open session in view 的用法

第一种方式：Filter过滤器实现
<filter>
    <filter-name>openSessionInView</filter-name>
    <filter-class>org.springframework.orm.hibernate3.support.OpenSessionInViewFilter</filter-class>
</filter>
         <filter-mapping>
             <filter-name>openSessionInView</filter-name>
   <url-pattern>/*</url-pattern>
</filter-mapping>



第二种方式：在appliactionContext.xml中配置 不推荐

<!-- =========== OpenSession In View pattern ==============-->
    <bean id="openSessionInViewInterceptor"
          class="org.springframework.orm.hibernate3.support.OpenSessionInViewInterceptor">
        <property name="sessionFactory" ref="sessionFactory"/>
    </bean>

    <bean id="urlMapping" class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping">
        <property name="interceptors" ref="openSessionInViewInterceptor"/>
        <property name="mappings">
            <props>
            ......
            </props>
        </property>
    </bean>


=====Spring+Hibernate中，  集合映射如果使用lazy="true"， 当PO传到View层时， 出现未初始化session已关闭的错误，只能在dao先初始化 。所以此时就要用到
open sessin in view 过滤器了