Dubbo之旅--Consumer示例

      我们已经对提供者示例进行了详细的阐述,接下来的消费者相对而言比较简单.

     1 配置相关pom.xml信息,跟提供者类似,需要相关环境的java包应用.

<projectxmlns="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 http://maven.apache.org/xsd/maven-4.0.0.xsd">

    <parent>

       <artifactId>dubbo-demo</artifactId>

       <groupId>org.pactera.dubbo</groupId>

       <version>1.0-SNAPSHOT</version>

    </parent>

   <modelVersion>4.0.0</modelVersion>

   <groupId>org.pactera.dubbo</groupId>

   <artifactId>dubbo-demo-consumer</artifactId>

    <packaging>jar</packaging>

   <name>dubbo-demo-consumer</name>

   <url>http://maven.apache.org</url>

    <properties>

       <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>

    </properties>

    <dependencies>

        <dependency>

           <groupId>org.pactera.dubbo</groupId>

           <artifactId>dubbo-demo-api</artifactId>

           <version>1.0-SNAPSHOT</version>

        </dependency>

        <dependency>

           <groupId>org.pactera.dubbo</groupId>

           <artifactId>dubbo-expand-loadbalance</artifactId>

           <version>1.0-SNAPSHOT</version>

        </dependency>

        <dependency>

           <groupId>com.alibaba</groupId>

           <artifactId>dubbo</artifactId>

           <version>2.4.10</version>

        </dependency>

        <dependency>

           <groupId>com.101tec</groupId>

           <artifactId>zkclient</artifactId>

            <version>0.3</version>

        </dependency>

        <dependency>

           <groupId>junit</groupId>

           <artifactId>junit</artifactId>

           <version>3.8.1</version>

            <scope>test</scope>

        </dependency>

    </dependencies>

    </project>

2 消费者相关的配置文件如下:

/dubbo-demo/dubbo-demo-consumer/src/main/resources/dubbo-demo-consumer.xml

<?xmlversion="1.0" encoding="UTF-8"?>

<beansxmlns="http://www.springframework.org/schema/beans"

   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

   xmlns:dubbo="http://code.alibabatech.com/schema/dubbo"

   xsi:schemaLocation="http://www.springframework.org/schema/beans

        http://www.springframework.org/schema/beans/spring-beans.xsd

        http://code.alibabatech.com/schema/dubbo

        http://code.alibabatech.com/schema/dubbo/dubbo.xsd

        ">

    <!-- 消费方应用名，用于计算依赖关系，不是匹配条件，不要与提供方一样-->

    <dubbo:applicationname="consumer-of-helloworld-app" />

    <!-- 使用multicast广播注册中心暴露发现服务地址 -->

<!--     <dubbo:registryaddress="multicast://224.5.6.7:1234" /> -->

    <dubbo:registryprotocol="zookeeper" address="127.0.0.1:2181" />

    <dubbo:protocol name="dubbo"port="20884" />

<dubbo:monitorprotocol="registry"></dubbo:monitor>

    <!-- 生成远程服务代理，可以和本地bean一样使用demoService-->

    <dubbo:referenceid="demoService" interface="org.pactera.dubbo.DemoService"retries="0" timeout="30000" />

   </beans>

        这里跟提供者不一样的地方,在生成的远程服务代理,可以像调用本地的bean一样使用提供者服务demoService.很好的跟Spring融合在一起.

3  接下来我们需要模拟一个消费者的行为,此行为用来调用demoService服务,从而实现相关的功能,如下文件:

/dubbo-demo/dubbo-demo-consumer/src/main/java/org/pactera/dubbo/DemoServiceConsumer.java

packageorg.pactera.dubbo;

importcom.alibaba.dubbo.rpc.RpcContext;

importlombok.extern.slf4j.Slf4j;

importorg.pactera.dubbo.model.Count;

importorg.pactera.dubbo.thread.DemoServiceConsumerThread;

importorg.springframework.context.support.ClassPathXmlApplicationContext;

importjava.util.concurrent.CountDownLatch;

@Slf4j

publicclass DemoServiceConsumer {

    public static void main(String[] args)throws Exception {

        ClassPathXmlApplicationContext context= new ClassPathXmlApplicationContext(new String[] {"dubbo-demo-consumer.xml" });

        context.start();

        DemoService demoService = (DemoService)context.getBean("demoService");

        /** 单个测试 */

        String resInfo =demoService.sayHello("world");

        String serverIP =RpcContext.getContext().getRemoteHost();

        int serverPort =RpcContext.getContext().getRemotePort();

        System.out.println("rspInfo:" + resInfo + ", response from provider: " + serverIP +"," + serverPort);

           }

}

4 启动DemoServiceConsumer模拟一个单次的消费过程.这里输入world.我们可以看一下消费者日志:

 5    此时提供者端收到消费者的请求,提供者日志如下:

         到此为止,我们基本上完成了对Dubbo的Provider和Customer的示例,而在实际的项目应用中也是在此基础之上不断的增加服务,基本上的原理和配置本篇和上篇的示例基本上可以满足需求,但是还有一些特殊的需求和在实际开发项目中遇到的问题,这些就不够了,还需要对Dubbo的一些深层的配置和属性进行了解.