LinkedTransferQueue add() method in Java

// Java Program Demonstrate add()
// method of LinkedTransferQueue

import java.util.concurrent.*;

class LinkedTransferQueueAddExample1 {
    public static void main(String[] args)
    {

        // Initializing the queue
        LinkedTransferQueue<Integer>
            queue = new LinkedTransferQueue<Integer>();

        // Adding elements to this queue
        for (int i = 10; i <= 15; i++)
            queue.add(i);

        // Printing the elements of the queue
        System.out.println("The elements in the queue are:");
        for (Integer i : queue)
            System.out.print(i + " ");
    }
}

// Java Program Demonstrate add()
// method of LinkedTransferQueue

import java.util.concurrent.*;

class LinkedTransferQueueAddExample2 {
    public static void main(String[] args)
    {

        // Initializing the queue
        LinkedTransferQueue<String>
            queue = new LinkedTransferQueue<String>();

        // Adding elements to this queue
        queue.add("a");
        queue.add("b");
        queue.add("c");
        queue.add("d");
        queue.add("e");

        // Printing the elements of the queue
        System.out.println("The elements in the queue are:");
        for (String i : queue)
            System.out.print(i + " ");
    }
}

// Java Program Demonstrate add()
// method of LinkedTransferQueue

import java.util.concurrent.*;

class LinkedTransferQueueAddExample2 {
    public static void main(String[] args)
    {

        // Initializing the queue
        LinkedTransferQueue<String>
            queue = new LinkedTransferQueue<String>();

        try {
            // Adding null to this queue
            queue.add(null);
        }
        catch (Exception e) {
            System.out.println("Exception: " + e);
        }
    }
}