LinkedBlockingDeque size() method in Java

The size() method of LinkedBlockingDeque returns the current size of the Deque container. On calling the function the number of elements in the Deque container is returned. If the container is capacity restricted, then also it returns the number of elements which are present in the container at the time of function call.

Syntax:

public int size()

Returns: This method returns an integer value which signifies the number of elements in the container.

Below programs illustrate size() method of LinkedBlockingDeque:

Program 1:

// Java Program to demonstrate public int size()
// method of LinkedBlockingDeque

import java.util.concurrent.LinkedBlockingDeque;
import java.util.*;

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

        // create object of LinkedBlockingDeque
        LinkedBlockingDeque<Integer> LBD
            = new LinkedBlockingDeque<Integer>();

        // Add numbers to end of LinkedBlockingDeque
        LBD.add(15);
        LBD.add(20);
        LBD.add(20);
        LBD.add(15);
        LBD.add(15);
        LBD.add(20);
        LBD.add(20);
        LBD.add(15);

        // print Dequeue
        System.out.println("Linked Blocking Deque: " + LBD);

        // prints the Deque after removal
        System.out.println("Size of Linked Blocking Deque: "
                           + LBD.size());
    }
}

Output:

Linked Blocking Deque: [15, 20, 20, 15, 15, 20, 20, 15]
Size of Linked Blocking Deque: 8

Program 2:

// Java Program to demonstrate public int size()
// method of LinkedBlockingDeque

import java.util.concurrent.LinkedBlockingDeque;
import java.util.*;

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

        // create object of LinkedBlockingDeque
        LinkedBlockingDeque<String> LBD
            = new LinkedBlockingDeque<String>();

        // Add numbers to end of LinkedBlockingDeque
        LBD.add("geeks");
        LBD.add("forGeeks");
        LBD.add("A Computer");
        LBD.add("Portal");

        // print Dequeue
        System.out.println("Linked Blocking Deque: " + LBD);

        // prints the Deque after removal
        System.out.println("Size of Linked Blocking Deque: "
                           + LBD.size());
    }
}

Output:

Linked Blocking Deque: [geeks, forGeeks, A Computer, Portal]
Size of Linked Blocking Deque: 4

Reference: https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/LinkedBlockingDeque.html#size–