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);
}
} |
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);
}
} |
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-