NonUniqueObjectException: A different object with the same identifier value was already associated

org.springframework.dao.DuplicateKeyException: A different object with the same identifier value was already associated with the session : [com.chuai.pojo.Department#14]; nested exception is org.hibernate.NonUniqueObjectException: A different object with the same identifier value was already associated with the session : [com.chuai.pojo.Department#14]

解决：

使用ssh框架进行update()操作的时候，出现id被占用的情况，查询资料得知是hibernate一级缓存的缘故，可在update之前，去dao层调用clera()方法清除session