Collections.emptyList() instead of null check?

Question

If I have a rarely used collection in some class which may be instantiated many times, I may sometimes resort to the following \"idiom\" in order to save unnecessary object crea

Answer 1

Here's a variation on using optional as @Stas suggested, but also using the isEmpty immutable collection as originally requested in the question:

public static List addElement(List list, String toAdd) {
   List newList = Optional.ofNullable(list).orElse(Collections.emptyList());
   newList.add(toAdd);
   return newList;
}

This approach is also the closest thing I can find to the nice ability in Javascript to use an empty array if the collection is null.

For example:

// no need to indent everything inside a null check of myObjects
for (MyObj myObj : Optional.ofNullable(myObjects).orElse(Collections.emptyList())){
    // do stuff with myObj
}