问题
I seem to be randomly getting the following LazyInitializationException in a Spring/MVC 3.0/Hibernate 3.5 application in spite of seeing the filter in the stack trace itself. Any idea on what I should look into?
07 Jun 2011 13:48:47,152 [ERROR] (http-3443-2) org.hibernate.LazyInitializationException: could not initialize proxy - no Session
org.hibernate.LazyInitializationException: could not initialize proxy - no Session
at org.hibernate.proxy.AbstractLazyInitializer.initialize(AbstractLazyInitializer.java:86)
at org.hibernate.proxy.AbstractLazyInitializer.getImplementation(AbstractLazyInitializer.java:140)
at org.hibernate.proxy.pojo.javassist.JavassistLazyInitializer.invoke(JavassistLazyInitializer.java:190)
at com.test.Image_$$_javassist_18.getMyKey(Image_$$_javassist_18.java)
at com.test.AppTagHelper.getAssetUrl(AppTagHelper.java:66)
at sun.reflect.GeneratedMethodAccessor81.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.el.parser.AstFunction.getValue(AstFunction.java:110)
at org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:186)
at org.apache.jasper.runtime.PageContextImpl.proprietaryEvaluate(PageContextImpl.java:935)
at org.apache.jsp.WEB_002dINF.view.home_jsp._jspx_meth_c_005fout_005f2(home_jsp.java:1027)
at org.apache.jsp.WEB_002dINF.view.home_jsp._jspx_meth_c_005fwhen_005f1(home_jsp.java:1002)
at org.apache.jsp.WEB_002dINF.view.home_jsp._jspx_meth_c_005fchoose_005f1(home_jsp.java:969)
at org.apache.jsp.WEB_002dINF.view.home_jsp._jspx_meth_display_005fcolumn_005f0(home_jsp.java:867)
at org.apache.jsp.WEB_002dINF.view.home_jsp._jspService(home_jsp.java:214)
<<VARIOUS SPRING FILTERS>>
at org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198)
From the web.xml:
<filter>
<filter-name>hibernateFilter</filter-name>
<filter-class>
org.springframework.orm.hibernate3.support.OpenSessionInViewFilter</filter-class>
<init-param>
<param-name>sessionFactoryBeanName</param-name>
<param-value>sessionFactory</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>hibernateFilter</filter-name>
<url-pattern>*.html</url-pattern>
</filter-mapping>
<filter-mapping>
<filter-name>hibernateFilter</filter-name>
<url-pattern>*.json</url-pattern>
</filter-mapping>
Update, adding definition of SessionFactoryBean:
<bean id="sessionFactory" class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean" depends-on="dataSource">
<property name="dataSource" ref="dataSource" />
<property name="packagesToScan" value="com.test.model" />
<property name="schemaUpdate" value="false" />
<property name="eventListeners">
<map>
<!-- Create -->
<entry key="pre-insert">
<ref local="hibernateCreateListener"/>
</entry>
<entry key="post-insert">
<ref local="hibernateRevisionListener"/>
</entry>
<!-- Update -->
<entry key="pre-update">
<ref local="hibernateUpdateListener"/>
</entry>
<entry key="post-update">
<ref local="hibernateRevisionListener"/>
</entry>
<entry key="post-delete">
<ref local="hibernateRevisionListener"/>
</entry>
<entry key="pre-collection-update">
<ref local="hibernateRevisionListener"/>
</entry>
<entry key="post-collection-recreate">
<ref local="hibernateRevisionListener"/>
</entry>
<entry key="pre-collection-remove">
<ref local="hibernateRevisionListener"/>
</entry>
</map>
</property>
<property name="entityInterceptor">
<ref bean="hibernateAuditInterceptor"/>
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">org.hibernate.dialect.Oracle10gDialect</prop>
<prop key="hibernate.default_schema">${app.databaseSchema}</prop>
<prop key="hibernate.show_sql">false</prop>
<prop key="hibernate.format_sql">false</prop>
<prop key="hibernate.use_sql_comments">false</prop>
<prop key="hibernate.connection.oracle.jdbc.ReadTimeout">60000</prop>
<prop key="org.hibernate.envers.revisionTypeFieldName">REV_TYPE</prop>
<prop key="org.hibernate.envers.revisionFieldName">REV_ID</prop>
</props>
</property>
</bean>
回答1:
Two most common causes I know of for lazy load exceptions with the filter on are either trying to access something after an exception has invalidated the Hibernate Session, or trying to access a field on something that was actually sitting around on the Web session and isn't attached.
public interface EntityService {
@Transactional
EntityA getA(Long id);
@Transactional
EntityB getB(Long id);
}
public class WebPageController {
public void handleGet(Long id1, Long id2) {
EntityA a = entityService.getA(id1);
try {
EntityB b = entityService.getB(id2);
} catch (Exception e) {
//print somthething
}
a.accessLazyField(); //will throw lazy load after getB throws exception
}
}
Obviously lots of code and annotations ommitted for clarity :)
@SessionAttributes("model")
public class WebPageController {
@ModelAttribute("model")
@RequestMapping(method=RequestMethod.GET)
public EntityA handleGet(Long id) {
return entityService.getA(id);
}
@RequestMapping(method=RequestMethod.POST)
public String handlePost(@ModelAttribute("model") EntityA a) {
a.accessLazyField(); //will throw lazy load if the field was not accessed during original page rendering
return "viewName";
}
}
回答2:
In spring MVC You should use OpenSessionInViewInterceptor instead of filter In my current project this is configured that way:
<mvc:annotation-driven/>
<mvc:interceptors>
<bean class="org.springframework.orm.hibernate3.support.OpenSessionInViewInterceptor">
<property name="sessionFactory">
<ref local="sessionFactory"/>
</property>
</bean>
</mvc:interceptors>
Where sessionFactory refers to org.springframework.orm.hibernate3.LocalSessionFactoryBean
Works flawless.
来源：https://stackoverflow.com/questions/6268627/lazyinitializationexception-in-spite-of-opensessioninviewfilter