package com.delqueue; 
 
import java.util.concurrent.Delayed; 
import java.util.concurrent.TimeUnit; 
 
/** 
 * 消息體定義 實(shí)現(xiàn)Delayed接口就是實(shí)現(xiàn)兩個(gè)方法即compareTo 和 getDelay最重要的就是getDelay方法，這個(gè)方法用來(lái)判斷是否到期…… */ 
public class Message implements Delayed { 
  private int id; 
  private String body; // 消息內(nèi)容 
  private long excuteTime;// 延遲時(shí)長(zhǎng)，這個(gè)是必須的屬性因?yàn)橐凑者@個(gè)判斷延時(shí)時(shí)長(zhǎng)。 
 
  public int getId() { 
    return id; 
  } 
 
  public String getBody() { 
    return body; 
  } 
 
  public long getExcuteTime() { 
    return excuteTime; 
  } 
 
  public Message(int id, String body, long delayTime) { 
    this.id = id; 
    this.body = body; 
    this.excuteTime = TimeUnit.NANOSECONDS.convert(delayTime, TimeUnit.MILLISECONDS) + System.nanoTime(); 
  } 
 
  // 自定義實(shí)現(xiàn)比較方法返回 1 0 -1三個(gè)參數(shù) 
  @Override 
  public int compareTo(Delayed delayed) { 
    Message msg = (Message) delayed; 
    return Integer.valueOf(this.id) > Integer.valueOf(msg.id) ? 1 
        : (Integer.valueOf(this.id) < Integer.valueOf(msg.id) ? -1 : 0); 
  } 
 
  // 延遲任務(wù)是否到時(shí)就是按照這個(gè)方法判斷如果返回的是負(fù)數(shù)則說(shuō)明到期否則還沒(méi)到期 
  @Override 
  public long getDelay(TimeUnit unit) { 
    return unit.convert(this.excuteTime - System.nanoTime(), TimeUnit.NANOSECONDS); 
  } 
}

package com.delqueue; 
 
import java.util.concurrent.DelayQueue; 
 
public class Consumer implements Runnable { 
  // 延時(shí)隊(duì)列 ,消費(fèi)者從其中獲取消息進(jìn)行消費(fèi) 
  private DelayQueue<Message> queue; 
 
  public Consumer(DelayQueue<Message> queue) { 
    this.queue = queue; 
  } 
 
  @Override 
  public void run() { 
    while (true) { 
      try { 
        Message take = queue.take(); 
        System.out.println("消費(fèi)消息id：" + take.getId() + " 消息體：" + take.getBody()); 
      } catch (InterruptedException e) { 
        e.printStackTrace(); 
      } 
    } 
  } 
}

package com.delqueue; 
 
import java.util.concurrent.DelayQueue; 
import java.util.concurrent.ExecutorService; 
import java.util.concurrent.Executors; 
 
public class DelayQueueTest { 
   public static void main(String[] args) {  
      // 創(chuàng)建延時(shí)隊(duì)列  
      DelayQueue<Message> queue = new DelayQueue<Message>();  
      // 添加延時(shí)消息,m1 延時(shí)3s  
      Message m1 = new Message(1, "world", 3000);  
      // 添加延時(shí)消息,m2 延時(shí)10s  
      Message m2 = new Message(2, "hello", 10000);  
      //將延時(shí)消息放到延時(shí)隊(duì)列中 
      queue.offer(m2);  
      queue.offer(m1);  
      // 啟動(dòng)消費(fèi)線程 消費(fèi)添加到延時(shí)隊(duì)列中的消息，前提是任務(wù)到了延期時(shí)間  
      ExecutorService exec = Executors.newFixedThreadPool(1); 
      exec.execute(new Consumer(queue)); 
      exec.shutdown(); 
    }  
}

package com.test.delayqueue; 
/** 
 * 具體執(zhí)行相關(guān)業(yè)務(wù)的業(yè)務(wù)類(lèi) 
 * @author whd 
 * @date 2017年9月25日 上午12:49:32 
 */ 
public class DelayOrderWorker implements Runnable { 
 
  @Override 
  public void run() { 
    // TODO Auto-generated method stub 
    //相關(guān)業(yè)務(wù)邏輯處理 
    System.out.println(Thread.currentThread().getName()+" do something ……"); 
  } 
}

package com.test.delayqueue; 
 
import java.util.concurrent.Delayed; 
import java.util.concurrent.TimeUnit; 
 
/** 
 * 延時(shí)隊(duì)列中的消息體將任務(wù)封裝為消息體 
 * 
 * @author whd 
 * @date 2017年9月25日 上午12:48:30 
 * @param <T> 
 */ 
public class DelayOrderTask<T extends Runnable> implements Delayed { 
  private final long time; 
  private final T task; // 任務(wù)類(lèi)，也就是之前定義的任務(wù)類(lèi) 
 
  /** 
   * @param timeout 
   *      超時(shí)時(shí)間(秒) 
   * @param task 
   *      任務(wù) 
   */ 
  public DelayOrderTask(long timeout, T task) { 
    this.time = System.nanoTime() + timeout; 
    this.task = task; 
  } 
 
  @Override 
  public int compareTo(Delayed o) { 
    // TODO Auto-generated method stub 
    DelayOrderTask other = (DelayOrderTask) o; 
    long diff = time - other.time; 
    if (diff > 0) { 
      return 1; 
    } else if (diff < 0) { 
      return -1; 
    } else { 
      return 0; 
    } 
  } 
 
