Erro ao tentar cadastrar um Livro

[wolleyws]

Estou finalizando o capitulo 2 e quando submeto o formulário para cadastrar recebo a seguinte exception....

HTTP Status 500 - Request processing failed; nested exception is javax.persistence.PersistenceException: org.hibernate.PersistentObjectException: detached entity passed to persist: br.com.casadocodigo.loja.models.Product

---

type Exception report

message Request processing failed; nested exception is javax.persistence.PersistenceException: org.hibernate.PersistentObjectException: detached entity passed to persist: br.com.casadocodigo.loja.models.Product

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 javax.persistence.PersistenceException: org.hibernate.PersistentObjectException: detached entity passed to persist: br.com.casadocodigo.loja.models.Product
	org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:973)
	org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:863)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
	org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:837)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)

root cause

javax.persistence.PersistenceException: org.hibernate.PersistentObjectException: detached entity passed to persist: br.com.casadocodigo.loja.models.Product
	org.hibernate.jpa.spi.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1763)
	org.hibernate.jpa.spi.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1677)
	org.hibernate.jpa.spi.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1683)
	org.hibernate.jpa.spi.AbstractEntityManagerImpl.persist(AbstractEntityManagerImpl.java:1187)
	sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	java.lang.reflect.Method.invoke(Method.java:498)
	org.springframework.orm.jpa.SharedEntityManagerCreator$SharedEntityManagerInvocationHandler.invoke(SharedEntityManagerCreator.java:289)
	com.sun.proxy.$Proxy28.persist(Unknown Source)
	br.com.casadocodigo.loja.daos.ProductDAO.save(ProductDAO.java:19)
	br.com.casadocodigo.loja.controllers.ProductsController.save(ProductsController.java:37)
	br.com.casadocodigo.loja.controllers.ProductsController$$FastClassBySpringCGLIB$$f885c078.invoke(<generated>)
	org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
	org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:717)
	org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
	org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:98)
	org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:266)
	org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:95)
	org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
	org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:653)
	br.com.casadocodigo.loja.controllers.ProductsController$$EnhancerBySpringCGLIB$$b6d56795.save(<generated>)
	sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	java.lang.reflect.Method.invoke(Method.java:498)
	org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:215)
	org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132)
	org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
	org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:781)
	org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:721)
	org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:83)
	org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:943)
	org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:877)
	org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:961)
	org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:863)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
	org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:837)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)

root cause

org.hibernate.PersistentObjectException: detached entity passed to persist: br.com.casadocodigo.loja.models.Product
	org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:139)
	org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:75)
	org.hibernate.internal.SessionImpl.firePersist(SessionImpl.java:807)
	org.hibernate.internal.SessionImpl.persist(SessionImpl.java:780)
	org.hibernate.internal.SessionImpl.persist(SessionImpl.java:785)
	org.hibernate.jpa.spi.AbstractEntityManagerImpl.persist(AbstractEntityManagerImpl.java:1181)
	sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	java.lang.reflect.Method.invoke(Method.java:498)
	org.springframework.orm.jpa.SharedEntityManagerCreator$SharedEntityManagerInvocationHandler.invoke(SharedEntityManagerCreator.java:289)
	com.sun.proxy.$Proxy28.persist(Unknown Source)
	br.com.casadocodigo.loja.daos.ProductDAO.save(ProductDAO.java:19)
	br.com.casadocodigo.loja.controllers.ProductsController.save(ProductsController.java:37)
	br.com.casadocodigo.loja.controllers.ProductsController$$FastClassBySpringCGLIB$$f885c078.invoke(<generated>)
	org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
	org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:717)
	org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
	org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:98)
	org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:266)
	org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:95)
	org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
	org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:653)
	br.com.casadocodigo.loja.controllers.ProductsController$$EnhancerBySpringCGLIB$$b6d56795.save(<generated>)
	sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	java.lang.reflect.Method.invoke(Method.java:498)
	org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:215)
	org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132)
	org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
	org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:781)
	org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:721)
	org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:83)
	org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:943)
	org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:877)
	org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:961)
	org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:863)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
	org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:837)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)

note The full stack trace of the root cause is available in the Apache Tomcat/7.0.81 logs.