[dubbo入门] dubbo入门

使用dubbo实现一个远程的RPC调用的过程：

1.定义一个服务接口
服务接口ISayHello

public interface ISayHello {        ObjectResponse sayHello(ObjectRequest objectRequest);}

接口参数需要序列化

public class ObjectRequest implements Serializable {    private static final long serialVersionUID = -8141279374881183198L;    private String name;    public ObjectRequest(String name) {        this.name = name;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    @Override    public String toString() {        return "ObjectRequest{" +                "name='" + name + '\'' +                '}';    }}

返回对象也需要序列化

public class ObjectResponse implements Serializable {    private static final long serialVersionUID = -6961033674286036464L;    private String name;    public ObjectResponse(String name) {        this.name = name;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    @Override    public String toString() {        return "ObjectResponse{" +                "name='" + name + '\'' +                '}';    }}

2.实现一个Provider
Provider是一个服务提供者，
第一步：需要实现服务接口

public class SayHelloImpl implements ISayHello {    public ObjectResponse sayHello(ObjectRequest objectRequest) {        String name = objectRequest.getName();         return new ObjectResponse(name);    }}

第二步：配置dubbo，在资源文件中创建META-INF/spring/xxx.xml文件

<beans xmlns="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">        <dubbo:application name="dubbo-provider" owner="luis"/>        //这个地方可以使用很多种方式，如注册中心等        <dubbo:registry address="N/A" />        //这地方可以使用dubbo、webservice等协议        <dubbo:protocol name="http" port="20881" />        //接口以及接口的实现类        <dubbo:service interface="dubbodemo.ISayHello" ref="sayHello"/>        //接口实现类bean        <bean id="sayHello" class="dubbodemo.SayHelloImpl" /></beans>

第三步：发布服务

public class App {    public static void main( String[] args ) throws IOException {        ClassPathXmlApplicationContext cac= new ClassPathXmlApplicationContext(new String[]{"META-INF/spring/dubbodemoprovider.xml"});        classPathXmlApplicationContext.start();        System.in.read();    }}

3.创建一个消费者Consumer
Consume想当然肯定是获取的Provider暴露出来的接口，根据上面Provider配置的方式，Consumer的配置方式如下所示：

<beans xmlns="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">    <dubbo:application name="dubbo-cusumer" owner="luis"/>    <dubbo:registry address="N/A" />    //url必须配置，url为 协议(此处配置为http)://ip地址+端口号/接口的全路径    <dubbo:reference id="sayHello" interface="dubbodemo.ISayHello" url="http://192.168.36.1:20881/dubbodemo.ISayHello" /></beans>

通过下面的方式来调用Provider提供的服务接口

public class App {    public static void main( String[] args )    {        ObjectRequest objectRequest = new ObjectRequest("luis");        ClassPathXmlApplicationContext cac = new ClassPathXmlApplicationContext(new String[]{"META-INF/spring/dubbodemocusumer.xml"});        cac.start();

一个简单的dubbo实现远程RPC的调用就已经完成

对比Provider和Consumer的配置文件
都需要配置的

dubbo:application name="dubbo-xxx" owner="luis"/>//注册中心的配置<dubbo:registry address="N/A" />

Provider需要配置的，发布服务之后都是已URL方式提供url包括 协议+ip+端口+接口的全称
以及Provider需要实现服务接口

<dubbo:protocol name="http" port="20881" /><dubbo:service interface="dubbodemo.ISayHello" ref="sayHello"/>

Consumer需要配置的，consumer主要关注需要引用服务接口，以及从哪里(url)引用的

<dubbo:reference id="sayHello" interface="dubbodemo.ISayHello" url="http://192.168.36.1:20881/dubbodemo.ISayHello" />