org.hibernate.LazyInitializationException: failed to lazily initialize a collect

这个异常：org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: org.joshua.ss.entity.SysUsers.sysUsersRoleses, no session or session was closed

Exception in thread "main" org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: org.joshua.ss.entity.SysUsers.sysUsersRoleses, no session or session was closed
	at org.hibernate.collection.AbstractPersistentCollection.throwLazyInitializationException(AbstractPersistentCollection.java:380)
	at org.hibernate.collection.AbstractPersistentCollection.throwLazyInitializationExceptionIfNotConnected(AbstractPersistentCollection.java:372)
	at org.hibernate.collection.AbstractPersistentCollection.initialize(AbstractPersistentCollection.java:365)
	at org.hibernate.collection.AbstractPersistentCollection.read(AbstractPersistentCollection.java:108)
	at org.hibernate.collection.PersistentSet.iterator(PersistentSet.java:186)

原因：在hibernate的映射关系中由于延迟加载，之前的操作使session已经关闭，所以加载set属性时无可用session
解决办法：在映射文件中设置set属性 lazy='false'

<set name="sysUsersRoleses" inverse="true" cascade="all" lazy="false">
            <key>
                <column name="USER_ID" length="32" />
            </key>
            <one-to-many class="org.joshua.ss.entity.SysUsersRoles" />
        </set>