本篇是基于spring框架的XML配置开发的dubbo应用程序，开发工具intellij idea，旨在对dubbo的快速理解和上手。
废话不多说，代码撸起来！！！
1.首先，新建一个maven工程，命名为dubbodemo，右击dubbodemo，新建module，如图
建立三个子项目，分别命名为dubbo-demo-api，dubbo-demo-consumer，dubbo-demo-provider
2.根目录下pom.xml文件配置如下
<?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.nari</groupId>
<artifactId>dubbo-demo</artifactId>
<packaging>pom</packaging>
<version>1.0-SNAPSHOT</version>
<modules>
<module>dubbo-demo-api</module>
<module>dubbo-demo-provider</module>
<module>dubbo-demo-consumer</module>
</modules> <dependencies>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.5</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.5</version>
</dependency> <dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-lang3</artifactId>
<version>3.3.2</version>
</dependency> <dependency>
<groupId>commons-io</groupId>
<artifactId>commons-io</artifactId>
<version>2.4</version>
</dependency> <!-- spring -->
<!-- https://mvnrepository.com/artifact/org.springframework/spring-context -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>5.1.5.RELEASE</version>
</dependency> <!-- https://mvnrepository.com/artifact/org.springframework/spring-core -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>5.1.5.RELEASE</version>
</dependency> <!-- https://mvnrepository.com/artifact/org.springframework/spring-beans -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-beans</artifactId>
<version>5.1.5.RELEASE</version>
</dependency> <!-- https://mvnrepository.com/artifact/org.springframework/spring-web -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>5.1.5.RELEASE</version>
</dependency> <!-- https://mvnrepository.com/artifact/org.springframework/spring-webmvc -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>5.1.5.RELEASE</version>
</dependency> <!-- https://mvnrepository.com/artifact/org.springframework/spring-test -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>5.1.5.RELEASE</version>
<scope>test</scope>
</dependency> <!-- https://mvnrepository.com/artifact/org.springframework/spring-jdbc -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>5.1.5.RELEASE</version>
</dependency> <!-- https://mvnrepository.com/artifact/org.springframework/spring-tx -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
<version>5.1.5.RELEASE</version>
</dependency> <!-- https://mvnrepository.com/artifact/org.springframework/spring-oxm -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-oxm</artifactId>
<version>5.1.5.RELEASE</version>
</dependency> <!-- https://mvnrepository.com/artifact/org.apache.dubbo/dubbo -->
<dependency>
<groupId>org.apache.dubbo</groupId>
<artifactId>dubbo</artifactId>
<version>2.7.0</version>
</dependency>
<!--<dependency>
<groupId>org.apache.zookeeper</groupId>
<artifactId>zookeeper</artifactId>
<version>3.4.13</version>
</dependency>
<dependency>
<groupId>com.101tec</groupId>
<artifactId>zkclient</artifactId>
<version>0.8</version>
</dependency>-->
</dependencies> </project>
3.服务的提供方提供接口，如图所示，在dubbo-demo-api中新建一个interface接口，DemoService
package com.nari.api;
public interface DemoService {
String sayHello(String name);
}
pom文件如下
<?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">
<parent>
<artifactId>dubbo-demo</artifactId>
<groupId>com.nari</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion> <artifactId>dubbo-demo-api</artifactId> </project>
4.dubbo-demo-provider目录下，引入对dubbo-demo-api依赖。新建DemoServiceImpl类实现DemoService接口，如图所示
pom.xml文件如下
<?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">
<parent>
<artifactId>dubbo-demo</artifactId>
<groupId>com.nari</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion> <artifactId>dubbo-demo-provider</artifactId> <dependencies>
<dependency>
<artifactId>dubbo-demo-api</artifactId>
<groupId>com.nari</groupId>
<version>1.0-SNAPSHOT</version>
</dependency> </dependencies> </project>
DemoServiceImpl.java
package com.nari.provider;
import com.nari.api.DemoService;
public class DemoServiceImpl implements DemoService {
public String sayHello(String name) {
