Write operations are not allowed in read-only mode

编程技术  /  houtizong 发布于 3年前   67

错误代码:
  org.springframework.dao.InvalidDataAccessApiUsageException: Write operations are not allowed in read-only mode (FlushMode.NEVER) - turn your Session into FlushMode.AUTO or remove 'readOnly' marker from transaction definition
错误原因:
  OpenSessionInViewFilter在getSession的时候,会把获取回来的session的flush mode 设为FlushMode.NEVER。然后把该sessionFactory绑定到TransactionSynchronizationManager，使request的整个过程都使用同一个session，在请求过后再接除该sessionFactory的绑定，最后closeSessionIfNecessary根据该session是否已和transaction绑定来决定是否关闭session。在这个过程中，若HibernateTemplate 发现自当前session有不是readOnly的transaction，就会获取到FlushMode.AUTO Session，使方法拥有写权限。
也即是，如果有不是readOnly的transaction就可以由Flush.NEVER转为Flush.AUTO,拥有insert,update,delete操作权限，如果没有transaction，并且没有另外人为地设flush model的话，则doFilter的整个过程都是Flush.NEVER。所以受transaction保护的方法有写权限，没受保护的则没有。
解决办法:
  采用spring的事务声明,使方法受transaction控制

<!-- 配置事务拦截器-->     <bean id="transactionInterceptor"         class="org.springframework.transaction.interceptor.TransactionInterceptor">         <!-- 事务拦截器bean需要依赖注入一个事务管理器 -->         <property name="transactionManager" ref="transactionManager" />         <property name="transactionAttributes">             <!-- 下面定义事务传播属性-->             <props>                  <prop key="get*">PROPAGATION_REQUIRED,readOnly</prop> <prop key="find*">PROPAGATION_REQUIRED,readOnly</prop> <prop key="save*">PROPAGATION_REQUIRED</prop> <prop key="add*">PROPAGATION_REQUIRED</prop> <prop key="update*">PROPAGATION_REQUIRED</prop> <prop key="edit*">PROPAGATION_REQUIRED</prop> <prop key="delete*">PROPAGATION_REQUIRED</prop> <prop key="write">PROPAGATION_REQUIRED,readOnly</prop>            </props>         </property>     </bean> 

web.xml配置

  <filter>  <filter-name>openSessionInViewFilter</filter-name>  <!-- filter-class原来为org.springframework.orm.hibernate3.support.OpenSessionInViewFilter-->  <filter-class>com.ao.web.util.OpenSessionInViewFilter</filter-class>      <init-param>               <param-name>singleSession</param-name>            <param-value>true</param-value>         </init-param>  </filter>

com.ao.web.util.OpenSessionInViewFilter代码

package com.ao.web.util;import org.hibernate.FlushMode;import org.hibernate.Session;import org.hibernate.SessionFactory;import org.springframework.dao.DataAccessResourceFailureException;import org.springframework.orm.hibernate3.SessionFactoryUtils;/** * @author Administrator * */public class OpenSessionInViewFilter extends org.springframework.orm.hibernate3.support.OpenSessionInViewFilter {protected Session getSession(SessionFactory sessionFactory) throws DataAccessResourceFailureException {Session session = SessionFactoryUtils.getSession(sessionFactory, true);           FlushMode flushMode = session.getFlushMode();           if (flushMode != null) {           session.setFlushMode(FlushMode.AUTO);//原来为  session.setFlushMode(flushMode);        }           return session;}protected void closeSession(Session session, SessionFactory sessionFactory) {session.flush();     super.closeSession(session,sessionFactory); }}