How to remove duplicate objects in an ArrayList?

Hello I have an array of objects. but these objects end up repeating themselves, so I wanted a naneira to remove the duplicates.

I've tried using hasSet, but it does not seem to work with objects.

Set nova = new HashSet<>();
nova.addAll(Objetos);
Objetos.clear();
Objetos.addAll(nova);

I've tried to use a comparison if but it did not work out either.

List<T> naoDuplicado = new ArrayList<T>();
for (T obj : naoDuplicado) {
    if (!naoDuplicado.contains(Obj)) {
        naoDuplicado.add(element);
    }
}