Java by API/java.util/PriorityQueue

new PriorityQueue(int initialCapacity)

   <source lang="java">

import java.util.ruparator; import java.util.PriorityQueue; enum ProductQuality {

 High, Medium, Low

} class Product implements Comparable<Product> {

 String name;
 ProductQuality priority;
 Product(String str, ProductQuality pri) {
   name = str;
   priority = pri;
 }
 public int compareTo(Product msg2) {
   return priority.rupareTo(msg2.priority);
 }

} class MessageComparator implements Comparator<Product> {

 public int compare(Product msg1, Product msg2) {
   return msg2.priority.rupareTo(msg1.priority);
 }

} public class Main {

 public static void main(String args[]) {
   PriorityQueue<Product> pq = new PriorityQueue<Product>(3);
   pq.add(new Product("A", ProductQuality.Low));
   pq.add(new Product("B", ProductQuality.High));
   pq.add(new Product("C", ProductQuality.Medium));
   Product m;
   while ((m = pq.poll()) != null)
     System.out.println(m.name + " Priority: " + m.priority);
   PriorityQueue<Product> pqRev = new PriorityQueue<Product>(3, new MessageComparator());
   pqRev.add(new Product("D", ProductQuality.Low));
   pqRev.add(new Product("E", ProductQuality.High));
   pqRev.add(new Product("F", ProductQuality.Medium));
   while ((m = pqRev.poll()) != null)
     System.out.println(m.name + " Priority: " + m.priority);
 }

}

 </source>
   
  
 
  

PriorityQueue: poll()

   <source lang="java">

import java.util.ruparator; import java.util.PriorityQueue; enum ProductQuality {

 High, Medium, Low

} class Product implements Comparable<Product> {

 String name;
 ProductQuality priority;
 Product(String str, ProductQuality pri) {
   name = str;
   priority = pri;
 }
 public int compareTo(Product msg2) {
   return priority.rupareTo(msg2.priority);
 }

} class MessageComparator implements Comparator<Product> {

 public int compare(Product msg1, Product msg2) {
   return msg2.priority.rupareTo(msg1.priority);
 }

} public class Main {

 public static void main(String args[]) {
   PriorityQueue<Product> pq = new PriorityQueue<Product>(3);
   pq.add(new Product("A", ProductQuality.Low));
   pq.add(new Product("B", ProductQuality.High));
   pq.add(new Product("C", ProductQuality.Medium));
   Product m;
   while ((m = pq.poll()) != null)
     System.out.println(m.name + " Priority: " + m.priority);
   PriorityQueue<Product> pqRev = new PriorityQueue<Product>(3, new MessageComparator());
   pqRev.add(new Product("D", ProductQuality.Low));
   pqRev.add(new Product("E", ProductQuality.High));
   pqRev.add(new Product("F", ProductQuality.Medium));
   while ((m = pqRev.poll()) != null)
     System.out.println(m.name + " Priority: " + m.priority);
 }

}

 </source>