分布式系统_进程间通信_dubbo使用入门

Dubbo简介

DUBBO是一个分布式服务框架，致力于提供高性能和透明化的RPC远程服务调用方案，是阿里巴巴SOA服务化治理方案的核心框架，每天为2,000+个服务提供3,000,000,000+次访问量支持，并被广泛应用于阿里巴巴集团的各成员站点。

Dubbo RPC框架不同于一般的RPC框架的地方在于，Dubbo RPC的目的在于实现SOA服务的治理和服务管理。其通过服务注册中心来发现服务，并通过服务中心来分发服务来实现服务的负载均衡，通过服务发现来解耦服务，使得整个服务能力可以高效地进行扩展。

Dubbo使用入门

本章节结合Spring Boot 1.3.12.RELEASE和Dubbo来讲解，Dubbo的使用说明。Dubbo　RPC的基本结构中包括了，服务提供者和服务消费者。下面分别从服务提供者和服务消费者来说明。

dubbo-provider

基本的代码结构说明

dubbo-provider    src       main        com.egoo            service                Demo.java                DemoImpl.java            Application.java      resources        dubbo            provider.xml

pom.xml

<?xml version="1.0" encoding="UTF-8"?><project xmlns="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">    <modelVersion>4.0.0</modelVersion>    <groupId>com.egoo</groupId>    <artifactId>dubbo-provider</artifactId>    <version>1.0-SNAPSHOT</version>    <properties>        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>        <java.version>1.7</java.version>        <dubbo.version>2.4.10</dubbo.version>    </properties>    <dependencies>        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-starter</artifactId>            <exclusions>                <exclusion>                    <groupId>org.springframework.boot</groupId>                    <artifactId>spring-boot-starter-logging</artifactId>                </exclusion>            </exclusions>        </dependency>        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-starter-logging</artifactId>        </dependency>        <!-- RPC -->        <dependency>            <groupId>com.alibaba</groupId>            <artifactId>dubbo</artifactId>            <version>${dubbo.version}</version>            <exclusions>                <exclusion>                    <artifactId>spring</artifactId>                    <groupId>org.springframework</groupId>                </exclusion>            </exclusions>        </dependency>    </dependencies>    <dependencyManagement>        <dependencies>            <dependency>                <groupId>org.springframework.boot</groupId>                <artifactId>spring-boot-starter</artifactId>                <version>1.3.2.RELEASE</version>                <scope>import</scope>                <type>pom</type>            </dependency>        </dependencies>    </dependencyManagement>    <build>        <plugins>            <plugin>                <groupId>org.springframework.boot</groupId>                <artifactId>spring-boot-maven-plugin</artifactId>                <version>1.3.2.RELEASE</version>                <executions>                    <execution>                        <goals>                            <goal>repackage</goal>                        </goals>                    </execution>                </executions>            </plugin>            <plugin>                <groupId>org.apache.maven.plugins</groupId>                <artifactId>maven-compiler-plugin</artifactId>                <version>3.1</version>                <configuration>                    <fork>true</fork>                    <meminitial>512m</meminitial>                    <maxmem>1048m</maxmem>                </configuration>            </plugin>        </plugins>    </build></project>

应用配置
resources->dubbo->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://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       ">    <!-- 提供方应用信息，用于计算依赖关系 -->    <dubbo:application name="DemoProvider"  />    <!-- 使用multicast广播注册中心暴露服务地址 -->    <dubbo:registry address="multicast://224.5.6.7:1234" />    <!-- 用dubbo协议在20880端口暴露服务 -->    <dubbo:protocol name="dubbo" port="20880" />    <bean id="demoImpl" class="com.egoo.service.DemoImpl" />    <!-- service -->    <!--将接口暴露给服务中心-->    <dubbo:service interface="com.egoo.service.Demo" version="1.0.0" ref="demoImpl"  id="demo" /></beans>

创建对应的服务

服务接口package com.egoo.service;/** * Created by fiboliu on 16-5-3. */public interface Demo {    String greeting(String message);}服务实现package com.egoo.service;/** * Created by fiboliu on 16-5-3. */public class DemoImpl implements Demo {    public String greeting(String message) {        return message;    }}

