package test;
import java.util.PriorityQueue;
public class PriorityQueueTest1 {
 @SuppressWarnings("unchecked")
 public static void main(String[] args) {
 PriorityQueue queue = new PriorityQueue();
 queue.add("AAAAA"); // Add接受的參數(shù)是Obj，PriorityQueue使用integer String等基本的數(shù)據(jù)類型時(shí)，默認(rèn)new時(shí)有參數(shù)，如果不寫則是按照默認(rèn)排序
 queue.add("BBBBB"); 
 queue.add("CCCCC"); 
 queue.add("DDDDD"); 
 
 System.out.println(queue.peek()); // 獲取但不移除此隊(duì)列的頭
 System.out.println(queue.poll()); // 獲取并移除此隊(duì)列的頭
 System.out.println(queue.poll());
 
 queue.offer("ZZZZZ"); // 將指定的元素插入此優(yōu)先級(jí)隊(duì)列
 
 System.out.println(queue.poll());
 System.out.println(queue.poll());
 System.out.println(queue.poll());
 
 System.out.println(queue.poll()); // 到這里已經(jīng)沒有元素，打印Null
 }
}

package test;
import java.util.Comparator;
import java.util.PriorityQueue;
@SuppressWarnings("unchecked")
public class PriorityQueueTest2 {
 private static PriorityQueue queue = new PriorityQueue(10,new Comparators());
 public static void main(String[] args) {
 QueueObject queueObject = new QueueObject();
 queueObject.setId(4);
 queueObject.setObject("AAAAA");
 queue.add(queueObject);
 QueueObject queueObject1 = new QueueObject();
 queueObject1.setId(1);
 queueObject1.setObject("BBBBB");
 queue.add(queueObject1);
 QueueObject queueObject2 = new QueueObject();
 queueObject2.setId(3);
 queueObject2.setObject("CCCCC");
 queue.add(queueObject2);
 
 System.out.println(((QueueObject)queue.poll()).getObject());
 System.out.println(((QueueObject)queue.poll()).getObject());
 System.out.println(((QueueObject)queue.poll()).getObject());
 }
}
class QueueObject {
  private int id;
  private Object object;
  public int getId() {
    return id;
  }
  public void setId(int id) {
    this.id = id;
  }
  public Object getObject() {
    return object;
  }
  public void setObject(Object object) {
    this.object = object;
  }
}
@SuppressWarnings("unchecked")
class Comparators implements Comparator{
  public int compare(Object arg0, Object arg1) {
    int val1 = ((QueueObject)arg0).getId();
    int val2 = ((QueueObject)arg1).getId();
    return val1 < val2 ? 0 : 1;
  }
}