Dubbo（三）之Spring zookeeper集成

Love The Way You Lie 2022-10-25 12:58 58阅读 0赞

转载自  [Dubbo快速开始][Dubbo]

Dubbo 采用全 Spring 配置方式，透明化接入应用，对应用没有任何 API 侵入，只需用 Spring 加载 Dubbo 的配置即可，Dubbo 基于 [Spring 的 Schema 扩展][Spring _ Schema] 进行加载。

如果不想使用 Spring 配置，可以通过 [API 的方式][API] 进行调用。

## 服务提供者 ##

完整安装步骤，请参见：[示例提供者安装][Link 1]

安装：

git clone https://github.com/apache/dubbo.git
    cd dubbo/dubbo-demo/dubbo-demo-xml
    运行 dubbo-demo-xml-provider中的org.apache.dubbo.demo.provider.Application
    如果使用Intellij Idea 请加上-Djava.net.preferIPv4Stack=true

配置：

resources/spring/dubbo-provider.xml
    修改其中的dubbo:registry，替换成真实的注册中心地址，推荐使用zookeeper，如：
    <dubbo:registry address="zookeeper://127.0.0.1:2181"/>

### 定义服务接口 ###

DemoService.java [1][]：

package org.apache.dubbo.demo;
    
    public interface DemoService {
        String sayHello(String name);
    }

### 在服务提供方实现接口 ###

DemoServiceImpl.java [2][]：

package org.apache.dubbo.demo.provider;
     
    import org.apache.dubbo.demo.DemoService;
     
    public class DemoServiceImpl implements DemoService {
        public String sayHello(String name) {
            return "Hello " + name;
        }
    }

### 用 Spring 配置声明暴露服务 ###

provider.xml：

<?xml version="1.0" encoding="UTF-8"?>
    <beans xmlns="http://www.springframework.org/schema/beans"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xmlns:dubbo="http://dubbo.apache.org/schema/dubbo"
        xsi:schemaLocation="http://www.springframework.org/schema/beans        http://www.springframework.org/schema/beans/spring-beans-4.3.xsd        http://dubbo.apache.org/schema/dubbo        http://dubbo.apache.org/schema/dubbo/dubbo.xsd">
     
        
        <dubbo:application name="hello-world-app"  />
     
        
        <dubbo:registry address="multicast://224.5.6.7:1234" />
     
        
        <dubbo:protocol name="dubbo" port="20880" />
     
        
        <dubbo:service interface="org.apache.dubbo.demo.DemoService" ref="demoService" />
     
        
        <bean id="demoService" class="org.apache.dubbo.demo.provider.DemoServiceImpl" />
    </beans>

### 加载 Spring 配置 ###

Provider.java：

import org.springframework.context.support.ClassPathXmlApplicationContext;
     
    public class Provider {
        public static void main(String[] args) throws Exception {
            ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(new String[]{"META-INF/spring/dubbo-demo-provider.xml"});
            context.start();
            System.in.read(); // 按任意键退出
        }
    }

## 服务消费者 ##

完整安装步骤，请参见：[示例消费者安装][Link 2]

### 通过 Spring 配置引用远程服务 ###

consumer.xml：

<?xml version="1.0" encoding="UTF-8"?>
    <beans xmlns="http://www.springframework.org/schema/beans"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xmlns:dubbo="http://dubbo.apache.org/schema/dubbo"
        xsi:schemaLocation="http://www.springframework.org/schema/beans        http://www.springframework.org/schema/beans/spring-beans-4.3.xsd        http://dubbo.apache.org/schema/dubbo        http://dubbo.apache.org/schema/dubbo/dubbo.xsd">
     
        
        <dubbo:application name="consumer-of-helloworld-app"  />
     
        
        <dubbo:registry address="multicast://224.5.6.7:1234" />
     
        
        <dubbo:reference id="demoService" interface="org.apache.dubbo.demo.DemoService" />
    </beans>

### 加载Spring配置，并调用远程服务 ###

Consumer.java [3][]：

import org.springframework.context.support.ClassPathXmlApplicationContext;
    import org.apache.dubbo.demo.DemoService;
     
    public class Consumer {
        public static void main(String[] args) throws Exception {
           ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(new String[] {"META-INF/spring/dubbo-demo-consumer.xml"});
            context.start();
            DemoService demoService = (DemoService)context.getBean("demoService"); // 获取远程服务代理
            String hello = demoService.sayHello("world"); // 执行远程方法
            System.out.println( hello ); // 显示调用结果
        }
    }

--------------------

1.  该接口需单独打包，在服务提供方和消费方共享 [↩︎][Link 3]
2.  对服务消费方隐藏实现 [↩︎][Link 4]
3.  也可以使用 IoC 注入 [↩︎][Link 5]

[Dubbo]: https://dubbo.apache.org/zh/docs/v2.7/user/quick-start/
[Spring _ Schema]: https://docs.spring.io/spring/docs/4.2.x/spring-framework-reference/html/xsd-configuration.html
[API]: https://dubbo.apache.org/zh/docs/v2.7/user/configuration/api
[Link 1]: https://dubbo.apache.org/zh/docs/v2.7/admin/install/provider-demo
[1]: https://dubbo.apache.org/zh/docs/v2.7/user/quick-start/#fn:1
[2]: https://dubbo.apache.org/zh/docs/v2.7/user/quick-start/#fn:2
[Link 2]: https://dubbo.apache.org/zh/docs/v2.7/admin/install/consumer-demo
[3]: https://dubbo.apache.org/zh/docs/v2.7/user/quick-start/#fn:3
[Link 3]: https://dubbo.apache.org/zh/docs/v2.7/user/quick-start/#fnref:1
[Link 4]: https://dubbo.apache.org/zh/docs/v2.7/user/quick-start/#fnref:2
[Link 5]: https://dubbo.apache.org/zh/docs/v2.7/user/quick-start/#fnref:3