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Spring Cloud Stream消息驱动之RocketMQ入门（一）

SpringCloudStream目前支持的中间件有RabbitMQ、Kafka，还有我最近在学习的RocketMQ,以下是我学习的笔记

学习Spring cloud Stream 可以先学习一下了解 Spring Messaging 和 Spring Integration，

先看看Spring Message 消息的模型

Messaging 对应的模型就包括一个消息体 Payload 和消息头 Header

Spring Cloud Stream消息驱动之RocketMQ入门（一）

消息通道 MessageChannel 用于接收消息，调用 send 方法可以将消息发送至该消息通道中，直接撸demo吧

pom.xml 依赖

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.2.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>cloud-stream-rocketmq-demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>cloud-stream-rocketmq-demo</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-stream</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-stream-binder-rocketmq</artifactId>
            <version>0.2.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Hoxton.SR1</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

@EnableBinding：该注解用来指定一个或多个定义了@Input或@Output注解的接口，以此实现对消息通道（Channel）的绑定

@StreamListener：该注解主要定义在方法上，作用是将被修饰的方法注册为消息中间件上数据流的事件监听器，注解中的属性值对应了监听的消息通道名

@Component
@EnableBinding(StreamInput.class)
@Slf4j
public class ReceiveClient {

    @StreamListener(StreamInput.input)
    public void receive01(String message){
        log.info("接收消息："+message);
    }


}

@Input注解绑定了一个名为input的通道

public interface StreamInput {

    String input = "input";

    @Input(StreamInput.input)
    SubscribableChannel input();
}

@Output注解绑定了一个名为Output的通道

public interface StreamInput {

    String input = "input";

    @Input(StreamInput.input)
    SubscribableChannel input();
}

测试一下

启动类加上刚刚添加的两个接口

@EnableBinding({StreamInput.class, StreamOutput.class})

@Autowired
    private StreamOutput streamOutput;

    @GetMapping("/send")
    public String send(){
        MessageBuilder builder = MessageBuilder.withPayload("测试消息".getBytes());
        streamOutput.output().send(builder.build());
        return "ok";
    }

不要忘记@EnableBinding注解绑定