搜索
您的当前位置:首页正文

分布式RPC框架Apache Dubbo(一)

来源:二三娱乐

4 Dubbo快速入门

Dubbo作为一个RPC框架,其最核心的功能就是要实现跨网络的远程调用。本小节就是要创建两个应用,一个作为服务的提供方,一个作为服务的消费方。通过Dubbo来实现服务消费方远程调用服务提供方的方法。

4.1 服务提供方开发

开发步骤:

(1)创建maven工程(打包方式为war)dubbodemo_provider,在pom.xml文件中导入如下坐标

 <packaging>war</packaging>
<properties>
  <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  
  
  <spring.version>5.0.5.RELEASE</spring.version>
</properties>
<dependencies>
  <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-context</artifactId>
    <version>${spring.version}</version>
  </dependency>
  <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-beans</artifactId>
    <version>${spring.version}</version>
  </dependency>
  <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-webmvc</artifactId>
    <version>${spring.version}</version>
  </dependency>
  <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-jdbc</artifactId>
    <version>${spring.version}</version>
  </dependency>
  <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-aspects</artifactId>
    <version>${spring.version}</version>
  </dependency>
  <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-jms</artifactId>
    <version>${spring.version}</version>
  </dependency>
  <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-context-support</artifactId>
    <version>${spring.version}</version>
  </dependency>
  <!-- dubbo相关 -->
  <dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>dubbo</artifactId>
    <version>2.6.0</version>
  </dependency>
  <dependency>
    <groupId>org.apache.zookeeper</groupId>
    <artifactId>zookeeper</artifactId>
    <version>3.4.7</version>
  </dependency>
  <dependency>
    <groupId>com.github.sgroschupf</groupId>
    <artifactId>zkclient</artifactId>
    <version>0.1</version>
  </dependency>
  <dependency>
    <groupId>javassist</groupId>
    <artifactId>javassist</artifactId>
    <version>3.12.1.GA</version>
  </dependency>
  <dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.2.47</version>
  </dependency>
</dependencies>
<build>
  <plugins>
    <plugin>
      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-compiler-plugin</artifactId>
      <version>2.3.2</version>
      <configuration>
        <source>1.8</source>
        <target>1.8</target>
      </configuration>
    </plugin>
    <plugin>
      <groupId>org.apache.tomcat.maven</groupId>
      <artifactId>tomcat7-maven-plugin</artifactId>
      <configuration>
        <!-- 指定端口 -->
        <port>8081</port>
        <!-- 请求路径 -->
        <path>/</path>
      </configuration>
    </plugin>
  </plugins>
</build>

(2)配置web.xml文件

创建 webapp/WEB-INF/web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
         version="3.1">
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>classpath:applicationContext*.xml</param-value>
    </context-param>
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>

</web-app>

(3)创建服务接口

package com.maweiqi.service;

/**
 * HelloService
 *
 * @Author: 马 伟 奇
 * @CreateTime: 2019-07-18
 * @Description:
 */
public interface HelloService {
    public String sayHello(String name);
}

(4)创建服务实现类

package com.maweiqi.service.impl;

import com.alibaba.dubbo.config.annotation.Service;
import com.maweiqi.service.HelloService;

/**
 * HelloServiceImpl
 *
 * @Author: 马 伟 奇
 * @CreateTime: 2019-07-18
 * @Description:
 */
@Service
public class HelloServiceImpl implements HelloService {
    @Override
    public String sayHello(String name) {
        return "hello " + name;
    }
}

注意:服务实现类上使用的Service注解是Dubbo提供的,用于对外发布服务

(5)在src/main/resources下创建applicationContext-service.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans 
       
       
       
       
       
       
        
         
         
         
         
         
         
    <!-- 当前应用名称,用于注册中心计算应用间依赖关系,注意:消费者和提供者应用名不要一样 -->
    <dubbo:application name="dubbodemo_provider" />
    <!-- 连接服务注册中心zookeeper ip为zookeeper所在服务器的ip地址-->
    <dubbo:registry address="zookeeper://127.0.0.1:2181"/>
    <!-- 注册  协议和port   端口默认是20880 -->
    <dubbo:protocol name="dubbo" port="20881"></dubbo:protocol>
    <!-- 扫描指定包,加入@Service注解的类会被发布为服务  -->
    <dubbo:annotation package="com.maweiqi.service.impl" />
</beans>

(6)启动服务


启动服务

4.2 服务消费方开发

开发步骤:

(1)创建maven工程(打包方式为war)dubbodemo_consumer,pom.xml配置和上面服务提供者相同,只需要将Tomcat插件的端口号改为8082即可

