Java ArrayList add() Method
Example
Add an item to a list:
import java.util.ArrayList;
public class Main {
public static void main(String[] args) {
ArrayList<String> cars = new ArrayList<String>();
cars.add("Volvo");
cars.add("BMW");
cars.add("Ford");
cars.add("Mazda");
System.out.println(cars);
}
}
Definition and Usage
The add() method adds an item to the list.
If an index is provided then the new item will be placed at the specified index, pushing all of the following elements in the list ahead by one.
If an index is not provided then the new item will be placed at the end of the list.
Syntax
One of the following:
public boolean add(T item)public void add(int index, T item)T refers to the data type of items in the list.
Parameter Values
| Parameter | Description |
|---|---|
| index | Optional. The position in the list at which to add the item. |
| item | Required. The item to be added to the list. |
Technical Details
| Returns: | Nothing if an index is specified. When an index is not specified it returns true if the list changed and false if the list did not change. |
|---|---|
| Throws: | IndexOutOfBoundsException - If the index is less than zero or greater than the size of the list. |
More Examples
Example
Add an item at a specified position in the list:
import java.util.ArrayList;
public class Main {
public static void main(String[] args) {
ArrayList<String> cars = new ArrayList<String>();
cars.add("Volvo");
cars.add("BMW");
cars.add("Ford");
cars.add("Mazda");
cars.add(2, "Toyota");
System.out.println(cars);
}
}
Related Pages
❮ ArrayList Methods
