Java Collection, PriorityQueue Exercises: Count the number of elements in a priority queue

Java Collection, PriorityQueue Exercises: Exercise-6 with Solution

Write a Java program to count the number of elements in a priority queue.

Sample Solution:-

Java Code:

import java.util.PriorityQueue;
  public class Exercise6 {
  public static void main(String[] args) {
    // create an empty Priority Queue
    PriorityQueue<String> pq = new PriorityQueue<String>();  
   // use add() method to add values in the Priority Queue
     System.out.println("Priority Queue: " + pq);
    System.out.println("Size of the Priority Queue: " + pq.size());

Sample Output:

Priority Queue: [Black, Pink, Green, Red, orange]                      
Size of the Priority Queue: 5

Java Code Editor:

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Java: Tips of the Day


Converts to enum to Map where key is the name and value is Enum itself.

public static <E extends Enum<E>> Map<String, E> getEnumMap(final Class<E> enumClass) {
    return Arrays.stream(enumClass.getEnumConstants())
            .collect(Collectors.toMap(Enum::name, Function.identity()));

Ref: https://bit.ly/3xXcFZt