In this program, we will create 2 queues using the Queue interface with the help of Linked List collection and store elements in a FIFO (First In First Out) manner. Then we will check whether queues are empty or not using the isEmpty() method.
Program/Source Code:
The source code to check whether a queue is empty or not is given below. The given program is compiled and executed successfully.
// Java program to check a queue is empty or not
import java.util.LinkedList;
import java.util.Queue;
public class Main {
public static void main(String[] args) {
Queue < Integer > queue = new LinkedList < > ();
Queue < Integer > emQueue = new LinkedList < > ();
queue.add(10);
queue.add(20);
queue.add(30);
queue.add(40);
queue.add(50);
if (queue.isEmpty())
System.out.println("The queue is empty.");
else
System.out.println("The queue is not empty.");
if (emQueue.isEmpty())
System.out.println("The emQueue is empty.");
else
System.out.println("The emQueue is not empty.");
}
}
Output:
The queue is not empty.
The emQueue is empty.
Explanation:
In the above program, we imported the "java.util.LinkedList" and "java.util.Queue" packages to use the Queue Interface and LinkedList collection respectively. Here, we created a class Main. The Main class contains a main() method. The main() method is the entry point for the program.
In the main() method, we created 2 queues using LinkedList collection and added items to it. Then we checked whether queues are empty or not using the isEmpty() method and printed the appropriate message.
In this program, we will create 2 queues using the Queue interface with the help of Linked List collection and store elements in a FIFO (First In First Out) manner. Then we will check whether queues are empty or not using the isEmpty() method.
Program/Source Code:
The source code to check whether a queue is empty or not is given below. The given program is compiled and executed successfully.
Output:
Explanation:
In the above program, we imported the "java.util.LinkedList" and "java.util.Queue" packages to use the Queue Interface and LinkedList collection respectively. Here, we created a class Main. The Main class contains a main() method. The main() method is the entry point for the program.
In the main() method, we created 2 queues using LinkedList collection and added items to it. Then we checked whether queues are empty or not using the isEmpty() method and printed the appropriate message.