// Make sure if we are already marked complete before we start then no
// processing takes place.
boolean running = !isMarkedComplete(context);
for (int i = 0; i < listeners.length; i++) {
RepeatListener interceptor = listeners[i];
interceptor.open(context);
running = running && !isMarkedComplete(context);
if (!running)
break;
}
// Return value, default is to allow continued processing.
RepeatStatus result = RepeatStatus.CONTINUABLE;
RepeatInternalState state = createInternalState(context);
// This is the list of exceptions thrown by all active callbacks
Collection<Throwable> throwables = state.getThrowables();
// Keep a separate list of exceptions we handled that need to be
// rethrown
Collection<Throwable> deferred = new ArrayList<Throwable>();
try {
while (running) {
/*
* Run the before interceptors here, not in the task executor so
* that they all happen in the same thread - it's easier for
* tracking batch status, amongst other things.
*/
for (int i = 0; i < listeners.length; i++) {
RepeatListener interceptor = listeners[i];
interceptor.before(context);
// Allow before interceptors to veto the batch by setting
// flag.
running = running && !isMarkedComplete(context);
}
// Check that we are still running (should always be true) ...
if (running) {
try {
result = getNextResult(context, callback, state);
executeAfterInterceptors(context, result);
}
catch (Throwable throwable) {
doHandle(throwable, context, deferred);
}
// N.B. the order may be important here:
if (isComplete(context, result) || isMarkedComplete(context) || !deferred.isEmpty()) {
running = false;
}
}
}
result = result.and(waitForResults(state));
for (Throwable throwable : throwables) {
doHandle(throwable, context, deferred);
}
// Explicitly drop any references to internal state...
state = null;
}
/*
* No need for explicit catch here - if the business processing threw an
* exception it was already handled by the helper methods. An exception
* here is necessarily fatal.
*/
finally {
try {
if (!deferred.isEmpty()) {
Throwable throwable = deferred.iterator().next();
logger.debug("Handling fatal exception explicitly (rethrowing first of " + deferred.size() + "): "
+ throwable.getClass().getName() + ": " + throwable.getMessage());
rethrow(throwable);
}
}
finally {
try {
for (int i = listeners.length; i-- > 0;) {
RepeatListener interceptor = listeners[i];
interceptor.close(context);
}
}
finally {
context.close();
}