return "hello " + name;
}
}
在resources目录下新建provider.xml文件，使用广播multicast作为注册中心，优点是易于操作，不用做其他配置。dubbo服务端口为20880，<dubbo:service>暴露服务端口demoService
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:dubbo="http://dubbo.apache.org/schema/dubbo"
xmlns="http://www.springframework.org/schema/beans"
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"> <!-- provider's application name, used for tracing dependency relationship -->
<dubbo:application name="demo-provider">
<dubbo:parameter key="qos.enable" value="true" />
<dubbo:parameter key="qos.accept.foreign.ip" value="false" />
<dubbo:parameter key="qos.port" value="22222" />
</dubbo:application>
<!-- use multicast registry center to export service -->
<dubbo:registry address="multicast://224.5.6.7:1234" check="false"/>
<!-- use dubbo protocol to export service on port 20880 -->
<dubbo:protocol name="dubbo" port="20880"/>
<!-- service implementation, as same as regular local bean -->
<bean id="demoService" class="com.nari.provider.DemoServiceImpl"/>
<!-- declare the service interface to be exported -->
<dubbo:service interface="com.nari.api.DemoService" ref="demoService"/>
</beans>
新建provider.java，读取xml配置文件，代码如下
package com.nari.provider.main;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import java.io.IOException;
public class Provider {
public static void main(String[] args) {
try {
System.setProperty("java.net.preferIPv4Stack", "true");
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(new String[]{"META-INF/spring/provider.xml"});
context.start();
System.out.println("Provider started....");
System.in.read();
}catch (IOException e){
e.printStackTrace();
}
}
}
在resources目录下引入log4j.properties，开启日志功能
###set log levels###
log4j.rootLogger=info, stdout
###output to the console###
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=[%d{dd/MM/yy hh:mm:ss:sss z}] %t %5p %c{2}: %m%n
5.dubbo-demo-consumer目录下，对暴露的接口调用，获取服务，文件目录如下
pom.xml文件配置如下
<?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">
<parent>
<artifactId>dubbo-demo</artifactId>
<groupId>com.nari</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion> <artifactId>dubbo-demo-consumer</artifactId> <dependencies>
<dependency>
<artifactId>dubbo-demo-provider</artifactId>
<groupId>com.nari</groupId>
<version>1.0-SNAPSHOT</version>
</dependency>
</dependencies> </project>
在resources目录下新建consumer.xml文件，声明注册中心为multicast，地址与provider.xml文件中保持一致，<dubbo:reference>引入接口，调用服务。添加log4j.properties日志文件。
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:dubbo="http://dubbo.apache.org/schema/dubbo"
xmlns="http://www.springframework.org/schema/beans"
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"> <!-- consumer's application name, used for tracing dependency relationship (not a matching criterion),
don't set it same as provider -->
<dubbo:application name="demo-consumer">
<dubbo:parameter key="qos.enable" value="true" />
<dubbo:parameter key="qos.accept.foreign.ip" value="false" />
<dubbo:parameter key="qos.port" value="33333" />
</dubbo:application>
<!-- use multicast registry center to discover service -->
<dubbo:registry address="multicast://224.5.6.7:1234" check="false"/>
<!-- generate proxy for the remote service, then demoService can be used in the same way as the
local regular interface -->
<dubbo:reference id="demoService" check="false" interface="com.nari.api.DemoService"/>
<!--<dubbo:consumer check="false" />-->
</beans>
新建consumer.java文件，context上下文获取bean服务，调用其方法
package com.nari.consumer.main; import com.nari.api.DemoService;
import org.springframework.context.support.ClassPathXmlApplicationContext; public class Consumer { public static void main(String[] args) {
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(new String[]{"META-INF/spring/consumer.xml"});
context.start();
DemoService demoService = (DemoService) context.getBean("demoService");
String hello = demoService.sayHello("zhangsan");
System.out.println(hello);
} }
6.至此，工程搭建完成，先启动Provider.main()方法，服务的提供方提供服务，如图，打印结果如下
再启动Consumer.main()方法，服务的消费方成功获取到服务，打印结果如下：
