List.set()
Replaces the list element at an index.
Available since: Java 1.2
Syntax
E set(int index, E element)Parameters
| Parameter | Type | Description |
|---|---|---|
| index | int | The position of the element to replace. |
| element | E | The new value. |
Return value
EThe element that was at this position before.
Examples
Replacing the second element:
void main() {
List<String> colors = new ArrayList<>(List.of("red", "green", "blue"));
String old = colors.set(1, "yellow");
IO.println(old);
IO.println(colors);
}Output:
green
[red, yellow, blue]Notes
The list size does not change: set() replaces rather than inserts. To insert use add(index, element). The index must exist, otherwise IndexOutOfBoundsException is thrown.
See also
- List.get() — Returns the list element at an index.
- List.add() — Adds an element to the end of a list or at a given position.
- List.replaceAll() — Replaces every list element with the result of a function.
In the tutorial
- Lists: List and ArrayList — Lists in Java: ArrayList, adding, reading and removing elements, unmodifiable List.of lists and lists of numbers.