http://uule.iteye.com/blog/1445678
悲观锁乐观锁
http://blog.csdn.net/hongchangfirst/article/details/26004335
http://www.cnblogs.com/chenlulouis/archive/2010/07/07/1772631.html
spring事物隔离级别和
事务的隔离级别
原文：http://www.cnblogs.com/sj521/p/5892734.html
