Implementation description: Implementation of DelayQueue delay queue design based on Redis
Source code address: RedisDelayQueue
RedisDelayQueue access instructions
1. Introduce pom
Package and push the redis-delay-queue-core module in the project to your company's central warehouse, and then introduce the pom dependency
<dependency>
<artifactId>redis-delay-queue-core</artifactId>
<groupId>com.shirc</groupId>
<version>0.0.1-SNAPSHOT</version>
</dependency>
2. RedisDelayQueue is managed by Spring
/**
* @Description 引入 redisdelayqueue
* @Author shirenchuang
* @Date 2019/8/6 5:58 PM
**/
@Component
public class DelayConfig {
@Autowired
private RedisTemplate redisTemplate;
@Bean
public RedisDelayQueueContext getRdctx(){
/**传入redisTemplate实例, 第二个参数为项目名 projectName ;不同项目需要设置不一样**/
RedisDelayQueueContext context = new RedisDelayQueueContext(redisTemplate,"dq_demo");
return context;
}
/**加了这个 可以在其他地方直接 @Autowire RedisDelayQueue 使用了**/
@Bean
public RedisDelayQueue getRedisOperation(RedisDelayQueueContext context){
return context.getRedisDelayQueue();
}
}
3. Register Topic tasks
/**
* @Description 注册延迟队列 Demo
* @Author shirenchuang
* @Date 2019/8/8 10:07 AM
**/
@Service
public class DelayQueueDemoJob extends AbstractTopicRegister<DemoArgs> {
@Override
public String getTopic() {
return DelayJobTopicEnums.DEMO_TEST.getTopic();
}
@Override
public void execute(DemoArgs demoArgs) {
// 延迟任务回调接口
//id : 这个Topic下的唯一值
String id = demoArgs.getId();
//重试次数; 如果回调接口超时失败, 调用失败,会自动重试2次; 这个代表重试次数
int retryCount = demoArgs.getRetryCount();
//DemoArgs 是要继承 Args的; 如果没有自己需要定义的回调参数; 泛型那里直接写 Args就行了
System.out.println(demoArgs.getTest());
}
/******下面方法可选重写 根据消费情况可以自行调节 超时时间,线程池大小等等******/
/**
* 重试2次仍然失败; 通知接口; 可以在这个接口写自己的通知逻辑; 比如发送邮件或者钉钉消息
* @param demoArgs
*/
@Override
public void retryOutTimes(DemoArgs demoArgs) {
super.retryOutTimes(demoArgs);
}
/**
* 设置核心线程池数量 默认2
* @return
*/
@Override
public int getCorePoolSize() {
return super.getCorePoolSize();
}
/**
* 设置线程池最大线程数量 默认
* @return
*/
@Override
public int getMaxPoolSize() {
return super.getMaxPoolSize();
}
/**
* 可以重写 回调方法的超时时间 默认回调接口超时时间 6秒
* @return
*/
@Override
public int getMethodTimeout() {
return super.getMethodTimeout();
}
}
DemoArgs above
/**
* @Description 回调参数Demo
* @Author shirenchuang
* @Date 2019/8/8 10:07 AM
**/
public class DemoArgs extends Args {
private String test;
public String getTest() {
return test;
}
public void setTest(String test) {
this.test = test;
}
}
If there is no callback attribute defined by yourself, or you only need an id, then just pass Args in the generic type, which will return the id;
Below are the defined Args
public class Args implements Serializable {
private static final long serialVersionUID = 66666l;
/**唯一键 不能为空**/
private String id;
/**
* 已经重试的次数:
* 重试机制: 默认重试2次; 总共最多执行3次
* 添加任务的时候可以设置为<0 的值;则表示不希望重试;
* 回调接口自己做好幂等
***/
private int retryCount;
/**
* 重入次数:
* 这里标记的是当前Job某些异常情况导致并没有真正消费到,然后重新放入待消费池的次数;
* 比如: BLPOP出来了之后,在去获取Job的时候redis超时了,导致没有正常消费掉;
* 重入次数最大 3次; 避免某些不可控因素出现,超过3次则丢弃
*/
private int reentry;
public Args() {
}
public Args(String id) {
this.id = id;
}
public Args(String id, int retryCount) {
this.id = id;
this.retryCount = retryCount;
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public int getRetryCount() {
return retryCount;
}
public void setRetryCount(int retryCount) {
this.retryCount = retryCount;
}
public int getReentry() {
return reentry;
}
public void setReentry(int reentry) {
this.reentry = reentry;
}
@Override
public String toString() {
return "Args{" +
"id='" + id + '\'' +
", retryCount=" + retryCount +
", reentry=" + reentry +
'}';
}
4. It is recommended to create a new enumeration class of Topic
Because the topic of the new task must be consistent with the topic of the registration place and the topic of deletion, it is recommended to use enumeration.
/**
* @Description 所有延迟任务的Topic
* @Author shirenchuang
**/
public enum DelayJobTopicEnums {
DEMO_TEST("DEMO_TEST","测试"),
;
private String topic;
private String desc;
DelayJobTopicEnums(String topic, String desc) {
this.topic = topic;
this.desc = desc;
}
public String getTopic() {
return topic;
}
public String getDesc() {
return desc;
}
}
5. How to add a delayed task and delete a delayed task
/**
* @Description 新增删除延迟任务
* @Author shirenchuang
* @Date 2019/8/8 10:29 AM
**/
@Component
public class DelayQueueUseDemo {
@Autowired
RedisDelayQueue redisDelayQueue;
private void addDelayQueue(){
//do something
//新增一个延迟任务
DemoArgs demoArgs = new DemoArgs();
demoArgs.setId(UUID.randomUUID().toString());
//设置-1 表示我不想要重试
demoArgs.setRetryCount(-1);
demoArgs.setTest("我是个Test");
//异步新增一个 一分钟之后执行的延时任务
redisDelayQueue.addAsync(demoArgs,DelayJobTopicEnums.DEMO_TEST.getTopic(),60000);
//也可以同步新增延迟任务
redisDelayQueue.add(demoArgs,60000,DelayJobTopicEnums.DEMO_TEST.getTopic(),RunTypeEnum.SYNC);
//也可以指定某个时间点执行
redisDelayQueue.add(demoArgs,DelayJobTopicEnums.DEMO_TEST.getTopic(),System.currentTimeMillis()+60000,RunTypeEnum.ASYNC);
/**PS:如果同一个ID添加了多次,以最新添加的为准,会覆盖之前的**/
/**如果自己没有需要回调的参数 直接用Args**/
redisDelayQueue.addAsync(new Args(id),DelayJobTopicEnums.DEMO_TEST.getTopic(),60000);
}
//删除一个之前添加的延迟任务
private void delDelayQueue(String id){
//异步删除
redisDelayQueue.deleteAsync(DelayJobTopicEnums.DEMO_TEST.getTopic(),id);
//同步删除
redisDelayQueue.delete(DelayJobTopicEnums.DEMO_TEST.getTopic(),id,RunTypeEnum.SYNC);
}
}
6. Redis task view
