解决org.hibernate.LazyInitializationException: could not initialize proxy

本文介绍了一种在Struts框架中遇到的懒加载异常问题及其解决方案。问题表现为Hibernate无法初始化代理对象，提示未开启Session。文章提供了两种解决方法：一是关闭懒加载，但会失去懒加载的优点；二是通过配置Spring的OpenSessionInViewFilter过滤器来解决。

问题描写叙述：

Struts Problem Report

Struts has detected an unhandled exception:

Messages:	could not initialize proxy - no Session Error reading 'name' on type future.oa.domain.Department_$$_jvstb8a_0 javax.el.ELException: Error reading 'name' on type future.oa.domain.Department_$$_jvstb8a_0
File:	org/hibernate/proxy/AbstractLazyInitializer.java

Stacktraces

org.apache.jasper.JasperException: javax.el.ELException: Error reading 'name' on type future.oa.domain.Department_$$_jvstb8a_0

    org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:549)
    org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:470)
    org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)

    .......

javax.el.ELException: Error reading 'name' on type future.oa.domain.Department_$$_jvstb8a_0

    javax.el.BeanELResolver.getValue(BeanELResolver.java:110)
    org.apache.jasper.el.JasperELResolver.getValue(JasperELResolver.java:104)
    org.apache.el.parser.AstValue.getValue(AstValue.java:183)
    org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:184)

    ......

org.hibernate.LazyInitializationException: could not initialize proxy - no Session

    org.hibernate.proxy.AbstractLazyInitializer.initialize(AbstractLazyInitializer.java:164)
    org.hibernate.proxy.AbstractLazyInitializer.getImplementation(AbstractLazyInitializer.java:285)
    org.hibernate.proxy.pojo.javassist.JavassistLazyInitializer.invoke(JavassistLazyInitializer.java:185)
    future.oa.domain.Department_$$_jvstb8a_0.getName(Department_$$_jvstb8a_0.java)
    sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

    ......

You are seeing this page because development mode is enabled. Development mode, or devMode, enables extra debugging behaviors and reports to assist developers. To disable this mode, set:

  struts.devMode=false

in your WEB-INF/classes/struts.properties file.

解决方法：

解决懒载入问题。

方法一:（直接将懒载入关闭）：

在 .hbm.xml 里

缺点：一些懒载入的长处也用不了了。

方法二:

在 web.xml里（注：要在  之前）

<filter>
<filter-name>OpenSessionInViewFilter</filter-name>
<filter-class>org.springframework.orm.hibernate3.support.OpenSessionInViewFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>OpenSessionInViewFilter</filter-name>
<url-pattern>*.action</url-pattern>
</filter-mapping>

然后在 *.hbm.xml里再打开懒载入。