I recently needed to start a method asynchronously on the server start up.
I came up with this code (pseudocode):
@Singleton @Startup public StartupEJB { @PostConstruct private void postConstruct() { worker(); } @Asynchronous public void worker() { // Do something heavy } } |
This approach failed, the worker() method was not executed asynchronously.
I then found out that the Application Server (in my case JBoss) calls the method directly when it is located inside the same EJB: source.
The solution was to use a seperate EJB that launched the worker Thread:
@Stateless public class ExecutorBean { @Asynchronous public void execute(Runnable command) { command.run(); } } |
and
@Singleton @Startup public StartupEJB { @EJB ExecutorBean executorBean; @PostConstruct private void postConstruct() { worker(); } public void worker() { executorBean.execute(new Runnable() { @Override public void run() { // Do something heavy } }); } } |
