Creat a PriorityQueue class that uses a binary minheap for i

Creat a PriorityQueue class that uses a binary min-heap for its implementation. The constructor will takes one argument, the initial size of a queue.

1) public void add(T e) - Inserts the specified element \'e\' into this priority queue. Throws NullPointerException if the specified element is null.

2) public T poll() Retrieves the head of the this priority queue (smallest element), or null if the queue is empty.

Solution

//PriorityQueue implemention with binary min heap program in java

package com.chegg;

import java.util.PriorityQueue;

public class PriorityQueue1 {
       PriorityQueue<Integer> pq ;
      
   //Constructor which takes an argument size
   public PriorityQueue1(int size) {
           pq = new PriorityQueue<Integer>(size);
   }
  
   //inserts the element returns and throws null pointer exception if the element is null
   public void add(int[] x) {
       try{
       for (int i = 0; i < x.length; i++) {
           pq.offer(x[i]);
       }}
       catch(NullPointerException ne){
           ne.printStackTrace();
       }
   }
  
   //Retrieves the head of this queue.
   public Integer poll(){
           return pq.poll();
   }
  
   //Prints the elements of Priority Queue
   public void print() {
       System.out.println(pq);
   }
  
   public static void main(String[] args) {
       int[] x = { 1, 6, 2, 9, 4, 3, 8 };
      
       PriorityQueue1 pq = new PriorityQueue1(10);
       pq.add(x);
       pq.print();
      
       System.out.println(\"The head of the Queue is: \"+pq.poll());
      
       pq.print();
      
  

   }

}

Output:

[1, 4, 2, 9, 6, 3, 8]

The head of the Queue is: 1

[2, 4, 3, 9, 6, 8]