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The isEmpty(E e) method of CopyOnWriteArrayList checks if the list is empty or not. It returns true if the list is empty, else it returns false. Syntax:

public boolean isEmpty()

Parameters: The function does not accepts any parameter. Return Value: The function returns true if the list is empty, otherwise it returns false. Below programs illustrate the above function: Program 1:

Java

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

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

        // create object of CopyOnWriteArrayList
        CopyOnWriteArrayList<Integer> ArrLis
            = new CopyOnWriteArrayList<Integer>();

        // Add elements
        ArrLis.add(32);
        ArrLis.add(67);
        ArrLis.add(98);
        ArrLis.add(100);

        // print CopyOnWriteArrayList
        System.out.println("CopyOnWriteArrayList: " + ArrLis);

        // check using function
        if (ArrLis.isEmpty())
            System.out.println("List is empty");
        else
            System.out.println("List is not empty");

        ArrLis.clear();

        // check using function
        if (ArrLis.isEmpty())
            System.out.println("List is empty");
        else
            System.out.println("List is not empty");
    }
}

Output:

CopyOnWriteArrayList: [32, 67, 98, 100]
List is not empty
List is empty

Program 2:

Java

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

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

        // create object of CopyOnWriteArrayList
        CopyOnWriteArrayList<String> ArrLis
            = new CopyOnWriteArrayList<String>();

        // Add elements
        ArrLis.add("gopal");
        ArrLis.add("gfg");
        ArrLis.add("jgec");
        ArrLis.add("sudo");

        // print CopyOnWriteArrayList
        System.out.println("CopyOnWriteArrayList: " + ArrLis);

        // check using function
        if (ArrLis.isEmpty())
            System.out.println("List is empty");
        else
            System.out.println("List is not empty");

        ArrLis.clear();

        // check using function
        if (ArrLis.isEmpty())
            System.out.println("List is empty");
        else
            System.out.println("List is not empty");
    }
}

Output:

CopyOnWriteArrayList: [gopal, gfg, jgec, sudo]
List is not empty
List is empty

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

CopyOnWriteArrayList isEmpty() method in Java

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