// prefer to use explicit configured executor on the definition
if (definition.getExecutorService() != null) {
return definition.getExecutorService();
} else if (definition.getExecutorServiceRef() != null) {
ExecutorService answer = strategy.lookup(definition, name, definition.getExecutorServiceRef());
if (answer == null) {
throw new IllegalArgumentException("ExecutorServiceRef " + definition.getExecutorServiceRef() + " not found in registry.");
}
return answer;
}