HTTP Status 500 - 

--------------------------------------------------------------------------------

type Exception report

message 

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

exception 

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.hibernate.AssertionFailure: null id in com.lzw.model.TbMember entry (don't flush the Session after an exception occurs)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:408)
org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:360)
javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)


root cause 

org.hibernate.AssertionFailure: null id in com.lzw.model.TbMember entry (don't flush the Session after an exception occurs)
org.hibernate.event.def.DefaultFlushEntityEventListener.checkId(DefaultFlushEntityEventListener.java:55)
org.hibernate.event.def.DefaultFlushEntityEventListener.getValues(DefaultFlushEntityEventListener.java:164)
org.hibernate.event.def.DefaultFlushEntityEventListener.onFlushEntity(DefaultFlushEntityEventListener.java:120)
org.hibernate.event.def.AbstractFlushingEventListener.flushEntities(AbstractFlushingEventListener.java:196)
org.hibernate.event.def.AbstractFlushingEventListener.flushEverythingToExecutions(AbstractFlushingEventListener.java:76)
org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:26)
org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1000)
org.hibernate.impl.SessionImpl.managedFlush(SessionImpl.java:338)
org.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:106)
org.springframework.orm.hibernate3.HibernateTransactionManager.doCommit(HibernateTransactionManager.java:561)
org.springframework.transaction.support.AbstractPlatformTransactionManager.processCommit(AbstractPlatformTransactionManager.java:611)
org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:581)
org.springframework.transaction.interceptor.TransactionAspectSupport.commitTransactionAfterReturning(TransactionAspectSupport.java:307)
org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:117)
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:176)
org.springframework.aop.framework.Cglib2AopProxy$DynamicAdvisedInterceptor.intercept(Cglib2AopProxy.java:615)
com.lzw.dao.Dao$$EnhancerByCGLIB$$cd4b3071.insertObject(<generated>)
com.lzw.RegisterController.onSubmit(RegisterController.java:32)
org.springframework.web.servlet.mvc.SimpleFormController.onSubmit(SimpleFormController.java:380)
org.springframework.web.servlet.mvc.SimpleFormController.processFormSubmission(SimpleFormController.java:267)
org.springframework.web.servlet.mvc.AbstractFormController.handleRequestInternal(AbstractFormController.java:250)
com.lzw.RegisterController.handleRequestInternal(RegisterController.java:38)
org.springframework.web.servlet.mvc.AbstractController.handleRequest(AbstractController.java:153)
org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter.handle(SimpleControllerHandlerAdapter.java:45)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:820)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:755)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:396)
org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:360)
javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)