AFAIK Object does not implement Serializable is there an object your code can implement for lock object that implements Serializable?
m- ________________________________ From: Burton Rhodes <burtonrho...@gmail.com> Sent: Monday, January 25, 2021 1:52 PM To: Struts Users Mailing List <user@struts.apache.org> Subject: Re: NPE using OpenSessionBackgroundProcess class The complete class is below (and also here: https://pastebin.com/Z8QyTRzM). It extends org.apache.struts2.interceptor.BackgroundProcess which implements serializable. Do I need to explicitly implement? Or do you see anything else that might be the cause? Many thanks. package com.afs.web.common.struts.interceptor; import com.opensymphony.xwork2.ActionInvocation; import org.apache.struts2.interceptor.BackgroundProcess; import org.springframework.orm.jpa.EntityManagerFactoryUtils; import org.springframework.orm.jpa.EntityManagerHolder; import org.springframework.transaction.support.TransactionSynchronizationManager; import javax.persistence.EntityManager; import javax.persistence.EntityManagerFactory; /** * Used in conjunction with {@link OpenSessionExecuteAndWaitInterceptor} */ public class OpenSessionBackgroundProcess extends BackgroundProcess { EntityManagerFactory entityManagerFactory; protected boolean initializationComplete; private Object lock = new Object(); // used for synchronization public OpenSessionBackgroundProcess(String name, ActionInvocation invocation, int threadPriority, EntityManagerFactory entityManagerFactory) { super(name, invocation, threadPriority); this.entityManagerFactory = entityManagerFactory; initializationComplete = true; synchronized (lock) { lock.notify(); } } protected void beforeInvocation() throws Exception { while (!initializationComplete) { try { synchronized (lock) { lock.wait(100); } } catch (InterruptedException e) { // behavior ignores cause of re-awakening. } } EntityManager em = entityManagerFactory.createEntityManager(); TransactionSynchronizationManager.bindResource(entityManagerFactory, new EntityManagerHolder(em)); super.beforeInvocation(); } protected void afterInvocation() throws Exception { super.afterInvocation(); EntityManagerHolder emHolder = (EntityManagerHolder) TransactionSynchronizationManager.unbindResource(entityManagerFactory); EntityManagerFactoryUtils.closeEntityManager(emHolder.getEntityManager()); } } On Fri, Jan 22, 2021 at 2:44 AM Lukasz Lenart <lukaszlen...@apache.org> wrote: > czw., 21 sty 2021 o 18:56 Burton Rhodes <burtonrho...@gmail.com> > napisał(a): > > synchronized (lock) { <-- **** NPE is here **** > > How is this lock defined? Is it a serializable class? > > > Regards > -- > Łukasz > + 48 606 323 122 http://www.lenart.org.pl/ > > --------------------------------------------------------------------- > To unsubscribe, e-mail: user-unsubscr...@struts.apache.org > For additional commands, e-mail: user-h...@struts.apache.org > >
