hibernate proxy异常

码拜

10年 ago

hibernate 背景：最近搭建struts2,spring4,hibernate 4 的框架。问题：查询用户fetch=join部门不报错，使用代理延迟加载就报错（我做登陆校验用户密码时，不需要加载部门）。配置： @Entity @Table(name = "T_USER") public class User { .... .... @ManyToOne @LazyToOne(LazyToOneOption.RROXY) public Department getDept() { return dept; } public void setDept(Department dept) { this.dept = dept; } } 异常： Caused by: java.lang.ClassCastException: com.jst.myjstBase.model.Department_$$_javassist_0 cannot be cast to javassist.util.proxy.Proxy at org.hibernate.proxy.pojo.javassist.JavassistLazyInitializer.getProxy(JavassistLazyInitializer.java:147) at org.hibernate.proxy.pojo.javassist.JavassistProxyFactory.getProxy(JavassistProxyFactory.java:75) at org.hibernate.tuple.entity.AbstractEntityTuplizer.createProxy(AbstractEntityTuplizer.java:771) at org.hibernate.persister.entity.AbstractEntityPersister.createProxy(AbstractEntityPersister.java:4613) at org.hibernate.event.internal.DefaultLoadEventListener.createProxyIfNecessary(DefaultLoadEventListener.java:349) at org.hibernate.event.internal.DefaultLoadEventListener.proxyOrLoad(DefaultLoadEventListener.java:270) at org.hibernate.event.internal.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:150) at org.hibernate.internal.SessionImpl.fireLoad(SessionImpl.java:1070) at org.hibernate.internal.SessionImpl.internalLoad(SessionImpl.java:989) at org.hibernate.type.EntityType.resolveIdentifier(EntityType.java:716) at org.hibernate.type.EntityType.resolve(EntityType.java:502) at org.hibernate.engine.internal.TwoPhaseLoad.doInitializeEntity(TwoPhaseLoad.java:170) at org.hibernate.engine.internal.TwoPhaseLoad.initializeEntity(TwoPhaseLoad.java:144) at org.hibernate.loader.Loader.initializeEntitiesAndCollections(Loader.java:1114) at org.hibernate.loader.Loader.processResultSet(Loader.java:972) at org.hibernate.loader.Loader.doQuery(Loader.java:920) at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:354) at org.hibernate.loader.Loader.doList(Loader.java:2553) at org.hibernate.loader.Loader.doList(Loader.java:2539) at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2369) at org.hibernate.loader.Loader.list(Loader.java:2364) at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:496) at org.hibernate.hql.internal.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:387) at org.hibernate.engine.query.spi.HQLQueryPlan.performList(HQLQueryPlan.java:231) at org.hibernate.internal.SessionImpl.list(SessionImpl.java:1264) at org.hibernate.internal.QueryImpl.list(QueryImpl.java:103) at com.jst.myjstBase.DAO.impl.UserDAOImpl.findUserByLoginName(UserDAOImpl.java:24) at com.jst.myjstBase.service.impl.UserServiceImpl.findUserByLoginName(UserServiceImpl.java:22) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:317) at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:190) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157) at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:98) at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:262) at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:95) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:207) at $Proxy20.findUserByLoginName(Unknown Source) at com.jst.common.service.impl.ShiroDbRealm.doGetAuthenticationInfo(ShiroDbRealm.java:54) at org.apache.shiro.realm.AuthenticatingRealm.getAuthenticationInfo(AuthenticatingRealm.java:568) at org.apache.shiro.authc.pam.ModularRealmAuthenticator.doSingleRealmAuthentication(ModularRealmAuthenticator.java:180) at org.apache.shiro.authc.pam.ModularRealmAuthenticator.doAuthenticate(ModularRealmAuthenticator.java:267) at org.apache.shiro.authc.AbstractAuthenticator.authenticate(AbstractAuthenticator.java:198) ... 95 more
50分	类匹配错误，是不是代理找错类了
	去掉@LazyToOne(LazyToOneOption.PROXY)可以运行，但会把部门的信息left out join出来。
50分	用的都是什么包看下，应该存在多个包都包含注解类LazyToOne，最后转型错误。使用hibernate4自带的required里的lib即可。
	可以用 @ManyToOne(fetch=FetchType.EAGER) @JoinColumn(name="dept_id") public Department getDept() { return dept; } 不可以用，报错 @ManyToOne(fetch=FetchType.LAZY) @JoinColumn(name="dept_id") public Department getDept() { return dept; }
	引用 4 楼 javaee_ssh 的回复: 可以用 @ManyToOne(fetch=FetchType.EAGER) @JoinColumn(name="dept_id") public Department getDept() { return dept; } 不可以用，报错 @ManyToOne(fetch=FetchType.LAZY) @JoinColumn(name="dept_id") public Department getDept() { return dept; } 我记得以前报过这个错，是因为spring事务配置的问题
	弄了两个javassist.jar真是惭愧，删除了低版本的，系统正常，谢谢大家，散分。