Is there a way to modify the getObjects() method so it doesn't return subclasses of the class it should return?
Psychpsyo wrote ...
2016/8/23
Don't get subclasses
Psychpsyo wrote...
Is there a way to modify the getObjects() method so it doesn't return subclasses of the class it should return?
No. But if you need to do that, it might indicate a problem with your general design - perhaps you have classes extending (subclassing; inheriting from) other classes when they shouldn't.
What you can of course do is filter the list returned by getObjects(), after it is returned. That is, for each item in the list, call getClass() and check if the result is equal to the class you're looking for:
List<Apple> l = getObjects();
List<Apple> filtered = new ArrayList<Apple>();
for (Apple a : l) {
if (a.getClass() == Apple.class) {
// a is an Apple, but not a subclass of Apple
filtered.add(a);
}
}
@davmac, should not your first line read:
List<Apple> l = getObjects(Apple.class);
?
@PsychoPsyo, you might consider reviewing the first three lessons of the java tutorials on Object Oriented Programming Concepts. Those would be "What is an Object?", "...Class?" and "...Inheritance?".
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