java 使用@ElementCollection 映射 Set<enum>
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Mapping Set<enum> using @ElementCollection
提问by MoienGK
I have the following enum:
我有以下枚举：
package ir.raysis.tcs.rule.days;
public enum Days {
SUNDAY, MONDAY, TUESDAY, WEDNESDAY,
THURSDAY, FRIDAY, SATURDAY;
}
I tried to map it as a Set<Days>days as follows:
我尝试将其映射Set<Days>为如下日期：
@ElementCollection(targetClass = Days.class)
@JoinTable(name = "days",joinColumns = @JoinColumn(name = "rule_id"))
@Column(name ="daysOfWeek", nullable = false) @Enumerated(EnumType.STRING)
private Set<Days> days = new HashSet<>();
However, it throws the following exception:
但是，它会引发以下异常：
Initial SessionFactory creation failed.org.hibernate.MappingException: Could not determine type for: java.util.Set, at table: rule, for columns: [org.hibernate.mapping.Column(days)]
Apr 14, 2013 4:15:17 PM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [jsp] in context with path [/ptcs] threw exception [javax.servlet.ServletException: java.lang.ExceptionInInitializerError] with root cause
org.hibernate.MappingException: Could not determine type for: java.util.Set, at table: rule, for columns: [org.hibernate.mapping.Column(days)]
at org.hibernate.mapping.SimpleValue.getType(SimpleValue.java:306)
at org.hibernate.mapping.SimpleValue.isValid(SimpleValue.java:290)
at org.hibernate.mapping.Property.isValid(Property.java:217)
at org.hibernate.mapping.PersistentClass.validate(PersistentClass.java:464)
at org.hibernate.mapping.RootClass.validate(RootClass.java:235)
at org.hibernate.cfg.Configuration.validate(Configuration.java:1362)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1865)
at ir.raysis.tcs.db.HibernateUtil.<clinit>(HibernateUtil.java:18)
at ir.raysis.tcs.db.SaveUpadteDelete.save(SaveUpadteDelete.java:33)
at ir.raysis.tcs.db.dBAllFunc.save(dBAllFunc.java:35)
at ir.raysis.tcs.db.AbsDBObject.save(AbsDBObject.java:45)
at ir.raysis.tcs.action.CreateMemberAction.execute(CreateMemberAction.java:31)
at org.apache.jsp.action.createMember_jsp._jspService(createMember_jsp.java:79)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:432)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:225)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
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:98)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1001)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:579)
at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:1770)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
How do I properly map it?
我如何正确映射它？
回答by MoienGK
for future googlers! finally i managed to solve the problem, i just had to put the annotations somewhere else in my code ,
为了未来的谷歌人！最后我设法解决了这个问题，我只需要将注释放在我的代码中的其他地方，
@ElementCollection(targetClass = Days.class)
@CollectionTable(name = "days", joinColumns = @JoinColumn(name = "rule_id"))
@Column(name = "daysOfWeek", nullable = false)
@Enumerated(EnumType.STRING)
public Set<Days> getDays() {
return days;
}
as you can see i wrote the annotation code above and before the getter method(instead of placing it before the attribute declaration code) and problem solved, anyone who can explain me what causes this will be appreciated. thank you
正如您所看到的，我在上面和 getter 方法之前（而不是将它放在属性声明代码之前）编写了注释代码，问题解决了，任何能解释这是什么原因的人都将不胜感激。谢谢
回答by Pace
Try using @CollectionTableand not @JoinTable
尝试使用@CollectionTable而不是@JoinTable