    <packaging>war</packaging>
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        
        
        <spring.version>5.0.5.RELEASE</spring.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-beans</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aspects</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jms</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context-support</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <!-- dubbo相关 -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>dubbo</artifactId>
            <version>2.6.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.zookeeper</groupId>
            <artifactId>zookeeper</artifactId>
            <version>3.4.7</version>
        </dependency>
        <dependency>
            <groupId>com.github.sgroschupf</groupId>
            <artifactId>zkclient</artifactId>
            <version>0.1</version>
        </dependency>
        <dependency>
            <groupId>javassist</groupId>
            <artifactId>javassist</artifactId>
            <version>3.12.1.GA</version>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.47</version>
        </dependency>
       
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>2.3.2</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.tomcat.maven</groupId>
                <artifactId>tomcat7-maven-plugin</artifactId>
                <configuration>
                    <!-- 指定端口 -->
                    <port>8082</port>
                    <!-- 请求路径 -->
                    <path>/</path>
                </configuration>
            </plugin>
        </plugins>
    </build>

(2)配置web.xml文件

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
         version="3.1">

 <servlet>
    <servlet-name>springmvc</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <!-- 指定加载的配置文件 ,通过参数contextConfigLocation加载 -->
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:applicationContext-web.xml</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>springmvc</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>

</web-app>

(3)将服务提供者工程中的HelloService接口复制到当前工程

package com.maweiqi.service;

/**
 * HelloService
 *
 * @Author: 马伟奇
 * @CreateTime: 2019-07-18
 * @Description:
 */
public interface HelloService {
    public String sayHello(String name);
}

(4)编写Controller

package com.maweiqi.controller;

import com.alibaba.dubbo.config.annotation.Reference;
import com.maweiqi.service.HelloService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

/**
 * HelloController
 *
 * @Author: 马伟奇
 * @CreateTime: 2019-07-19
 * @Description:
 */
@Controller
@RequestMapping("/demo")
public class HelloController {
    @Reference
    private HelloService helloService;

    @RequestMapping("/hello")
    @ResponseBody
    public String getName(String name){
        //远程调用
        String result = helloService.sayHello(name);
        System.out.println(result);
        return result;
    }
}

注意:Controller中注入HelloService使用的是Dubbo提供的@Reference注解

(5)在src/main/resources下创建applicationContext-web.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans 
       
       
       
       
       
       
            
            
            
            
            
            
            

    <!-- 当前应用名称,用于注册中心计算应用间依赖关系,注意:消费者和提供者应用名不要一样 -->
    <dubbo:application name="dubbodemo-consumer" />
    <!-- 连接服务注册中心zookeeper ip为zookeeper所在服务器的ip地址-->
    <dubbo:registry address="zookeeper://127.0.0.1:2181"/>
    <!-- 扫描的方式暴露接口  -->
    <dubbo:annotation package="com.maweiqi.controller" />
</beans>

(6)运行测试

运行
在浏览器输入,查看浏览器输出结果

4.3 代码重构

① 创建项目:dubbodemo_interface


创建项目

② 把 项目dubbodemo_consumer 和 项目dubbodemo_provider当中的 接口 HelloService 拷贝到dubbodemo_interface工程里面


image.png
③ 删除工程dubbodemo_consumer 和 工程dubbodemo_provider当中的 接口 HelloService
image.png

dubbodemo_consumer 工程和dubbodemo_provider添加pom文件的依赖

<dependency>
    <groupId>com.maweiqi</groupId>
    <artifactId>dubbodemo_interface</artifactId>
    <version>1.0-SNAPSHOT</version>
</dependency>
获取数据

5. Dubbo管理控制台

我们在开发时,需要知道Zookeeper注册中心都注册了哪些服务,有哪些消费者来消费这些服务。我们可以通过部署一个管理中心来实现。其实管理中心就是一个web应用,部署到tomcat即可。

5.1 安装

安装步骤:

(1)将资料中的dubbo-admin-2.6.0.war文件复制到tomcat的webapps目录下


image.png

(2)启动tomcat,此war文件会自动解压


image.png
(3)修改WEB-INF下的dubbo.properties文件,注意dubbo.registry.address对应的值需要对应当前使用的Zookeeper的ip地址和端口号
dubbo.registry.address=zookeeper://192.168.134.129:2181
dubbo.admin.root.password=root
dubbo.admin.guest.password=guest
image.png

(4)重启tomcat

5.2 使用

操作步骤:

image.png
(2)启动服务提供者工程和服务消费者工程,可以在查看到对应的信息
image.png
image.png
Top