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copied!<p>In Java EE 6, you can put the <code>@Asynchronous</code> annotation on an EJB method to have the work in that method be handled by a special thread-pool:</p> <pre><code>@Stateless public class SomeBean { @Asynchronous public void doSomething() { // ... } } </code></pre> <p>Then somewhere else, inject this bean and call the <code>doSomething()</code> method. Control will return immediately.</p> <pre><code>@WebServlet("/test") public class SyncServlet extends HttpServlet { @EJB private SomeBean someBean; @Override public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { someBean.doSomething(); } } </code></pre> <p>Note that you might <strong>not</strong> need something like <code>AsyncContext asyncContext = request.startAsync()</code> here. You would use this only if the asynchronous code would still need to send something to the response.</p> <p>If you need something akin to a period timer though, and not do something in response to a request, you can use the timer service in a singleton:</p> <pre><code>@Startup @Singleton public class SomeTimerBean { @Schedule(hour = "*", minute = "*/30", second = "0", persistent = false) public void doStuff() { // ... } } </code></pre> <p>Instead of running periodically, you can also run something like this once using the <code>@TimeOut</code> annotation:</p> <pre><code>@Startup @Singleton public class SomeTimerBean { @Resource private TimerService timerService; @Postconstruct public void init() { timerService.createSingleActionTimer(0, new TimerConfig(null, false)); } @Timeout public void doStuff(Timer timer) { // ... } } </code></pre> <p>You can have variants on this, e.g. <code>SomeTimerBean</code> can also call an <code>@Asynchronous</code> method in an <em>other</em> bean as well to basically have the same effect.</p>

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