Below are the add() methods of ArrayList in Java:
-
boolean add(Object o) : This method appends the specified element to the end of this list.
Parameters: object o: The element to be appended to this list. Exception: NA
// Java code to illustrate add(Object o)
import
java.io.*;
import
java.util.ArrayList;
public
class
ArrayListDemo {
public
static
void
main(String[] args)
{
// create an empty array list with an initial capacity
ArrayList<Integer> arrlist =
new
ArrayList<Integer>(
5
);
// use add() method to add elements in the list
arrlist.add(
15
);
arrlist.add(
20
);
arrlist.add(
25
);
// prints all the elements available in list
for
(Integer number : arrlist) {
System.out.println(
"Number = "
+ number);
}
}
}
Output:
Number = 15 Number = 20 Number = 25
-
void add(int index, Object element) : This method inserts the specified element E at the specified position in this list.It shifts the element currently at that position (if any) and any subsequent elements to the right (will add one to their indices).
Parameters: index : The index at which the specified element is to be inserted. element : The element to be inserted. Exception: Throws IndexOutOfBoundsException if the specified index is out of range (index size()).
// Java code to illustrate
// void add(int index, Object element)
import
java.io.*;
import
java.util.ArrayList;
public
class
ArrayListDemo {
public
static
void
main(String[] args)
{
// create an empty array list with an initial capacity
ArrayList<Integer> arrlist =
new
ArrayList<Integer>(
5
);
// use add() method to add elements in the list
arrlist.add(
10
);
arrlist.add(
22
);
arrlist.add(
30
);
arrlist.add(
40
);
// adding element 35 at fourth position
arrlist.add(
3
,
35
);
// let us print all the elements available in list
for
(Integer number : arrlist) {
System.out.println(
"Number = "
+ number);
}
}
}
Output:
Number = 10 Number = 22 Number = 30 Number = 35 Number = 40