();
session.getTransaction().commit();
return movies;
} catch (HibernateException e) {
e.printStackTrace();
return null;
} finally {
session.close();
}
}
@Override
public List<Movie> getAllMovies() {
Session session = factory.openSession();
session.beginTransaction();
@SuppressWarnings("unchecked")
List<Movie> movies = (List<Movie>) session.createQuery("From Movie").list();
session.getTransaction().commit();
session.close();
return movies;
}
@Override
public boolean addMovie(String movieName, String movieReleaseYear, String movieLeadActor, String movieHouse) {
Session session = factory.openSession();
try {
session.beginTransaction();
// Check if movie is already exists or not. Why create duplicate rows of same movie
Movie movie = getExistingMovieByName(movieName);
if(movie==null){
movie = new Movie();
}
movie.setMovieName(movieName);
movie.setMovieReleaseYear(movieReleaseYear);
// Check if actor already exists or not. Why create duplicate rows of same actor
Actor actor = getExistingActor(movieLeadActor);
if(actor!=null){
movie.setLeadActor(actor);
}else{
actor = new Actor();
actor.setActorName(movieLeadActor);
movie.setLeadActor(actor);
}
// Check if Movie House already exists or not. Why create duplicate rows of same Movie House
MoviesHouse moviesHouse = getMovieHouseId(movieHouse);
if (moviesHouse != null) {
System.out.println("MovieHouse Exists no need to create new record");
movie.setMovieHouse(moviesHouse);
} else {
moviesHouse = new MoviesHouse();
moviesHouse.setMovieHouseName(movieHouse);
movie.setMovieHouse(moviesHouse);
System.out.println("create movie house");
}
session.saveOrUpdate(movie);
session.saveOrUpdate(actor);
session.saveOrUpdate(moviesHouse);
session.getTransaction().commit();
} catch (HibernateException e) {
e.printStackTrace();
return false;
} finally {
session.close();
}
/*Session session1 = factory.openSession();
session1.beginTransaction();
@SuppressWarnings("unchecked")
List<Movie> movies = session1.createQuery("From Movie").list();
for(Movie m:movies){
System.out.println(m);
}
session1.getTransaction().commit();
session1.close();*/
return true;
}
public MoviesHouse getMovieHouseId(String movieHouseName) {
Session session = factory.openSession();
session.beginTransaction();
Criteria crit = session.createCriteria(MoviesHouse.class);
crit.add(Restrictions.eq("movieHouseName", movieHouseName));
@SuppressWarnings("unchecked")
List<MoviesHouse> results = crit.list();
MoviesHouse moviesHouse = null;
try {
moviesHouse = (MoviesHouse) results.get(0);
session.getTransaction().commit();
return moviesHouse;
} catch (Exception e) {
return moviesHouse;
} finally {
session.close();
}
}
public Actor getExistingActor(String actorName){
Session session = factory.openSession();
session.beginTransaction();
Criteria crit = session.createCriteria(Actor.class);
crit.add(Restrictions.eq("actorName", actorName));
@SuppressWarnings("unchecked")
List<Actor> results = crit.list();
Actor actor = null;
try {
actor = (Actor) results.get(0);
session.getTransaction().commit();
return actor;
} catch (Exception e) {
return actor;
} finally {
session.close();
}
}
public Movie getExistingMovieByName(String movieName){
Session session = factory.openSession();
session.beginTransaction();
Criteria crit = session.createCriteria(Movie.class);
crit.add(Restrictions.eq("movieName", movieName));
@SuppressWarnings("unchecked")
List<Movie> results = crit.list();
Movie movie = null;
try {
movie = (Movie) results.get(0);
session.getTransaction().commit();
return movie;
} catch (Exception e) {
return movie;
} finally {
session.close();
}
}
}
我在添加新电影后第一次调用DisplayMoviesAction。新创建的记录未获取。但是当我再次点击列表电影时，它再次调用DisplayMovieAction，这次我在列表中看到了新记录。任何人都可以帮我解决这里发生的事情吗？
答案 0 :(得分：-1)
在session.flush();
session.getTransaction().commit();