POJO 方式使用 Triple

这篇教程会通过从零构建一个简单的工程来演示如何基于 POJO 方式使用 Dubbo Triple, 在应用不改变已有接口定义的同时升级到 Triple 协议。 POJO on Triple 原理请参考POJO on Triple

前置条件

创建工程

  1. 首先创建一个空的 maven 工程

    $ mvn archetype:generate                                \
        -DgroupId=org.apache.dubbo                          \
        -DartifactId=tri-pojo-demo                          \
        -DarchetypeArtifactId=maven-archetype-quickstart    \
        -DarchetypeVersion=1.4                              \
        -DarchetypeGroupId=org.apache.maven.archetypes      \
        -Dversion=1.0-SNAPSHOT
    
  2. 切换到工程目录

    $ cd tri-pojo-demo
    
  3. pom.xml 中设置 JDK 版本,添加 Dubbo 依赖和插件

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
    </properties>
    
    <dependencies>
       <dependency>
           <groupId>junit</groupId>
           <artifactId>junit</artifactId>
           <version>4.13</version>
           <scope>test</scope>
       </dependency>
       <dependency>
           <groupId>org.apache.dubbo</groupId>
           <artifactId>dubbo</artifactId>
           <version>3.0.8</version>
       </dependency>
       <dependency>
        <groupId>org.apache.dubbo</groupId>
        <artifactId>dubbo-dependencies-zookeeper-curator5</artifactId>
        <type>pom</type>
        <version>3.0.8</version>
       </dependency>
        <dependency>
            <groupId>com.google.protobuf</groupId>
            <artifactId>protobuf-java</artifactId>
            <version>3.19.4</version>
        </dependency>
    </dependencies>
    
  4. 添加接口定义src/main/java/org/apache/dubbo/Greeter.java

    package org.apache.dubbo;
    
    public interface Greeter {
       String sayHello(String name);
    }
    
  5. 添加服务端接口实现src/main/java/org/apache/dubbo/GreeterImpl.java

    package org.apache.dubbo;
    
    public class GreeterImpl implements Greeter {
       @Override
       public String sayHello(String name) {
          return "Hello," + name + "!";
       }
    }
    
  6. 添加服务端启动类 src/main/java/org/apache/dubbo/MyDubboServer.java

    package org.apache.dubbo;
    
    import org.apache.dubbo.common.constants.CommonConstants;
    import org.apache.dubbo.config.ApplicationConfig;
    import org.apache.dubbo.config.ProtocolConfig;
    import org.apache.dubbo.config.RegistryConfig;
    import org.apache.dubbo.config.ServiceConfig;
    import org.apache.dubbo.config.bootstrap.DubboBootstrap;
    
    import java.io.IOException;
    
    public class MyDubboServer {
    
       public static void main(String[] args) throws IOException {
           ServiceConfig<Greeter> service = new ServiceConfig<>();
           service.setInterface(Greeter.class);
           service.setRef(new GreeterImpl());
    
           DubboBootstrap bootstrap = DubboBootstrap.getInstance();
           bootstrap.application(new ApplicationConfig("tri-pojo-server"))
                   .registry(new RegistryConfig("zookeeper://127.0.0.1:2181"))
                   .protocol(new ProtocolConfig(CommonConstants.TRIPLE, 50051))
                   .service(service)
                   .start();
           System.out.println("Dubbo triple pojo server started");
           System.in.read();
       }
    }
    
  7. 添加客户端启动类src/main/java/org/apache/dubbo/MyDubboClient.java

    package org.apache.dubbo;
    
    import org.apache.dubbo.common.constants.CommonConstants;
    import org.apache.dubbo.config.ApplicationConfig;
    import org.apache.dubbo.config.ReferenceConfig;
    import org.apache.dubbo.config.RegistryConfig;
    import org.apache.dubbo.config.bootstrap.DubboBootstrap;
    
    public class MyDubboClient {
       public static void main(String[] args) {
          DubboBootstrap bootstrap = DubboBootstrap.getInstance();
          ReferenceConfig<Greeter> ref = new ReferenceConfig<>();
          ref.setInterface(Greeter.class);
          ref.setProtocol(CommonConstants.TRIPLE);
          ref.setTimeout(3000);
          bootstrap.application(new ApplicationConfig("tri-pojo-client"))
           .registry(new RegistryConfig("zookeeper://127.0.0.1:2181"))
           .reference(ref)
           .start();
    
          Greeter greeter = ref.get();
          String reply = greeter.sayHello("pojo");
          System.out.println("Received reply:" + reply);
        }
    }
    
  8. 编译代码

    $ mvn clean install
    
  9. 启动服务端

    $ mvn org.codehaus.mojo:exec-maven-plugin:3.0.0:java -Dexec.mainClass="org.apache.dubbo.MyDubboServer"
    Dubbo triple pojo server started
    
  10. 打开新的终端,启动客户端

$ mvn org.codehaus.mojo:exec-maven-plugin:3.0.0:java -Dexec.mainClass="org.apache.dubbo.MyDubboClient"
Received reply:message: "Hello,Demo!"