我有一个无状态 bean 来管理我的计时器服务:
@Stateless
@Depends("jboss.ha:service=HASingletonDeployer,type=Barrier")
public class TimerManagerBean implements ITimerManagerLocal {
private static final Logger log = Logger.getLogger(TimerManagerBean.class);
private @Resource
SessionContext ctx;
private @EJB ISomeEjbLocal someEjb;
public void scheduleTimer(long initialDuration, long intervalDuration, Serializable info) {
if (info.equals(ITimerManagerLocal.TIMER_ID_1)) {
ctx.getTimerService().createTimer(initialDuration, intervalDuration, info);
}
}
@Override
public void cancelTimer(Serializable info) {
final Collection<Timer> timers = ctx.getTimerService().getTimers();
for (final Timer timer : timers) {
if (timer.getInfo().equals(info)) {
log.info("Timer[info=" + info + "] found, cancelling...");
timer.cancel();
log.info("Timer[info=" + info + "] cancelled");
}
}
}
@Override
@Timeout
public void timeoutHandler(Timer timer) throws Exception {
Serializable info = timer.getInfo();
if (ITimerManagerLocal.TIMER_ID_1.equals(info)) {
someEjb.doSomething(); // what happen if this throw exception?
}
}
}
}
这是我的本地接口:
@Local
public interface ITimerManagerLocal {
public static final String TIMER_ID_1 = "TIMER_ID_1";
public void scheduleTimer(long initialDuration, long intervalDuration, Serializable info);
public void cancelTimer(Serializable info);
public void timeoutHandler(Timer timer) throws Exception;
}
我用它来创建/取消/安排计时器。该服务过去几个月都可以正常工作,但现在它开始将空计时器对象传递给 timeoutHandler 方法,这会引发 NullPointerException。这发生在每次调用 timeoutHandler 方法时。我正在使用 postgres 来存储计时器信息,而不是 hsdb。我认为这在迁移到 postgres 9 后开始发生,但我不明白为什么并且可能是我错了。另外,当 timer.getInfo() 抛出 NullPointerException 时 timeoutHandler 方法会发生什么(因为 timer 为空)。这个异常在哪里抛出?它会阻止正确重新安排计时器吗?
谢谢。