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The isEmpty(E e) method of CopyOnWriteArraySet checks if the Set is empty or not. It returns true if the Set is empty, else it returns false.

Syntax:

public boolean isEmpty()

Return Value: The function returns true if the Set is empty, otherwise it returns false.

Below programs illustrate the above function:

Program 1:

Java

// Java Program to illustrate the
// isEmpty() method in CopyOnWriteArraySet

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(32);
        ArrSet.add(67);
        ArrSet.add(98);
        ArrSet.add(100);

        // print CopyOnWriteArraySet
        System.out.println("CopyOnWriteArraySet: " + ArrSet);

        // check using function
        if (ArrSet.isEmpty())
            System.out.println("\nSet is empty");
        else
            System.out.println("\nSet is not empty");
    }
}

Output:

CopyOnWriteArraySet: [32, 67, 98, 100]

Set is not empty

Program 2:

Java

// Java Program to illustrate the
// isEmpty() method in CopyOnWriteArraySet
import java.util.concurrent.CopyOnWriteArraySet;
import java.util.*;

public class GFG {
    public static void main(String[] args)
    {

        // create object of CopyOnWriteArraySet
        CopyOnWriteArraySet<String> ArrSet
            = new CopyOnWriteArraySet<String>();

        // print CopyOnWriteArraySet
        System.out.println("CopyOnWriteArraySet: "
                           + ArrSet);

        // check using function
        if (ArrSet.isEmpty())
            System.out.println("\nSet is empty");
        else
            System.out.println("\nSet is not empty");
    }
}

Output:

CopyOnWriteArraySet: []

Set is empty

Reference: https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/CopyOnWriteArraySet.html#isEmpty--

CopyOnWriteArraySet isEmpty() method in Java

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