启动RocketMQ
-
启动nameserver
-
修改broker配置参数，新增
messageDelayLevel=1s 2s 4s 8s 16s 32s 64s 128s 256s 512s 1024s 2048s 4096s 8192s 16384s 32768s 65536s 131072s -
org.apache.rocketmq.common.message.MessageConst新增常量
public static final String PROPERTY_MSG_REMAIN_DELAY = "MSG_REMAIN_DELAY_SERVER";
- org.apache.rocketmq.store.util包下新增工具类
package org.apache.rocketmq.store.util;
/**
* 任意延时工具类
*
* @author zby
*
*/
public class ArbitrarilyDelayUtil {
/**
* 延时时间
*/
private static final long[] delayArray = new long[] { 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192,
16384, 32768, 65536, 131072 };
private ArbitrarilyDelayUtil() {
}
/**
* 根据延时等级获取延时时间
*
* @param delayLevel 延时等级
* @return 延时时间
*/
public static long getDelayTimeFromDelayLevel(int delayLevel) {
validDelayLevel(delayLevel);
if (delayLevel == 0) {
return 0;
}
return delayArray[delayLevel - 1];
}
/**
* 根据延时时间获取最近的延时等级
*
* @param delayTime
* @return
*/
public static int getLatestDelayLevelFromDelayTime(long delayTime) {
validDelayTime(delayTime);
if (delayTime == 0) {
return 0;
}
for (int i = 0; i < delayArray.length - 1; i++) {
if (delayTime >= delayArray[i] && delayTime < delayArray[i + 1]) {
return i + 1;
}
}
return delayArray.length;
}
/**
* 校验延时时间
*/
private static void validDelayTime(long delayTime) {
if (delayTime < 0) {
throw new IllegalArgumentException("Not supported delay time:" + delayTime);
}
}
/**
* 校验延时等级
*/
private static void validDelayLevel(int delayLevel) {
if (delayLevel < 0 || delayLevel > delayArray.length) {
throw new IllegalArgumentException("Not supported delay level:" + delayLevel);
}
}
}
- org.apache.rocketmq.store.CommitLog类新增代码，根据新增代码前的代码找到新增的位置
if (tranType == MessageSysFlag.TRANSACTION_NOT_TYPE || tranType == MessageSysFlag.TRANSACTION_COMMIT_TYPE) {
// Delay Delivery
if (msg.getDelayTimeLevel() > 0) {
省略.....
}
<!-- 新增代码开始-->
if (msg.getUserProperty(MessageConst.PROPERTY_MSG_REMAIN_DELAY) != null
&& Long.parseLong(msg.getUserProperty(MessageConst.PROPERTY_MSG_REMAIN_DELAY)) > 0) {
long remainDelay = Long.parseLong(msg.getUserProperty(MessageConst.PROPERTY_MSG_REMAIN_DELAY));
int delayTimeLevel = ArbitrarilyDelayUtil.getLatestDelayLevelFromDelayTime(remainDelay);
msg.setDelayTimeLevel(delayTimeLevel);
msg.putUserProperty(MessageConst.PROPERTY_MSG_REMAIN_DELAY,
Long.toString(remainDelay - ArbitrarilyDelayUtil.getDelayTimeFromDelayLevel(delayTimeLevel)));
topic = ScheduleMessageService.SCHEDULE_TOPIC;
queueId = ScheduleMessageService.delayLevel2QueueId(msg.getDelayTimeLevel());
// Backup real topic, queueId
MessageAccessor.putProperty(msg, MessageConst.PROPERTY_REAL_TOPIC, msg.getTopic());
MessageAccessor.putProperty(msg, MessageConst.PROPERTY_REAL_QUEUE_ID, String.valueOf(msg.getQueueId()));
msg.setPropertiesString(MessageDecoder.messageProperties2String(msg.getProperties()));
msg.setTopic(topic);
msg.setQueueId(queueId);
}
<!-- 新增代码结束-->
}
- 启动broker
公共代码
延时等级转换工具类
package com.zby.server;
import java.util.concurrent.TimeUnit;
import org.apache.rocketmq.common.message.Message;
