Getting the following Exception sometimes in a random manner while performing the session.lock

Kindly help. This stopping us fromgoing to production.

HTTP Status 500 -

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type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

javax.servlet.ServletException: Illegal attempt to associate a collection with two open sessions
org.apache.struts.action.RequestProcessor.processException(RequestProcessor.java:516)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:423)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:226)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1164)
org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:415)
javax.servlet.http.HttpServlet.service(HttpServlet.java:763)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)


root cause

net.sf.hibernate.HibernateException: Illegal attempt to associate a collection with two open sessions
net.sf.hibernate.collection.PersistentCollection.setCurrentSession(PersistentCollection.java:257)
net.sf.hibernate.impl.OnLockVisitor.processCollection(OnLockVisitor.java:41)
net.sf.hibernate.impl.AbstractVisitor.processValue(AbstractVisitor.java:69)
net.sf.hibernate.impl.AbstractVisitor.processValues(AbstractVisitor.java:36)
net.sf.hibernate.impl.AbstractVisitor.process(AbstractVisitor.java:91)
net.sf.hibernate.impl.SessionImpl.reassociate(SessionImpl.java:1698)
net.sf.hibernate.impl.SessionImpl.lock(SessionImpl.java:1718)
com.acs.onboarding.candidate.CandidateSaveAction.saveCommonDataDetails(CandidateSaveAction.java:100)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
java.lang.reflect.Method.invoke(Method.java:324)
org.apache.struts.actions.DispatchAction.dispatchMethod(DispatchAction.java:276)
org.apache.struts.actions.DispatchAction.execute(DispatchAction.java:196)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:421)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:226)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1164)
org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:415)
javax.servlet.http.HttpServlet.service(HttpServlet.java:763)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)


note The full stack trace of the root cause is available in the Tomcat logs.


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Apache Tomcat/5.0.18