2021-05-13-md1

本文介绍注解方式配置dubbo的例子。

服务提供Provider

1. 定义接口Animal和实现类Cat

Animal:

public interface Animal {/*** 描述: 返回动物的叫声*/String sound();
}

Cat:

package com.yt.provider;import com.alibaba.dubbo.config.annotation.Service;@Service(timeout = 5000)
public class Cat implements Animal {public String sound() {return "喵";}
}

@Service: 注解配置，服务提供者的service

2. Provider配置类

package com.yt.provider;import com.alibaba.dubbo.config.ApplicationConfig;
import com.alibaba.dubbo.config.ProtocolConfig;
import com.alibaba.dubbo.config.ProviderConfig;
import com.alibaba.dubbo.config.RegistryConfig;
import com.alibaba.dubbo.config.spring.context.annotation.EnableDubbo;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;/*** @author: yt* @date: 2021/5/13  21:40* @description:*/
@Configuration
@EnableDubbo(scanBasePackages = "com.yt.provider")
public class ProviderConfiguration {/*** dubbo应用配置*/@Beanpublic ApplicationConfig applicationConfig() {ApplicationConfig applicationConfig = new ApplicationConfig();applicationConfig.setName("myApp");applicationConfig.setOwner("yt");return applicationConfig;}/*** 配置服务提供者*/@Beanpublic ProviderConfig providerConfig() {ProviderConfig providerConfig = new ProviderConfig();providerConfig.setTimeout(1000);return providerConfig;}/*** 注册中心配置 zookeeper*/@Beanpublic RegistryConfig registryConfig() {RegistryConfig registryConfig = new RegistryConfig();registryConfig.setProtocol("zookeeper");registryConfig.setAddress("localhost:2181");registryConfig.setCheck(false);return registryConfig;}/*** 协议配置 dubbo:20880*/@Beanpublic ProtocolConfig protocolConfig() {ProtocolConfig protocolConfig = new ProtocolConfig();protocolConfig.setName("dubbo");protocolConfig.setPort(20880);return protocolConfig;}
}

@Configuration: 注解标明配置类，@EnableDubbo 指定扫描的包路径。

配置的内容主要有：

• 应用配置 ：类似 <dubbo:application 标签
• 服务提供者配置：类似<dubbo:provider‘标签
• 注册中心配置：类似<dubbo:registry 标签
• 协议配置：类似 <dubbo:protocol 标签

3. 启动服务

public class Provider {public static void main(String[] args) throws IOException {AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(ProviderConfiguration.class);context.start();System.in.read();}
}

指定配置类之后，就可以启动。

服务消费Consumer

1. 创建服务消费service

package com.yt.consumer;import com.alibaba.dubbo.config.annotation.Reference;
import com.yt.provider.Animal;
import org.springframework.stereotype.Component;@Component
public class ConsumerService {@Referenceprivate Animal animal;public String sound() {return animal.sound();}
}

新建一个service类，加上@Component注解，将对象交给spring管理，之后加上@Reference注解注入Animal接口。

2. 服务消费配置类

package com.yt.consumer;import com.alibaba.dubbo.config.ApplicationConfig;
import com.alibaba.dubbo.config.ConsumerConfig;
import com.alibaba.dubbo.config.RegistryConfig;
import com.alibaba.dubbo.config.spring.context.annotation.EnableDubbo;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.stereotype.Component;/*** @author: yt* @date: 2021/5/13  21:52* @description:*/
@Configuration
@EnableDubbo(scanBasePackages = "com.yt.consumer")
@ComponentScan(value = {"com.yt.consumer"})
public class ConsumerConfiguration {/*** 应用配置*/@Beanpublic ApplicationConfig applicationConfig() {ApplicationConfig applicationConfig = new ApplicationConfig();applicationConfig.setName("myApp");applicationConfig.setOwner("yt");return applicationConfig;}/*** 消费者配置*/@Beanpublic ConsumerConfig consumerConfig() {ConsumerConfig consumerConfig = new ConsumerConfig();consumerConfig.setTimeout(3000);return consumerConfig;}/*** 注册中心配置*/@Beanpublic RegistryConfig registryConfig() {RegistryConfig registryConfig = new RegistryConfig();registryConfig.setProtocol("zookeeper");registryConfig.setAddress("localhost:2181");return registryConfig;}
}

跟服务提供者的配置类似。

@ComponentScan(value = {"com.yt.consumer"}) 指定要扫描component的包路径，扫描ConsumerService。

3. 启动服务

public class Consumer {public static void main(String[] args) {AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(ConsumerConfiguration.class);context.start();// 从spring容器中取得beanConsumerService consumerService = context.getBean(ConsumerService.class);System.out.println("consumer:" + consumerService.sound());}
}

服务成功启动，并输出结果(记得启动zookeeper)：

consumer:喵