Hibernate中manytomany的问题

[www203]

做过的指点一下,没做过路过的给人人场,谢谢大家了


是权限,权限组之间的多对多的关系,我用如下方法关联(关联表是:tt_limit_to_group,里面用字段:limit_id和group_id来进行关联):

在LimitGroupPoJo类中:
@ManyToMany(cascade = { CascadeType.PERSIST, CascadeType.MERGE },
fetch = FetchType.LAZY)
@JoinTable(name="tt_limit_to_group", joinColumns={@JoinColumn(name="group_id")},
inverseJoinColumns={@JoinColumn(name="limit_id")})
public Set<LimitPoJo> getLimits() {
return limits;
}

在LimitPoJo类中:
@ManyToMany(cascade = {CascadeType.PERSIST, CascadeType.MERGE },
fetch = FetchType.LAZY, mappedBy="limits")
public Set<LimitGroupPoJo> getGroups() {
return groups;
}

如果不要这个多对多的关联的信息则tomcat启动一切正常
加了这个多对多的关系则报如下的错误
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory' defined in ServletContext resource [/WEB-INF/applicationContext.xml]: Invocation of init method failed; nested exception is org.hibernate.MappingException: Could not determine type for: java.util.Set, at table: tt_limit_group, for columns: [org.hibernate.mapping.Column(limits)]

Caused by: org.hibernate.MappingException: Could not determine type for: java.util.Set, at table: tt_limit_group, for columns: [org.hibernate.mapping.Column(limits)]

Caused by: java.lang.NoClassDefFoundError: org/apache/xerces/impl/dtd/XMLDTDDescription

[www203]

其中 org/apache/xerces/impl/dtd/XMLDTDDescription 在web-inf\lib下有xerces-2.6.2.jar的,打开rar,里面也有org/apache/xerces/impl/dtd/XMLDTDDescription的

[yibunengjing]

细看了一下，映射的很正规，没有任何问题
试着在manytomany中加入targetEntity属性试下

[xu_gdxyx]

关注中...

如下问题：

2008-4-22 17:15:49 org.apache.commons.modeler.Registry registerComponent
严重: Null component Catalina:type=JspMonitor,name=jsp,WebModule=//gcashost/host-manager,J2EEApplication=none,J2EEServer=none
2008-4-22 17:15:49 org.apache.catalina.startup.HostConfig deployDescriptor
严重: Error deploying configuration descriptor host-manager.xml
java.lang.NoClassDefFoundError: org/apache/xerces/impl/dtd/XMLDTDDescription
at org.apache.xerces.impl.dtd.XMLDTDValidator.doctypeDecl(Unknown Source)
at org.apache.xerces.impl.XMLDocumentScannerImpl.scanDoctypeDecl(Unknown Source)
at org.apache.xerces.impl.XMLDocumentScannerImpl$PrologDispatcher.dispatch(Unknown Source)
at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)
at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source)
at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source)
at org.apache.xerces.parsers.XMLParser.parse(Unknown Source)
at org.apache.xerces.parsers.AbstractSAXParser.parse(Unknown Source)
at org.apache.tomcat.util.digester.Digester.parse(Digester.java:1561)
at org.apache.catalina.startup.ContextConfig.applicationWebConfig(ContextConfig.java:350)
at org.apache.catalina.startup.ContextConfig.start(ContextConfig.java:1055)
at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:261)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4111)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:759)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:739)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:524)
at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:603)
at org.apache.catalina.startup.HostConfig.deployDescriptors(HostConfig.java:535)
at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:470)
at org.apache.catalina.startup.HostConfig.check(HostConfig.java:1181)
at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:292)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119)
at org.apache.catalina.core.ContainerBase.backgroundProcess(ContainerBase.java:1304)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1568)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1577)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.run(ContainerBase.java:1557)
at java.lang.Thread.run(Thread.java:619)