کالکشن ها در جاوا: استفاده از صف اولویتی (PriorityQueue)

PriorityQueue<String> priorityQueue = new PriorityQueue<>();
priorityQueue.offer("Tehran");
priorityQueue.offer("Arak");
priorityQueue.offer("Shiraz");
priorityQueue.offer("Qazvin");
priorityQueue.offer("Mashhad");
priorityQueue.offer("Qom");
priorityQueue.offer("Zanjan");
priorityQueue.offer("Zahedan");

while(!priorityQueue.isEmpty())
    System.out.print(priorityQueue.poll() + " ");
        

PriorityQueue<String> priorityQueue = new PriorityQueue<>(new Comparator<>() {
    @Override
    public int compare(String o1, String o2) {
        if (o1.length() > o2.length())
            return 1;
        else if (o1.length() < o2.length())
            return -1;
        else 
            return 0;
    }
});

priorityQueue.offer("Tehran");
priorityQueue.offer("Arak");
priorityQueue.offer("Shiraz");
priorityQueue.offer("Qazvin");
priorityQueue.offer("Mashhad");
priorityQueue.offer("Qom");
priorityQueue.offer("Zanjan");
priorityQueue.offer("Zahedan");

while (!priorityQueue.isEmpty())
    System.out.print(priorityQueue.poll() + " ");
        

PriorityQueue<String> priorityQueue = new PriorityQueue<>((o1, o2) -> {
    if (o1.length() > o2.length())
        return 1;
    else if (o1.length() < o2.length())
        return -1;
    else return 0;
});
        

PriorityQueue<Integer> priorityQueue2 = new PriorityQueue<>(Comparator.reverseOrder());
priorityQueue2.offer(42);
priorityQueue2.offer(54);
priorityQueue2.offer(32);
priorityQueue2.offer(71);
priorityQueue2.offer(12);
priorityQueue2.offer(25);
priorityQueue2.offer(62);

while (!priorityQueue2.isEmpty())
    System.out.print(priorityQueue2.poll() + " ");
        

public class TaskManagerDemo {

    public static void main(String[] args) {

        PriorityQueue<Task> tasks = new PriorityQueue<>();

        tasks.offer(new Task(Task.Priority.HIGH, "Power Off");
        tasks.offer(new Task(Task.Priority.HIGH, "Delete File"));
        tasks.offer(new Task(Task.Priority.LOW, "Play Music"));
        tasks.offer(new Task(Task.Priority.MEDIUM, "Run Text Editor"));
        tasks.offer(new Task(Task.Priority.LOW, "Close Browser"));

        while (!tasks.isEmpty())
            tasks.poll().run();

    }

    private static class Task implements Comparable<Task> {

        private final Priority priority;
        private final String name;

        public Task(Priority priority, String name) {
            this.priority = priority;
            this.name = name;
        }

        public Priority getPriority() {
            return priority;
        }

        public void run() {
            System.out.printf("Running task: %-20s" + " Priority Number: %1d\n", name, priority.getPriorityNumber());
        }

        @Override
        public int compareTo(Task t) {
            return Integer.compare(priority.getPriorityNumber(), t.getPriority().getPriorityNumber());
        }

        enum Priority {
            HIGH(1), MEDIUM(2), LOW(3);

            private final int priorityNumber;

            Priority(int priorityNumber) {
                this.priorityNumber = priorityNumber;
            }

            public int getPriorityNumber() {
                return priorityNumber;
            }
        }
    }
}