  @Override 
  public long getDelay(TimeUnit unit) { 
    // TODO Auto-generated method stub 
    return unit.convert(this.time - System.nanoTime(), TimeUnit.NANOSECONDS); 
  } 
 
  @Override 
  public int hashCode() { 
    return task.hashCode(); 
  } 
 
  public T getTask() { 
    return task; 
  } 
}

package com.test.delayqueue; 
 
import java.util.Map; 
import java.util.concurrent.DelayQueue; 
import java.util.concurrent.ExecutorService; 
import java.util.concurrent.Executors; 
import java.util.concurrent.TimeUnit; 
import java.util.concurrent.atomic.AtomicLong; 
 
/** 
 * 延時(shí)隊(duì)列管理類(lèi)，用來(lái)添加任務(wù)、執(zhí)行任務(wù) 
 * 
 * @author whd 
 * @date 2017年9月25日 上午12:44:59 
 */ 
public class DelayOrderQueueManager { 
  private final static int DEFAULT_THREAD_NUM = 5; 
  private static int thread_num = DEFAULT_THREAD_NUM; 
  // 固定大小線程池 
  private ExecutorService executor; 
  // 守護(hù)線程 
  private Thread daemonThread; 
  // 延時(shí)隊(duì)列 
  private DelayQueue<DelayOrderTask<?>> delayQueue; 
  private static final AtomicLong atomic = new AtomicLong(0); 
  private final long n = 1; 
  private static DelayOrderQueueManager instance = new DelayOrderQueueManager(); 
 
  private DelayOrderQueueManager() { 
    executor = Executors.newFixedThreadPool(thread_num); 
    delayQueue = new DelayQueue<>(); 
    init(); 
  } 
 
  public static DelayOrderQueueManager getInstance() { 
    return instance; 
  } 
 
  /** 
   * 初始化 
   */ 
  public void init() { 
    daemonThread = new Thread(() -> { 
      execute(); 
    }); 
    daemonThread.setName("DelayQueueMonitor"); 
    daemonThread.start(); 
  } 
 
  private void execute() { 
    while (true) { 
      Map<Thread, StackTraceElement[]> map = Thread.getAllStackTraces(); 
      System.out.println("當(dāng)前存活線程數(shù)量:" + map.size()); 
      int taskNum = delayQueue.size(); 
      System.out.println("當(dāng)前延時(shí)任務(wù)數(shù)量:" + taskNum); 
      try { 
        // 從延時(shí)隊(duì)列中獲取任務(wù) 
        DelayOrderTask<?> delayOrderTask = delayQueue.take(); 
        if (delayOrderTask != null) { 
          Runnable task = delayOrderTask.getTask(); 
          if (null == task) { 
            continue; 
          } 
          // 提交到線程池執(zhí)行task 
          executor.execute(task); 
        } 
      } catch (Exception e) { 
        e.printStackTrace(); 
      } 
    } 
  } 
 
  /** 
   * 添加任務(wù) 
   * 
   * @param task 
   * @param time 
   *      延時(shí)時(shí)間 
   * @param unit 
   *      時(shí)間單位 
   */ 
  public void put(Runnable task, long time, TimeUnit unit) { 
    // 獲取延時(shí)時(shí)間 
    long timeout = TimeUnit.NANOSECONDS.convert(time, unit); 
    // 將任務(wù)封裝成實(shí)現(xiàn)Delayed接口的消息體 
    DelayOrderTask<?> delayOrder = new DelayOrderTask<>(timeout, task); 
    // 將消息體放到延時(shí)隊(duì)列中 
    delayQueue.put(delayOrder); 
  } 
 
  /** 
   * 刪除任務(wù) 
   * 
   * @param task 
   * @return 
   */ 
  public boolean removeTask(DelayOrderTask task) { 
 
    return delayQueue.remove(task); 
  } 
}

package com.delqueue; 
 
import java.util.concurrent.TimeUnit; 
 
import com.test.delayqueue.DelayOrderQueueManager; 
import com.test.delayqueue.DelayOrderWorker; 
 
public class Test { 
  public static void main(String[] args) { 
    DelayOrderWorker work1 = new DelayOrderWorker();// 任務(wù)1 
    DelayOrderWorker work2 = new DelayOrderWorker();// 任務(wù)2 
    DelayOrderWorker work3 = new DelayOrderWorker();// 任務(wù)3 
    // 延遲隊(duì)列管理類(lèi)，將任務(wù)轉(zhuǎn)化消息體并將消息體放入延遲對(duì)列中等待執(zhí)行 
    DelayOrderQueueManager manager = DelayOrderQueueManager.getInstance(); 
    manager.put(work1, 3000, TimeUnit.MILLISECONDS); 
    manager.put(work2, 6000, TimeUnit.MILLISECONDS); 
    manager.put(work3, 9000, TimeUnit.MILLISECONDS); 
  } 
 
}

rabbitmq_delayed_message_exchange

wget https://bintray.com/rabbitmq/community-plugins/download_file?file_path=rabbitmq_delayed_message_exchange-0.0.1.ez

rabbitmq-plugins enable rabbitmq_delayed_message_exchange

rabbitmq-plugins disable rabbitmq_delayed_message_exchange

x-delay

消息發(fā)送時(shí)間:2018-05-03 12:44:53
3秒鐘后，Spring Boot控制臺(tái)會(huì)輸出:
消息接收時(shí)間:2018-05-03 12:44:56
接收到的消息:hello i am delay msg