Application.java //main function

package com.egoo;import org.springframework.boot.SpringApplication;import org.springframework.context.annotation.ImportResource;import java.io.IOException;/** * Created by fiboliu on 16-5-3. */@ImportResource({"classpath:dubbo/provider.xml"})public class Application {    public static void main(String args[]) {        SpringApplication.run(Application.class, args);        try {            System.out.println("启动成功,按任意键关闭");            System.in.read();        } catch (IOException e) {            e.printStackTrace();        }    }}

dubbo-consumer

基本的代码结构说明

dubbo-consumer    src       main        com.egoo            service                Demo.java            Application.java      resources        dubbo.properties        dubbo            consumer.xml

pom.xml

<?xml version="1.0" encoding="UTF-8"?><project xmlns="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">    <modelVersion>4.0.0</modelVersion>    <groupId>com.egoo</groupId>    <artifactId>dubbo-consumer</artifactId>    <version>1.0-SNAPSHOT</version>    <properties>        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>        <java.version>1.7</java.version>        <dubbo.version>2.4.10</dubbo.version>    </properties>    <dependencies>        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-starter</artifactId>            <exclusions>                <exclusion>                    <groupId>org.springframework.boot</groupId>                    <artifactId>spring-boot-starter-logging</artifactId>                </exclusion>            </exclusions>        </dependency>        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-starter-logging</artifactId>        </dependency>        <!-- RPC -->        <dependency>            <groupId>com.alibaba</groupId>            <artifactId>dubbo</artifactId>            <version>${dubbo.version}</version>            <exclusions>                <exclusion>                    <artifactId>spring</artifactId>                    <groupId>org.springframework</groupId>                </exclusion>            </exclusions>        </dependency>    </dependencies>    <dependencyManagement>        <dependencies>            <dependency>                <groupId>org.springframework.boot</groupId>                <artifactId>spring-boot-starter</artifactId>                <version>1.3.2.RELEASE</version>                <scope>import</scope>                <type>pom</type>            </dependency>        </dependencies>    </dependencyManagement>    <build>        <plugins>            <plugin>                <groupId>org.springframework.boot</groupId>                <artifactId>spring-boot-maven-plugin</artifactId>                <version>1.3.2.RELEASE</version>                <executions>                    <execution>                        <goals>                            <goal>repackage</goal>                        </goals>                    </execution>                </executions>            </plugin>            <plugin>                <groupId>org.apache.maven.plugins</groupId>                <artifactId>maven-compiler-plugin</artifactId>                <version>3.1</version>                <configuration>                    <fork>true</fork>                    <meminitial>512m</meminitial>                    <maxmem>1048m</maxmem>                </configuration>            </plugin>        </plugins>    </build></project>

resources文件
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://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       ">    <!-- 提供方应用信息，用于计算依赖关系 -->    <dubbo:application name="DemoConsumer"  />    <!-- 使用multicast广播注册中心暴露服务地址 -->    <dubbo:registry address="multicast://224.5.6.7:1234" />    <!-- 用dubbo协议在20880端口暴露服务 -->    <dubbo:protocol name="dubbo" port="20880" />    <dubbo:reference id="demo" interface="com.egoo.service.Demo" version="1.0.0" /></beans>

dubbo.properties

### Copyright 1999-2011 Alibaba Group.## Licensed under the Apache License, Version 2.0 (the "License");# you may not use this file except in compliance with the License.# You may obtain a copy of the License at##      http://www.apache.org/licenses/LICENSE-2.0## Unless required by applicable law or agreed to in writing, software# distributed under the License is distributed on an "AS IS" BASIS,# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.# See the License for the specific language governing permissions and# limitations under the License.##dubbo.container=log4j,springdubbo.application.name=consumerdubbo.application.owner=egoodubbo.registry.address=multicast://224.5.6.7:1234#dubbo.registry.address=zookeeper://127.0.0.1:2181#dubbo.registry.address=redis://127.0.0.1:6379#dubbo.registry.address=dubbo://127.0.0.1:9090#dubbo.monitor.protocol=registrydubbo.log4j.file=logs/dubbo-demo-consumer.logdubbo.log4j.level=WARN

接口文件(保证和provider接口文件一致)

package com.egoo.service;/** * Created by fiboliu on 16-5-3. */public interface Demo {    String greeting(String message);}

Application.java

package com.egoo;import com.egoo.service.Demo;import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication;import org.springframework.context.ApplicationContext;import org.springframework.context.annotation.ImportResource;/** * Created by fiboliu on 16-5-3. */@SpringBootApplication@ImportResource({"classpath:dubbo/consumer.xml"})public class Application {    public static void main(String args[]) {        ApplicationContext context = SpringApplication.run(Application.class, args);        Demo demo = (Demo) context.getBean("demo");        System.out.println(demo.greeting("hello world!!"));    }}