我有三个实体：
- 权限，权限， PermissionCategory
- Desc：权限可以包含许多权限，权限可以在许多权限中，permissionCategory可以包含许多权限。
1-权限＆gt; 多对多 权限
class Authority{
@ManyToMany(cascade = CascadeType.ALL)
@JoinTable(name = "authority_permission", joinColumns = { @JoinColumn(name = "authority_id", nullable = false, updatable = false) }, inverseJoinColumns = { @JoinColumn(name = "permission_id", nullable = false, updatable = false) })
private Set<Permission> permissions = new HashSet<Permission>(0);
}
2- PermissionCategory＆gt; 一对多 权限
class PermissionCategory{
@OneToMany(cascade = CascadeType.ALL, fetch = FetchType.EAGER)
@JoinTable(name = "perm_cat_map", joinColumns = { @JoinColumn(name = "perm_cat_id") }, inverseJoinColumns = { @JoinColumn(name = "permission_id") })
private Set<Permission> permissions = new HashSet<Permission>(0);
}
3-权限＆gt; 多对一 PermissionCategory
class Permission{
@ManyToOne(cascade = CascadeType.ALL)
private PermissionCategory permissionCategory;
}
案例1：添加新角色
所以我按如下方式进行：
Set<Permission> permissions=new HashSet<Permission>;
Permission permission=permissionDao.getPermissionById(1);
permissions.add(permission);
authority.setPermissions(permissions);
sessionFactory.getCurrentSession().merge(authority); // it works only with merge
这种情况很好。
案例2：删除角色
删除角色时，角色被删除，相关的角色权限，以及权限本身也被删除，我也不想删除，请告知我应该使用什么级联类型，我只想要角色和权限删除。
案例3：更新角色
所以我做了如下：
Set<Permission> permissions=new HashSet<Permission>;
Permission permission=permissionDao.getPermissionById(1);
permissions.add(permission);
authority.setPermissions(permissions);
sessionFactory.getCurrentSession().update(authority);
问题是当尝试更新上面提到的角色时，我遇到异常：
org.springframework.orm.hibernate3.HibernateSystemException: a different object with the same identifier value was already associated with the session: [com.myapp.domain.Permission#3]; nested exception is org.hibernate.NonUniqueObjectException: a different object with the same identifier value was already associated with the session: [com.myapp.domain.Permission#3]
javax.faces.FacesException: #{authority.addOrUpdateAuthority}: org.springframework.orm.hibernate3.HibernateSystemException: a different object with the same identifier value was already associated with the session: [com.myapp.domain.Permission#3]; nested exception is org.hibernate.NonUniqueObjectException: a different object with the same identifier value was already associated with the session: [com.myapp.domain.Permission#3]
at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:118)
at javax.faces.component.UICommand.broadcast(UICommand.java:315)
at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:794)
at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1259)
at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:81)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:593)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:304)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at com.ocpsoft.pretty.PrettyFilter.doFilter(PrettyFilter.java:118)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:368)
at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:99)
at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:83)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:97)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:78)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
at org.springframework.security.web.authentication.rememberme.RememberMeAuthenticationFilter.doFilter(RememberMeAuthenticationFilter.java:119)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:54)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:35)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
at org.springframework.security.web.authentication.www.BasicAuthenticationFilter.doFilter(BasicAuthenticationFilter.java:177)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:187)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:105)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:57)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:169)
at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:237)
at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:167)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:684)
at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:471)
at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:402)
at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:329)
at com.ocpsoft.pretty.PrettyFilter.doFilter(PrettyFilter.java:110)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:368)
at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:109)
at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:83)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:97)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:78)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
at org.springframework.security.web.authentication.rememberme.RememberMeAuthenticationFilter.doFilter(RememberMeAuthenticationFilter.java:119)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:54)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:35)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
at org.springframework.security.web.authentication.www.BasicAuthenticationFilter.doFilter(BasicAuthenticationFilter.java:177)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:187)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:105)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:79)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:169)
at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:237)
at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:167)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:224)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:929)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:405)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:964)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:515)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:302)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:619)
