The add(E e) method of CopyOnWriteArraySet inserts the element passed in the parameter to the end of the Set or at a specified index in the Set. The function returns true on addition of new element to the Set.
Syntax:
public boolean add(E e)
Parameters: The function accepts a single mandatory parameter element which specifies the element to be added in the Set.
Return Value: The function returns true on addition in the Set.
Below programs illustrate the above function:
Program 1:
// Java Program to illustrate the CopyOnWriteArraySet// add(element) method in Java  import java.util.concurrent.CopyOnWriteArraySet;import java.util.*;  public class GFG {    public static void main(String[] args)    {          // create object of CopyOnWriteArraySet        CopyOnWriteArraySet<Integer> ArrSet            = new CopyOnWriteArraySet<Integer>();          // Add elements        ArrSet.add(2);        ArrSet.add(3);        ArrSet.add(4);        ArrSet.add(7);          // print CopyOnWriteArraySet        System.out.println("CopyOnWriteArraySet: "                           + ArrSet);          // 4 is already present hence cannot add        System.out.println("On adding 4 it returns "                           + ArrSet.add(4));          // print CopyOnWriteArraySet        System.out.println("Updated CopyOnWriteArraySet: "                           + ArrSet);    }} |
Output:
CopyOnWriteArraySet: [2, 3, 4, 7] On adding 4 it returns false Updated CopyOnWriteArraySet: [2, 3, 4, 7]
Program 2:
// Java Program to illustrate the CopyOnWriteArraySet// add(element) method in Java  import java.util.concurrent.CopyOnWriteArraySet;import java.util.*;  public class GFG {    public static void main(String[] args)    {          // create object of CopyOnWriteArraySet        CopyOnWriteArraySet<Integer> ArrSet            = new CopyOnWriteArraySet<Integer>();          // Add elements        ArrSet.add(2);        ArrSet.add(3);        ArrSet.add(3);        ArrSet.add(3);          // print CopyOnWriteArraySet        System.out.println("CopyOnWriteArraySet: "                           + ArrSet);          // 45 is not present hence add        System.out.println("On adding 45 it returns "                           + ArrSet.add(45));          // print CopyOnWriteArraySet        System.out.println("Updated CopyOnWriteArraySet: "                           + ArrSet);    }} |
Output:
CopyOnWriteArraySet: [2, 3] On adding 45 it returns true Updated CopyOnWriteArraySet: [2, 3, 45]
Reference: https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/CopyOnWriteArraySet.html#add-E-
