用java实现二叉查找树、堆和优先队列

　　优先队列中，元素都赋予了优先级。当访问元素的时候，具有高优先级的元素先移除。优先队列具有高进先出的特性。可以使用堆来实现队列优先。

package priorityQueue;

import heap.Heap;

public class MyPriorityQueue {
 private Heap heap = new Heap();

 public void enqueue(Object newObject) {
  heap.add(newObject);
 }

 public Object dequeue() {
  return heap.remove();
 }

 public int getSize() {
  return heap.getSize();
 }

}

　　测试类：

package priorityQueue;

public class TestPriorityQueue {
 public static void main(String[] args) {
  Patient patient1 = new Patient("john"， 2);
  Patient patient2 = new Patient("slmile"， 0);
  Patient patient3 = new Patient("dohn"， 5);
  Patient patient4 = new Patient("jack"， 3);
  Patient patient5 = new Patient("sen"， 7);

  MyPriorityQueue priorityQueue = new MyPriorityQueue();
  priorityQueue.enqueue(patient1);
  priorityQueue.enqueue(patient2);
  priorityQueue.enqueue(patient3);
  priorityQueue.enqueue(patient4);
  priorityQueue.enqueue(patient5);

  while (priorityQueue.getSize() > 0) {
   System.out.println(priorityQueue.dequeue() + " ");
  }
 }

}

class Patient implements Comparable {
 private String name;
 private int priority;

 public Patient(String name， int priority) {
  this.name = name;
  this.priority = priority;
 }

 public String toString() {
  return name + "(priority: " + priority + ")";
 }

 public int compareTo(Object o) {
  return this.priority - ((Patient) o).priority;
 }
}