Set.remove()
Removes an element from a set.
Available since: Java 1.2
Syntax
boolean remove(Object o)Parameters
| Parameter | Type | Description |
|---|---|---|
| o | Object | The element to remove. |
Return value
boolean`true` if the element was in the set.
Examples
Removing a present and an absent element:
void main() {
Set<String> online = new TreeSet<>(List.of("Anna", "Oleg", "Ivan"));
IO.println(online.remove("Oleg"));
IO.println(online.remove("Maria"));
IO.println(online);
}Output:
true
false
[Anna, Ivan]Notes
An absent element is not an error — the method simply returns false. To remove all elements matching a condition use removeIf().
See also
- Set.add() — Adds an element if it is not in the set yet.
- Set.removeAll() — Removes all elements of another collection from a set (difference).
- Collection.removeIf() — Removes all collection elements that match a condition.
In the tutorial
- Sets: Set — Sets in Java: HashSet without duplicates, LinkedHashSet and TreeSet with ordering, union and intersection of sets.