4 Replies Latest reply: Apr 17, 2012 3:43 AM by Ivo Maixner RSS

    Solder exceptions: support handling unexpected exceptions

    Ivo Maixner Newbie

      Should there be a way to handle exceptions not handled by any other handler?


      public class ExceptionHandler {
           public void unexpectedException(@Handles CaughtException<Throwable> event) {
                if (!event.isMarkedHandled()) {
                     log.error("Unexpected exception", event.getException());
                     messages.error(new BundleKey(MESSAGE_BUNDLE, "unexpected.exception"));
            ... other, specific handlers... like e.g.:
           public void optimisticLockException(
                     @Handles CaughtException<OptimisticLockException> event) {
                messages.error(new BundleKey(MESSAGE_BUNDLE, "optimistic.lock.exception"));


      This code above in the unexpectedException() however gets in the way when a specific handler wants to respond to a non-root cause exception, which is the case with OptimisticLockException, which wraps a root cause Hibernate exception. During the DEPTH_FIRST traversal, Solder first resolves the root cause Hibernate exception up its class hierarchy to Throwable and so the unexpectedException() handler gets invoked before the optimisticLockException() handler gets a chance to handle the event.


      Some ideas:

      • an UnhandledException event fired from ExceptionHandlerDispatch.executeHandlers as a last chance to handle it before re-throwing it as unhandled
      • a third traversal type - after BREADTH_FIRST and DEPTH_FIRST