Object Relational Mapping (ORM) using NHibernate - Part 7 of 8 Completing the Ecommerce Example

using System;
using System.Collections.Generic;
using NHibernate;
using NHibernate.Criterion;

namespace ECommerceSystem.Repository
{
    public class DBRepository<T>:IRepository<T>
    {
        public DBRepository()
        {

        }
        void IRepository<T>.addItem(T item)
        {
            using (ISession session = NHibernateHelper.Create().Session)
            {
                using (ITransaction trans = session.BeginTransaction())
                {
                    session.Save(item);
                    trans.Commit();
                }
            }
        }

        void IRepository<T>.removeItem(T item)
        {
            using (ISession session = NHibernateHelper.Create().Session)
            {
                using (ITransaction trans = session.BeginTransaction())
                {
                    session.Delete(item);
                    trans.Commit();
                }
            }
        }

        void IRepository<T>.updateItem(T item)
        {
            using (ISession session = NHibernateHelper.Create().Session)
            {
                using (ITransaction trans = session.BeginTransaction())
                {
                    session.Update(item);
                    trans.Commit();
                }
            }
        }

        T IRepository<T>.getItemById(long item_id)
        {
            T temp;
            using (ISession session = NHibernateHelper.Create().Session)
            {
                temp = session.Get<T>(item_id);
            }
            return temp;
        }

        int IRepository<T>.getItemCount()
        {
            int item_count = 0;
            string type_name = typeof(T).Name;
            using (ISession session = NHibernateHelper.Create().Session)
            {
                item_count = session.CreateSQLQuery("SELECT COUNT(*) FROM "+type_name).UniqueResult<Int32>();
            }
            return item_count;
        }
    }
}