pom.xml

    <dependencies>
        <dependency>
            <groupId>org.redisson</groupId>
            <artifactId>redisson</artifactId>
            <version>3.11.1</version>
        </dependency>
    </dependencies>

Car.java

package org.example;

import java.io.Serializable;

public class Car implements Serializable {
    private static final long serialVersionUID = -1L;
    private double price;
    private String colour;

    public Car(double price, String colour) {
        this.price = price;
        this.colour = colour;
    }

    public double getPrice() {
        return price;
    }

    public void setPrice(double price) {
        this.price = price;
    }

    public String getColour() {
        return colour;
    }

    public void setColour(String colour) {
        this.colour = colour;
    }

    @Override
    public String toString() {
        return colour + "car costs $" + price;
    }
}

Client.java

package org.example;

import org.redisson.Redisson;
import org.redisson.api.RTopic;
import org.redisson.api.RedissonClient;
import org.redisson.api.listener.MessageListener;
import org.redisson.codec.SerializationCodec;
import org.redisson.config.Config;

public class Client {
    public static void main(String[] args) {
        RedissonClient redisson = null;
        try{
            Config config = new Config();
            config.useSingleServer().setAddress("redis://127.0.0.1:6379");

            redisson = Redisson.create(config);

            RTopic topic = redisson.getTopic("dw",new SerializationCodec());
            topic.addListener(Car.class, new MessageListener<Car>() {
                @Override
                public void onMessage(CharSequence charSequence, Car car) {
                    System.out.println("onMessage:"+charSequence+"; Thread: "+Thread.currentThread().toString());
                    System.out.println(car.getColour()+" price : "+car.getPrice());
                }
            });


        }
        catch (Exception ex){
            System.out.println(ex.getMessage());
        }
        finally {

        }
    }
}

/*
onMessage:dw; Thread: Thread[redisson-3-12,5,main]
white price : 120000.0
 */

Server.java

package org.example;

import org.redisson.Redisson;
import org.redisson.api.RTopic;
import org.redisson.api.RedissonClient;
import org.redisson.codec.SerializationCodec;
import org.redisson.config.Config;

import java.util.concurrent.TimeUnit;

public class Server {
    public static void main(String[] args) {
        RedissonClient redisson = null;
        try{
            Config config = new Config();
            config.useSingleServer().setAddress("redis://127.0.0.1:6379");

            redisson = Redisson.create(config);

            RTopic topic1 = redisson.getTopic("dw", new SerializationCodec());

            while (true){
                topic1.publish(new Car(120000,"white"));
                TimeUnit.SECONDS.sleep(1);
            }
        }
        catch (Exception ex){
            System.out.println(ex.getMessage());
        }
        finally {
            redisson.shutdown();
        }
    }
}

总结：

1.redisson支持多个订阅者，1对多的发布。

2.主题相当于serverId，这样子，每个RTopic既是订阅者，又是发布者，因此可以充当MQ的功能用于服务之间的通信。

----------------20220326----------

redis还是以缓存为主。

当然了可以充当轻量级的进程间通信的工具，比如：这里的java类热加载，不经常发生，就可以使用这个轻量级的redisson实现。

还可以充当轻量级的服务发现，这样子让依赖的中间件更少一点。