Hibernate save（）和事务回滚

Question

在Hibernate中，当我save()在事务中有一个对象，然后回滚它时，保存的对象仍保留在DB中。奇怪，因为使用update()or
delete()方法不会发生此问题，而只会使用save()。

这是我正在使用的代码：

DbEntity dbEntity = getDbEntity();
HibernateUtil.beginTransaction();
Session session = HibernateUtil.getCurrentSession();
session.save(dbEntity);
HibernateUtil.rollbackTransaction();

这是 HibernateUtil 类（只是涉及的函数，我保证该getSessionFactory()方法能正常工作-
有一个Interceptor处理程序，但现在不重要了）：

private static final ThreadLocal<Session> threadSession = new ThreadLocal<Session>();
private static final ThreadLocal<Transaction> threadTransaction = new ThreadLocal<Transaction>();

/**
* Retrieves the current Session local to the thread.
* <p/>
* If no Session is open, opens a new Session for the running thread.
*
* @return Session
*/
public static Session getCurrentSession()
    throws HibernateException {
    Session s = (Session) threadSession.get();
    try {
        if (s == null) {
            log.debug("Opening new Session for this thread.");
            if (getInterceptor() != null) {
                log.debug("Using interceptor: " + getInterceptor().getClass());
                s = getSessionFactory().openSession(getInterceptor());
            } else {
                s = getSessionFactory().openSession();
            }
            threadSession.set(s);
        }
    } catch (HibernateException ex) {
        throw new HibernateException(ex);
    }
    return s;
}

/**
* Start a new database transaction.
*/
public static void beginTransaction()
    throws HibernateException {
    Transaction tx = (Transaction) threadTransaction.get();
    try {
        if (tx == null) {
            log.debug("Starting new database transaction in this thread.");
            tx = getCurrentSession().beginTransaction();
            threadTransaction.set(tx);
        }
    } catch (HibernateException ex) {
        throw new HibernateException(ex);
    }
}

/**
 * Rollback the database transaction.
 */
public static void rollbackTransaction()
    throws HibernateException {
    Transaction tx = (Transaction) threadTransaction.get();
    try {
        threadTransaction.set(null);
        if ( tx != null && !tx.wasCommitted() && !tx.wasRolledBack() ) {
            log.debug("Tyring to rollback database transaction of this thread.");
            tx.rollback();
        }
    } catch (HibernateException ex) {
        throw new HibernateException(ex);
    } finally {
        closeSession();
    }
}

谢谢

Answer 1

检查数据库是否支持回滚，即是否使用的是InnoDB表而不是MyISAM（您可以混合使用事务表和非事务表，但在大多数情况下，您希望所有表都是InnoDB）。