1、org.hibernate.LazyInitializationException: could not initialize proxy - the owning Session was closed.
問(wèn)題:hibernate3默認(rèn)的lazy為true,使用代理模式proxy屬性允許延遲加載類的持久化實(shí)例。調(diào)用session.load()方法,Hibernate開(kāi)始會(huì)返回CGLIB代理,除主鍵外的其他值均為null。當(dāng)代理的某個(gè)方法被實(shí)際調(diào)用的時(shí)候, 真實(shí)的持久化對(duì)象才會(huì)被裝載,但必須在同一個(gè)session中。如session.close()前一直未調(diào)用方法,close()后再調(diào)用,報(bào)上述錯(cuò)誤。
解決:a.hbm.xml中 class項(xiàng),加上lazy=false
??????????? b.使用session.get()方法,將不延遲,直接取出對(duì)象實(shí)例。
2、java.sql.SQLException: [Microsoft][SQLServer 2000 Driver for JDBC]Can't start a cloned connection while in manual transaction mode.
問(wèn)題:MS SQLServer在設(shè)置為autoCommit=false,SelectMethod=direct(SelectMethod如果不設(shè)置,默認(rèn)為direct)時(shí),處理多個(gè)statement將報(bào)以上錯(cuò)誤
解決:在url加上設(shè)置SelectMethod=Cursor
3、java.lang.NullPointerException: Problem with checked-in Statement, discarding.
問(wèn)題:oracle9i前的jdbc Driver有bug,多個(gè)statement亦會(huì)出錯(cuò)
解決:在http://www.oracle.com/technology/software/tech/java/sqlj_jdbc/index.html上下載最新的ojdbc14.jar,版本為10.2.0.1.0