springboot执行延时任务之DelayQueue的使用详解

public interface Delayed extends Comparable<Delayed> {

 /**
  * Returns the remaining delay associated with this object, in the
  * given time unit.
  *
  * @param unit the time unit
  * @return the remaining delay; zero or negative values indicate
  * that the delay has already elapsed
  */
 long getDelay(TimeUnit unit);
}

import java.util.Date;
import java.util.concurrent.Delayed;
import java.util.concurrent.TimeUnit;
public class DelayTask implements Delayed {
 final private TaskBase data;
 final private long expire;
 /**
  * 构造延时任务
  * @param data  业务数据
  * @param expire 任务延时时间（ms）
  */
 public DelayTask(TaskBase data, long expire) {
  super();
  this.data = data;
  this.expire = expire + System.currentTimeMillis();
 }
 public TaskBase getData() {
  return data;
 }
 public long getExpire() {
  return expire;
 }
 @Override
 public boolean equals(Object obj) {
  if (obj instanceof DelayTask) {
   return this.data.getIdentifier().equals(((DelayTask) obj).getData().getIdentifier());
  }
  return false;
 }
 @Override
 public String toString() {
  return "{" + "data:" + data.toString() + "," + "expire:" + new Date(expire) + "}";
 }
 @Override
 public long getDelay(TimeUnit unit) {
  return unit.convert(this.expire - System.currentTimeMillis(), unit);
 }
 @Override
 public int compareTo(Delayed o) {
  long delta = getDelay(TimeUnit.NANOSECONDS) - o.getDelay(TimeUnit.NANOSECONDS);
  return (int) delta;
 }
}

import com.alibaba.fastjson.JSON;
public class TaskBase {
 private String identifier;
 public TaskBase(String identifier) {
  this.identifier = identifier;
 }
 public String getIdentifier() {
  return identifier;
 }
 public void setIdentifier(String identifier) {
  this.identifier = identifier;
 }
 @Override
 public String toString() {
  return JSON.toJSONString(this);
 }
}

import com.alibaba.fastjson.JSON;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.CommandLineRunner;
import org.springframework.stereotype.Component;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.concurrent.DelayQueue;
import java.util.concurrent.Executors;
@Component
public class DelayQueueManager implements CommandLineRunner {
 private final Logger logger = LoggerFactory.getLogger(DelayQueueManager.class);
 private DelayQueue<DelayTask> delayQueue = new DelayQueue<>();
 /**
  * 加入到延时队列中
  * @param task
  */
 public void put(DelayTask task) {
  logger.info("加入延时任务：{}", task);
  delayQueue.put(task);
 }
 /**
  * 取消延时任务
  * @param task
  * @return
  */
 public boolean remove(DelayTask task) {
  logger.info("取消延时任务：{}", task);
  return delayQueue.remove(task);
 }
 /**
  * 取消延时任务
  * @param taskid
  * @return
  */
 public boolean remove(String taskid) {
  return remove(new DelayTask(new TaskBase(taskid), 0));
 }
 @Override
 public void run(String... args) throws Exception {
  logger.info("初始化延时队列");
  Executors.newSingleThreadExecutor().execute(new Thread(this::excuteThread));
 }
 /**
  * 延时任务执行线程
  */
 private void excuteThread() {
  while (true) {
   try {
    DelayTask task = delayQueue.take();
    processTask(task);
   } catch (InterruptedException e) {
    break;
   }
  }
 }
 /**
  * 内部执行延时任务
  * @param task
  */
 private void processTask(DelayTask task) {
  logger.info("执行延时任务：{}", task);
  //根据task中的data自定义数据来处理相关逻辑，例 if (task.getData() instanceof XXX) {}
 }
}