/** {@inheritDoc} */
@Override
public void addCancelRequestListener(final CancelRequestListener listener) {
Reject.ifNull(listener);
boolean invokeImmediately = false;
synchronized (stateLock) {
switch (state) {
case PENDING:
if (cancelRequestListeners == null) {
cancelRequestListeners = new LinkedList<>();
}
cancelRequestListeners.add(listener);
break;
case CANCEL_REQUESTED:
// Signal immediately outside lock.
invokeImmediately = true;
break;
case TOO_LATE:
case RESULT_SENT:
case CANCELLED:
/*
* No point in registering the callback since the request
* can never be cancelled now.
*/
break;
}
}
if (invokeImmediately) {
listener.handleCancelRequest(cancelRequestReason);
}
}
private <R extends ExtendedResult> void cancel(
final LocalizableMessage reason,
final ExtendedRequest<R> cancelRequest,
final LdapResultHandler<R> cancelResultHandler,
final boolean sendResult) {
Reject.ifNull(reason);
if (!isCancelSupported) {
if (cancelResultHandler != null) {
final Result result = Responses.newGenericExtendedResult(ResultCode.CANNOT_CANCEL);
cancelResultHandler.handleException(newLdapException(result));
}
return;
}
List<CancelRequestListener> tmpListeners = null;
boolean invokeResultHandler = false;
boolean resultHandlerIsSuccess = false;
synchronized (stateLock) {
switch (state) {
case PENDING:
/* Switch to CANCEL_REQUESTED state. */
cancelRequestReason = reason;
if (cancelResultHandler != null) {
cancelResultHandlers = new LinkedList<>();
cancelResultHandlers.add(
new ExtendedResultHandlerHolder<R>(cancelRequest, cancelResultHandler));
}
tmpListeners = cancelRequestListeners;
cancelRequestListeners = null;
state = RequestState.CANCEL_REQUESTED;
this.sendResult &= sendResult;
break;
case CANCEL_REQUESTED:
/*
* Cancel already request so listeners already invoked.
*/
if (cancelResultHandler != null) {
if (cancelResultHandlers == null) {
cancelResultHandlers = new LinkedList<>();
}
cancelResultHandlers.add(
new ExtendedResultHandlerHolder<R>(cancelRequest, cancelResultHandler));
}
break;
case TOO_LATE:
case RESULT_SENT:
/*
* Cannot cancel, so invoke result handler immediately
* outside of lock.
*/
if (cancelResultHandler != null) {
invokeResultHandler = true;
resultHandlerIsSuccess = false;
}
break;
case CANCELLED:
/*
* Multiple cancellation attempts. Clients should not do
* this, but the cancel will effectively succeed
* immediately, so invoke result handler immediately outside
* of lock.
*/
if (cancelResultHandler != null) {
invokeResultHandler = true;
resultHandlerIsSuccess = true;
}
break;
}
}
/* Invoke listeners outside of lock. */
if (tmpListeners != null) {
for (final CancelRequestListener listener : tmpListeners) {
listener.handleCancelRequest(reason);
}
}
if (invokeResultHandler) {
if (resultHandlerIsSuccess) {
final R result =
cancelRequest.getResultDecoder().newExtendedErrorResult(ResultCode.SUCCESS, "", "");
cancelResultHandler.handleResult(result);
} else {
final Result result = Responses.newGenericExtendedResult(ResultCode.TOO_LATE);
cancelResultHandler.handleException(newLdapException(result));
}
}
}
