[Java知识库]Spring Boot StringRedisTemplate 发布订阅

一、引入依赖

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-pool2</artifactId>
        </dependency>

二、配置

spring.redis.host=127.0.0.1
spring.redis.port=6379
spring.redis.password=123456
spring.redis.database=0
# 连接超时时间（毫秒）
spring.redis.timeout=10000
# 连接池最大阻塞等待时间（使用负值表示没有限制） 默认 -1
spring.redis.lettuce.pool.max-wait=300
# 连接池中的最大空闲连接
spring.redis.lettuce.pool.max-idle=10
# 连接池中的最小空闲连接
spring.redis.lettuce.pool.min-idle=5
# 连接池最大连接数（使用负值表示没有限制） 默认 8
spring.redis.lettuce.pool.max-active=100

三、监听代码

package com.china.system.service;

import org.springframework.data.redis.connection.MessageListener;

/**
 * Redis 订阅
 *
 * @author songjy
 */
public interface RedisSubscribeService extends MessageListener {
}

实现类

package com.china.system.service.impl;

import com.china.system.service.RedisSubscribeService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.data.redis.connection.Message;
import org.springframework.data.redis.listener.adapter.MessageListenerAdapter;
import org.springframework.lang.Nullable;
import org.springframework.stereotype.Component;

import java.util.Objects;

/**
 * redis 订阅：https://docs.spring.io/spring-data/data-redis/docs/current/reference/html/#pubsub
 *
 * @author songjy
 */
@Component
@Slf4j
public class RedisSubscribeServiceImpl extends MessageListenerAdapter implements RedisSubscribeService {

    @Override
    public void onMessage(@Nullable Message message, byte[] bytes) {

        if (Objects.isNull(message)) {
            log.error("消息为空");
            return;
        }

        String channel = new String(message.getChannel());
        String body = new String(message.getBody());
        log.info("订阅频道：{}{}消息：{}", channel, System.lineSeparator(), body);
    }
}

四、监听配置

package com.china.system.config;

import com.china.system.service.RedisSubscribeService;
import com.google.common.collect.Lists;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.listener.ChannelTopic;
import org.springframework.data.redis.listener.RedisMessageListenerContainer;

/**
 * @author songjy
 */
@Configuration
public class RedisConfig {

    @Bean
    public RedisMessageListenerContainer redisMessageListenerContainer(RedisConnectionFactory connectionFactory,
                                                                       RedisSubscribeService redisSubscribeService) {
        RedisMessageListenerContainer redisMessageListenerContainer = new RedisMessageListenerContainer();
        redisMessageListenerContainer.setConnectionFactory(connectionFactory);
        redisMessageListenerContainer.addMessageListener(redisSubscribeService, Lists.newArrayList(
                ChannelTopic.of("song"),
                ChannelTopic.of("jian"),
                ChannelTopic.of("yong")
        ));
        return redisMessageListenerContainer;
    }
}

五、消息发布

package com.china.system.service;

/**
 * Redis 发布
 *
 * @author songjy
 */
public interface RedisPublishService {
    /**
     * 发布消息
     *
     * @param channel 频道
     * @param message 消息
     */
    void sendMessage(String channel, String message);
}

实现类

package com.china.system.service.impl;

import com.china.system.service.RedisPublishService;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Component;

/**
 * @author songjy
 */
@Component
@Slf4j
public class RedisPublishServiceImpl implements RedisPublishService {
    private StringRedisTemplate stringRedisTemplate;

    @Autowired
    public void setStringRedisTemplate(StringRedisTemplate stringRedisTemplate) {
        this.stringRedisTemplate = stringRedisTemplate;
    }

    @Override
    public void sendMessage(String channel, String message) {
        if (StringUtils.isBlank(message)) {
            return;
        }
        stringRedisTemplate.convertAndSend(channel, message);
        log.info("频道【{},{}】消息已发布", channel, message);
    }
}

六、消息发布订阅单元测试

package com.china.system.service.impl;

import com.china.system.RedisDemoApplication;
import com.china.system.service.RedisPublishService;
import lombok.Data;
import lombok.extern.slf4j.Slf4j;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.ActiveProfiles;
import org.springframework.test.context.junit4.SpringRunner;
import org.springframework.transaction.annotation.Transactional;

import java.util.concurrent.TimeUnit;

@SpringBootTest(classes = {RedisDemoApplication.class})
@RunWith(SpringRunner.class)
@Transactional
@Slf4j
@Data
@ActiveProfiles("beta")
public class RedisPublishServiceImplTests {
    private RedisPublishService redisPublishService;

    @Autowired
    public void setRedisPublishService(RedisPublishService redisPublishService) {
        this.redisPublishService = redisPublishService;
    }

    @Test
    public void sendMessageTest() throws InterruptedException {
        redisPublishService.sendMessage("song", "song" + System.currentTimeMillis());
        redisPublishService.sendMessage("jian", "jian" + System.currentTimeMillis());
        redisPublishService.sendMessage("yong", "yong" + System.currentTimeMillis());
        log.info("消息发布完毕");
        TimeUnit.SECONDS.sleep(5L);
    }
}