使用jedis实现Redis消息队列(MQ)的发布(publish)和消息监听(subscribe)

前言：

本文基于jedis 2.9.0.jar、commons-pool2-2.4.2.jar以及json-20160810.jar

其中jedis连接池需要依赖commons-pool2包，json包用于对象实例和json字符串的相互转换

1、jedis的消息队列方法简述

1.1、发布消息方法

（其中，channel是对应消息通道，message是对应消息体）

jedis.publish(channel, message);

1.2、监听消息方法

（其中，jedisPubSub用于处理监听到的消息，channels是对应的通道）

jedis.subscribe(jedisPubSub, channels);

2、发布消息

/**
* 从jedis连接池获取jedis操作实例
* @return
*/
public static Jedis getJedis() {
return RedisPoolManager.getJedis();
}

/**
* 推入消息到redis消息通道
*
* @param String
* channel
* @param String
* message
*/
public static void publish(String channel, String message) {
Jedis jedis = null;
try {
jedis = getJedis();
jedis.publish(channel, message);
} finally {
jedis.close();
}
}

/**
* 推入消息到redis消息通道
*
* @param byte[]
* channel
* @param byte[]
* message
*/
public void publish(byte[] channel, byte[] message) {
Jedis jedis = null;
try {
jedis = getJedis();
jedis.publish(channel, message);
} finally {
jedis.close();
}

}

3、监听消息

3.1、监听消息主体方法

/**
* 监听消息通道
* @param jedisPubSub - 监听任务
* @param channels - 要监听的消息通道
*/
public static void subscribe(BinaryJedisPubSub jedisPubSub, byte[]... channels) {
Jedis jedis = null;
try {
jedis = getJedis();
jedis.subscribe(jedisPubSub, channels);
} finally {
jedis.close();
}
}

/**
* 监听消息通道
* @param jedisPubSub - 监听任务
* @param channels - 要监听的消息通道
*/
public static void subscribe(JedisPubSub jedisPubSub, String... channels) {
Jedis jedis = null;
try {
jedis = getJedis();
jedis.subscribe(jedisPubSub, channels);
} finally {
jedis.close();
}
}

3.2、处理监听到的消息任务

class Tasker implements Runnable {
private String[] channel = null;//监听的消息通道
private JedisPubSub jedisPubSub = null;//消息处理任务

public Tasker(JedisPubSub jedisPubSub, String ...channel) {
this.jedisPubSub = jedisPubSub;
this.channel = channel;
}

@Override
public void run() {
// 监听channel通道的消息
RedisMQ.subscribe(jedisPubSub, channel);
}

}

3.3、处理监听到的消息主体类实现

package cn.eguid.livePushServer.redisManager;

import java.util.Map;

import org.json.JSONObject;

import cc.eguid.livepush.PushManager;
import redis.clients.jedis.JedisPubSub;

public class RedisMQHandler extends JedisPubSub{
PushManager pushManager = null;

public RedisMQHandler(PushManager pushManager) {
super();
this.pushManager = pushManager;
}

@Override
// 接收到消息后进行分发执行
public void onMessage(String channel, String message) {
JSONObject jsonObj = new JSONObject(message);
System.out.println(channel+","+message);
if ("push".equals(channel)) {
Map<String,Object> map=jsonObj.toMap();
System.out.println("接收到一条推流消息，准备推流："+map);
//			String appName=pushManager.push(map);
//推流完成后还需要发布一个成功消息到返回队列

} else if ("close".equals(channel)) {
String appName=jsonObj.getString("appName");
System.out.println("接收到一条关闭消息，准备关闭应用："+appName);
//			pushManager.closePush(appName);
}
}
}

4、测试消息队列发布和监听

public static void main(String[] args) throws InterruptedException {

PushManager pushManager= new PushManagerImpl();
Thread t1 = new Thread(new Tasker(new RedisMQHandler (pushManager), "push"));
Thread t2 = new Thread(new Tasker(new RedisMQHandler (pushManager), "close"));
t1.start();
t2.start();

LivePushEntity livePushInfo=new LivePushEntity();
livePushInfo.setAppName("test1");
JSONObject json=new JSONObject(livePushInfo);
publish("push",json.toString());
publish("close", json.toString());
Thread.sleep(2000);
publish("push", json.toString());
publish("close",json.toString());
Thread.sleep(2000);
publish("push", json.toString());
publish("close",json.toString());

}