LinkedHashSet - insertion order and duplicates - keep newest “on top”

Question

I need a collection that keeps insertion order and has unique values. LinkedHashSet looks like the way to go, but there\'s one problem - when two items are equal, it removes

Answer 1

All solution provided above are excellent but if we don't want to override already implemented collections. We can solve this problem simply by using an ArrayList with a little trick

We can create a method which you will use to insert data into your list

public static  void addToList(List list, T element) {
    list.remove(element); // Will remove element from list, if list contains it
    list.add(element); // Will add element again to the list 
}

And we can call this method to add element to our list

List list = new ArrayList<>();

addToList(list, "one");
addToList(list, "two");
addToList(list, "three");
addToList(list, "two");

Only disadvantage here is we need to call our custom addToList() method everytime instead of list.add()