Caused by: javax.faces.el.EvaluationException: org.springframework.orm.hibernate3.HibernateSystemException: a different object with the same identifier value was already associated with the session: [com.myapp.domain.Permission#3]; nested exception is org.hibernate.NonUniqueObjectException: a different object with the same identifier value was already associated with the session: [com.myapp.domain.Permission#3]
at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:102)
at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:102)
... 87 more
Caused by: org.springframework.orm.hibernate3.HibernateSystemException: a different object with the same identifier value was already associated with the session: [com.myapp.domain.Permission#3]; nested exception is org.hibernate.NonUniqueObjectException: a different object with the same identifier value was already associated with the session: [com.myapp.domain.Permission#3]
at org.springframework.orm.hibernate3.SessionFactoryUtils.convertHibernateAccessException(SessionFactoryUtils.java:679)
at org.springframework.orm.hibernate3.HibernateTransactionManager.convertHibernateAccessException(HibernateTransactionManager.java:793)
at org.springframework.orm.hibernate3.HibernateTransactionManager.doCommit(HibernateTransactionManager.java:664)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.processCommit(AbstractPlatformTransactionManager.java:754)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:723)
at org.springframework.transaction.interceptor.TransactionAspectSupport.commitTransactionAfterReturning(TransactionAspectSupport.java:393)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:120)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202)
at $Proxy30.updateAuthority(Unknown Source)
at com.myapp.beans.AuthorityBean.addOrUpdateAuthority(AuthorityBean.java:110)
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.apache.el.parser.AstValue.invoke(AstValue.java:262)
at org.apache.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:278)
at com.sun.faces.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:105)
at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:88)
... 88 more
Caused by: org.hibernate.NonUniqueObjectException: a different object with the same identifier value was already associated with the session: [com.myapp.domain.Permission#3]
at org.hibernate.engine.StatefulPersistenceContext.checkUniqueness(StatefulPersistenceContext.java:637)
at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.performUpdate(DefaultSaveOrUpdateEventListener.java:305)
at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.entityIsDetached(DefaultSaveOrUpdateEventListener.java:246)
at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.performSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:112)
at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.onSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:93)
at org.hibernate.impl.SessionImpl.fireSaveOrUpdate(SessionImpl.java:677)
at org.hibernate.impl.SessionImpl.saveOrUpdate(SessionImpl.java:669)
at org.hibernate.engine.CascadingAction$5.cascade(CascadingAction.java:252)
at org.hibernate.engine.Cascade.cascadeToOne(Cascade.java:392)
at org.hibernate.engine.Cascade.cascadeAssociation(Cascade.java:335)
at org.hibernate.engine.Cascade.cascadeProperty(Cascade.java:204)
at org.hibernate.engine.Cascade.cascadeCollectionElements(Cascade.java:425)
at org.hibernate.engine.Cascade.cascadeCollection(Cascade.java:362)
at org.hibernate.engine.Cascade.cascadeAssociation(Cascade.java:338)
at org.hibernate.engine.Cascade.cascadeProperty(Cascade.java:204)
at org.hibernate.engine.Cascade.cascade(Cascade.java:161)
at org.hibernate.event.def.AbstractFlushingEventListener.cascadeOnFlush(AbstractFlushingEventListener.java:154)
at org.hibernate.event.def.AbstractFlushingEventListener.prepareEntityFlushes(AbstractFlushingEventListener.java:145)
at org.hibernate.event.def.AbstractFlushingEventListener.flushEverythingToExecutions(AbstractFlushingEventListener.java:88)
at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:50)
at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1206)
at org.hibernate.impl.SessionImpl.managedFlush(SessionImpl.java:375)
at org.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:137)
at org.springframework.orm.hibernate3.HibernateTransactionManager.doCommit(HibernateTransactionManager.java:656)
... 104 more
我正在使用 Hibernate 3.5.1-Final 请指教。
答案 0 :(得分：6)
在我合并然后保存或更新之后，它运作正常，如下所示：
1-保存角色:(插入新角色对象，插入连接表Authority_Permission）
authority = (Authority) getCurrentSession().merge(authority);
sessionFactory.getCurrentSession().save(authority);
2-更新角色（更新角色对象，更新连接表Authority_Permission＆gt;删除/插入）：
authority = (Authority) getCurrentSession().merge(authority);
sessionFactory.getCurrentSession().update(authority);
3-删除角色:(删除角色对象，从连接表中删除Authority_Permission）
删除cascade = CascadeType.ALL
class Authority{
@ManyToMany
@JoinTable(name = "authority_permission", joinColumns = { @JoinColumn(name = "authority_id", nullable = false, updatable = false) }, inverseJoinColumns = { @JoinColumn(name = "permission_id", nullable = false, updatable = false) })
private Set<Permission> permissions = new HashSet<Permission>(0);
仅使用：
sessionFactory.getCurrentSession().delete(authority);
但我需要一些有经验的解释，为什么我需要合并然后保存或更新，如果该解决方案是最好的，只需在博客中找到它。
答案 1 :(得分：1)
您的会话中有一个ID为3的权限，并且您尝试向会话添加具有相同ID的不同权限。 Hibernate保证在会话中永远不会有一个实体表示两次，因此抛出异常
这可能是因为您使用会话加载了一些对象（通过您的DAO）。这些附加到会话中，即它们在会话中。
您有其他来自会话外部的对象。最初可能来自不同的会话（可能是最后一个请求），尽管此会话现在可能已关闭。也许您使用new直接创建它们。罪魁祸首可能是具有引用权限的authority对象。
当您save / update authority时，{{1}}会尝试将引用的权限拖到会话中，并获得异常。
合并为您提供已在会话中的实体的对象（并根据新状态设置所有字段，可能级联到引用的对象，具体取决于配置）。因此，每个实体只有一个对象，每个人（或至少是Hibernate）都很高兴