PriorityQueue remove() in Java

remove(): This method is available in java.util.PriorityQueue class of Java.

Syntax:

K java.util.AbstractQueue.remove()

This method retrieves and removes the head of this queue.

Parameters: NA

Returns: the head of this queue.

Throws:

NoSuchElementException - if this queue is empty

Approach 1: When no exception

Java

import java.util.PriorityQueue;

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

        PriorityQueue<Integer> priorityQueue =
               new PriorityQueue<Integer>();

        priorityQueue.add(12);
        priorityQueue.add(5);
        priorityQueue.add(10);
        priorityQueue.add(2);

        System.out.println(priorityQueue.remove());

    }
}

Output:

2

Approach 2: NoSuchElementException 

Java

import java.util.PriorityQueue;

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

        PriorityQueue<Integer> priorityQueue = 
                   new PriorityQueue<Integer>();

        System.out.println(priorityQueue.remove());

    }
}

Output:

Exception in thread "main" java.util.NoSuchElementException
	at java.base/java.util.AbstractQueue.remove(AbstractQueue.java:117)