/**
* 消息延时工具类
*
* @author mac
*
*/
public class DelayUtil {
public static final String PROPERTY_MSG_REMAIN_DELAY = "MSG_REMAIN_DELAY_SERVER";
private DelayUtil() {
}
/**
* 消息任意延时发送
*
* @param msg 消息
* @param delayTime 延迟时间
* @param timeUnit 延迟时间单位
*/
public static void delayMsg(Message msg, long delayTime, TimeUnit timeUnit) {
msg.putUserProperty(PROPERTY_MSG_REMAIN_DELAY, Long.toString(timeUnit.toSeconds(delayTime)));
}
}
生产者
生产者示例
package com.zby.server;
import java.nio.charset.StandardCharsets;
import java.util.Date;
import java.util.concurrent.TimeUnit;
import org.apache.rocketmq.client.producer.DefaultMQProducer;
import org.apache.rocketmq.client.producer.SendResult;
import org.apache.rocketmq.common.message.Message;
public class Producer {
public static void main(String[] args) throws Exception {
DefaultMQProducer producer = new DefaultMQProducer("please_rename_unique_group_name");
producer.setNamesrvAddr("localhost:9876");
producer.start();
Message msg = new Message("TopicTest", ("消息发送时间 :" + new Date()).getBytes(StandardCharsets.UTF_8));
DelayUtil.delayMsg(msg, 27, TimeUnit.MINUTES);
SendResult sendResult = producer.send(msg);
System.out.println("消息发送结果:" + sendResult.getSendStatus());
producer.shutdown();
}
}
消费者
消费者示例
package com.zby.server;
import java.io.UnsupportedEncodingException;
import java.util.Date;
import java.util.List;
import org.apache.rocketmq.client.consumer.DefaultMQPushConsumer;
import org.apache.rocketmq.client.consumer.listener.ConsumeConcurrentlyContext;
import org.apache.rocketmq.client.consumer.listener.ConsumeConcurrentlyStatus;
import org.apache.rocketmq.client.consumer.listener.MessageListenerConcurrently;
import org.apache.rocketmq.common.consumer.ConsumeFromWhere;
import org.apache.rocketmq.common.message.MessageExt;
import org.apache.rocketmq.remoting.common.RemotingHelper;
public class Consumer {
public static void main(String[] args) throws Exception {
DefaultMQPushConsumer consumer = new DefaultMQPushConsumer("please_rename_unique_group_name_4");
consumer.setNamesrvAddr("localhost:9876");
consumer.setConsumeFromWhere(ConsumeFromWhere.CONSUME_FROM_FIRST_OFFSET);
consumer.subscribe("TopicTest", "*");
consumer.registerMessageListener(new MessageListenerConcurrently() {
@Override
public ConsumeConcurrentlyStatus consumeMessage(List<MessageExt> msgs, ConsumeConcurrentlyContext context) {
try {
System.out.printf("now:%s,%s Receive New Messages: %s %n", new Date(),
Thread.currentThread().getName(),
new String(msgs.get(0).getBody(), RemotingHelper.DEFAULT_CHARSET));
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;
}
});
consumer.start();
System.out.printf("Consumer Started.%n");
}
}
启动测试
- 启动消费者
- 启动生产者
- 消费者输出结果
Consumer Started.
now:Wed Jul 22 12:42:45 CST 2020,ConsumeMessageThread_1 Receive New Messages: 消息发送时间 :Wed Jul 22 12:42:18 CST 2020
优点
- 客户端唯一需要的就是发送消息前调用DelayUtil.delayMsg(msg, 27, TimeUnit.MINUTES);
- 生产消费代码都是copy的quickstart的demo，可以看出侵入性很小
注意
- 改了延时等级，重试的延时间隔也会更改