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java - Return empty Vector collection instead of null

I have a function that returns a Vector and in case of an error, I want to return an empty Vector which can be checked using Collections.isEmpty by the calling method. But I am unable to find the way to do it as Collections provides Collections.emptyList functions for List, Maps, etc. but not for Vector and I am forced to return null by function which I want to avoid.

How to achieve this?

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You could return a new Vector<X>(), but a better solution would be to move away from Vector which has been obsolete for (many) years. Unless you require concurrency features, you can use an ArrayList instead.

You added that you receive the Vector from a third party service. Don't forget that a Vector is a List, so you could maybe use something like this:

public List<X> getData() {
  try {
    Vector<X> v = getDataFromService();
    return v;
  } catch (ServiceException e) {
    return Collections.emptyList();
  }
}

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