Java by API/java.util/PriorityQueue

new PriorityQueue(int initialCapacity)

 


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);
  }
}

PriorityQueue: poll()

 

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);
  }
}