One-root-entity-per-returned-row phenomenon of hibernate

 




public static List t() ...{


        List r = new ArrayList();


        Session s = Sf.getSession();


        Transaction tx;


        tx = s.beginTransaction();


        String sql;






        try ...{


            r = s.createCriteria(JtsUser.class)


                 .add(Restrictions.idEq(2))


                 .setFetchMode("jtsHistories", FetchMode.JOIN)


                 .setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY)


                 .list();


            tx.commit();




        } catch (Exception e) ...{


            e.printStackTrace();


            tx.rollback();




        } finally ...{


            s.close();


        }


        return r;


    }


    






    public static List tt() ...{


        List r = new ArrayList();


        Session s = Sf.getSession();


        Transaction tx;


        tx = s.beginTransaction();


        String sql;






        try ...{


            r = s.createCriteria(JtsUser.class)


                 .add(Restrictions.idEq(2))


                 .setFetchMode("jtsHistories", FetchMode.JOIN)


                 .list();


            tx.commit();




        } catch (Exception e) ...{


            e.printStackTrace();


            tx.rollback();




        } finally ...{


            s.close();


        }


        return r;


    }

t().size() is 1; While tt().size() is 4, that's the one-root-entity-per-returned-row phenomenon of hibernate.

Add "setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY)" to eliminate the one-root-entity-per-returned-row phenomenon that you're seeing.