import java.util.ArrayList; public class Test { private final ArrayList createdItems = new ArrayList<>(); private final ArrayList modifiedItems = new ArrayList<>(); private final ArrayList removedItems = new ArrayList<>(); @Override public String toString() { return getClass().getSimpleName() + " Created: " + createdItems.size() + " Modified: " + modifiedItems.size() + " Removed: " + removedItems.size(); } }