The size() method of BlockingDeque 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.
Note: The size() method of BlockingDeque has been inherited from the LinkedBlockingDeque class in Java.
Below programs illustrate size() method of BlockingDeque:
Program 1:
// Java Program to demonstrate public int size()// method of BlockingDeque  import java.util.concurrent.LinkedBlockingDeque;import java.util.concurrent.BlockingDeque;import java.util.*;  public class GFG {    public static void main(String[] args)        throws InterruptedException    {          // create object of BlockingDeque        BlockingDeque<Integer> BD            = new LinkedBlockingDeque<Integer>();          // Add numbers to end of BlockingDeque        BD.add(15);        BD.add(20);        BD.add(20);        BD.add(15);        BD.add(15);        BD.add(20);        BD.add(20);        BD.add(15);          // print Deque        System.out.println("Blocking Deque: " + BD);          // prints the Deque after removal        System.out.println("Size of Blocking Deque: "                           + BD.size());    }} |
Output:
Blocking Deque: [15, 20, 20, 15, 15, 20, 20, 15] Size of Blocking Deque: 8
Program 2:
// Java Program to demonstrate public int size()// method of BlockingDeque  import java.util.concurrent.LinkedBlockingDeque;import java.util.concurrent.BlockingDeque;import java.util.*;  public class GFG {    public static void main(String[] args)        throws InterruptedException    {          // create object of BlockingDeque        BlockingDeque<String> BD            = new LinkedBlockingDeque<String>();          // Add numbers to end of BlockingDeque        BD.add("geeks");        BD.add("forGeeks");        BD.add("A Computer");        BD.add("Portal");          // print Dequeue        System.out.println("Blocking Deque: " + BD);          // prints the Deque after removal        System.out.println("Size of Blocking Deque: "                           + BD.size());    }} |
Output:
Blocking Deque: [geeks, forGeeks, A Computer, Portal] Size of Blocking Deque: 4
Reference: https://docs.oracle.com/javase/7/docs/api/java/util/concurrent/BlockingDeque.html#size()
