瞬態(tài)對(duì)象: 沒(méi)有進(jìn)行持久化操作的新對(duì)象.
User user=new User();
user.name="name"; //Transient 對(duì)象
持久化對(duì)象: 持久化操作過(guò)的 Transient 對(duì)象.
Persistence 對(duì)象與數(shù)據(jù)庫(kù)記錄相關(guān)聯(lián),持久化對(duì)象的屬性變化,同時(shí)數(shù)據(jù)庫(kù)中相關(guān)聯(lián)的記錄也變化.
session.save(user); //持久化操作,同時(shí)數(shù)據(jù)庫(kù)中name="name";現(xiàn)在user為Persistence 對(duì)象
user.name="name1"; //user對(duì)象屬性直接影響數(shù)據(jù)庫(kù)中記錄name="name1";
游離對(duì)象: 失去與數(shù)據(jù)庫(kù)中記錄相關(guān)聯(lián)的 Persistence 對(duì)象(主鍵已存在),或有主鍵(ID)的瞬態(tài).
new 對(duì)象====>瞬態(tài)對(duì)象==持久化操作 save() ( INSERT )==>持久對(duì)象==數(shù)據(jù)庫(kù)中記錄失去關(guān)聯(lián)( tx.commit() )==>游離對(duì)象==對(duì)象.屬性修改(UPDATE)==>持久化對(duì)象