Retaining all elements common in both Queues

 

import java.util.Iterator;

import java.util.PriorityQueue;

class PriorityQueueRetainAll {

public static void main(String[] args) {

// creating our queue

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

pq.add(12);

pq.add(13);

pq.add(14);

pq.add(15);

pq.add(16);

pq.add(17);

pq.add(18);

// creating another queue

PriorityQueue<Integer> pq1 = new PriorityQueue<>();

pq1.add(14);

pq1.add(16);

pq1.add(18);

pq1.add(20);

System.out.println("Queue pq and pq1 before invoking retainAll() method");

System.out.println("pq = " + pq);

System.out.println("pq1 = " + pq1);

pq.retainAll(pq1);

System.out.println("after invoking retainAll() method the queue is");

System.out.println("pq = " + pq);

}

}