我正在尝试向我的论坛添加主题，每次创建论坛对象时都会收到此错误：
HTTP Status 500 -
type Exception report
message
description The server encountered an internal error () that prevented it from fulfilling this request.
exception
org.hibernate.AssertionFailure: null id in com.versusfootball.hibernate.entity.ForumTopic entry (don't flush the Session after an exception occurs)
org.hibernate.event.def.DefaultFlushEntityEventListener.checkId(DefaultFlushEntityEventListener.java:82)
org.hibernate.event.def.DefaultFlushEntityEventListener.getValues(DefaultFlushEntityEventListener.java:190)
org.hibernate.event.def.DefaultFlushEntityEventListener.onFlushEntity(DefaultFlushEntityEventListener.java:147)
org.hibernate.event.def.AbstractFlushingEventListener.flushEntities(AbstractFlushingEventListener.java:219)
org.hibernate.event.def.AbstractFlushingEventListener.flushEverythingToExecutions(AbstractFlushingEventListener.java:99)
org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:50)
org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1216)
com.versusfootball.dao.DAO.rollback(DAO.java:46)
com.versusfootball.dao.ForumTopicDAO.create(ForumTopicDAO.java:31)
com.versusfootball.struts.main.forum.SaveForumSubject.execute(SaveForumSubject.java:46)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
java.lang.reflect.Method.invoke(Method.java:616)
com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:452)
com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:291)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:254)
com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:176)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:263)
org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:68)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:133)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:207)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:207)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:190)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:75)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:94)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:243)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:100)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:141)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:267)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:142)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:166)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:176)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:190)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:187)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:52)
org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:485)
org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:395)
com.versusfootball.filters.InitSession.doFilter(InitSession.java:81)
com.versusfootball.filters.DisableUrlSessionFilter.doFilter(DisableUrlSessionFilter.java:87)
note The full stack trace of the root cause is available in the Apache Tomcat/6.0.29 logs.
Apache Tomcat/6.0.29
这是我的论坛构造函数：
public Forum create (Forum forum) throws AppException {
try {
begin();
if(forum.getId() != null) {
getSession().merge(forum);
}
else {
getSession().save(forum);
}
commit();
close();
return forum;
}
catch (HibernateException e) {
log.error("Error creating forum : " + e.getCause().getMessage());
rollback();
throw new AppException(e.getCause().getMessage());
}
}
这是我的提交执行：
package com.versusfootball.struts.main.forum;
import java.util.Date;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import org.apache.log4j.Logger;
import org.apache.struts2.interceptor.ServletRequestAware;
import com.opensymphony.xwork2.ActionSupport;
import com.versusfootball.dao.ForumDAO;
import com.versusfootball.dao.ForumMessageDAO;
import com.versusfootball.dao.ForumTopicDAO;
import com.versusfootball.exceptions.AppException;
import com.versusfootball.hibernate.entity.Forum;
import com.versusfootball.hibernate.entity.ForumMessage;
import com.versusfootball.hibernate.entity.ForumTopic;
import com.versusfootball.hibernate.entity.Personne;
public class SaveForumSubject extends ActionSupport implements ServletRequestAware {
/**
*
*/
private static final long serialVersionUID = -2131201082127318301L;
private static final Logger log = Logger.getLogger(SaveForumSubject.class);
public String execute() {
try {
HttpSession session = request.getSession();
Personne usager = (Personne)session.getAttribute("usagerFoot");
if(usager == null) {
return ERROR;
}
Date today = new Date();
forum = forumDAO.getById(forumId);
ForumTopic newTopic = new ForumTopic();
newTopic.setNbMessages(0);
newTopic.setNbViews(0);
newTopic.setForum(forum);
newTopic.setCreationDate(today);
newTopic.setTitle(msgTitle);
newTopic.setAuthor(usager);
newTopic = ftDAO.create(newTopic);
subjectId = newTopic.getId();
ForumMessage newMsg = new ForumMessage();
newMsg.setAuthor(usager);
newMsg.setMessageDate(today);
message = message.replaceAll("\n", "<br />");
newMsg.setText(message);
newMsg.setTopic(newTopic);
newMsg.setNiveau(0);
newMsg = fmDAO.create(newMsg);
messageId = newMsg.getId();
forum.setNbMessages(forum.getNbMessages() + 1);
forum.setNbTopics(forum.getNbTopics() + 1);
forum.setLastMessage(newMsg);
newTopic.setLastMessage(newMsg);
newTopic = ftDAO.create(newTopic);
forumDAO.create(forum);
} catch (AppException e) {
// TODO Auto-generated catch block
log.error(e.getMessage());
}
return SUCCESS;
}
private ForumDAO forumDAO = new ForumDAO();
private ForumMessageDAO fmDAO = new ForumMessageDAO();
private ForumTopicDAO ftDAO = new ForumTopicDAO();
private HttpServletRequest request;
private String msgTitle = "";
private String message = "";
private Integer forumId;
private Integer messageId;
private Integer subjectId;
private Forum forum;
public void setMsgTitle(String msgTitle) {
this.msgTitle = msgTitle;
}
public String getMsgTitle() {
return msgTitle;
}
public void setMessage(String message) {
this.message = message;
}
public String getMessage() {
return message;
}
public void setForumId(Integer forumId) {
this.forumId = forumId;
}
public Integer getForumId() {
return forumId;
}
public Integer getMessageId() {
return messageId;
}
public Forum getForum() {
return forum;
}
public Integer getSubjectId() {
return subjectId;
}
@Override
public void setServletRequest(HttpServletRequest request) {
this.request = request;
}
}
有人知道我该如何解决这个问题吗？