Dubbo 02: 直连式

直连式

• 需要用到两个相互独立的maven的web项目

  项目1:o1-link-userservice-provider	作为服务的提供者
  项目2:o2-link-consumer	作为使用服务的消费者
  

项目1

• 结构

  

• pom文件

  <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/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.example.dubbo</groupId>
    <artifactId>o1-link-userservice-provider</artifactId>
    <packaging>war</packaging>
    <version>1.0.0</version>
  
    <dependencies>
      <!--Spring依赖-->
      <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>4.3.16.RELEASE</version>
      </dependency>
      <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>4.3.16.RELEASE</version>
      </dependency>
  
      <!--dubbo依赖-->
      <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>dubbo</artifactId>
        <version>2.6.2</version>
      </dependency>
  
    </dependencies>
  
    <build>
      <plugins>
        <!--JDK1.8编译插件-->
        <plugin>
          <artifactId>maven-compiler-plugin</artifactId>
          <version>3.1</version>
          <configuration>
            <source>1.8</source>
            <target>1.8</target>
          </configuration>
        </plugin>
      </plugins>
    </build>
  </project>
  

• 实体类：注意要实现序列化接口，数据需要通过socket网络传输

  package com.example.dubbo.model;
  
  import java.io.Serializable;
  
  public class User implements Serializable {
      private String id;
      private String name;
      private String age;
  
      @Override
      public String toString() {
          return "User{" +
                  "id='" + id + '\'' +
                  ", name='" + name + '\'' +
                  ", age='" + age + '\'' +
                  '}';
      }
  
      public String getId() {
          return id;
      }
  
      public void setId(String id) {
          this.id = id;
      }
  
      public String getName() {
          return name;
      }
  
      public void setName(String name) {
          this.name = name;
      }
  
      public String getAge() {
          return age;
      }
  
      public void setAge(String age) {
          this.age = age;
      }
  
      public User(String id, String name, String age) {
          this.id = id;
          this.name = name;
          this.age = age;
      }
  
      public User() {
      }
  }
  

• 服务接口

  package com.example.dubbo.service;
  
  import com.example.dubbo.model.User;
  
  public interface UserService {
      /**
       * 根据用户id，获取用信息
       */
      User queryUserById(String id);
  }
  

• 服务接口的实现类

  package com.example.dubbo.service.impl;
  
  import com.example.dubbo.model.User;
  import com.example.dubbo.service.UserService;
  
  public class UserServiceImpl implements UserService {
  
      /**
       * 根据用户id，获取用户信息
       */
      @Override
      public User queryUserById(String id) {
          User user = new User();
          user.setId(id);
          user.setName("橘子");
          user.setAge("21");
          return user;
      }
  }
  

• dubbo框架里的服务提供者所对应的配置文件：dubbo-link-userservice-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://dubbo.apache.org/schema/dubbo"
         xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://dubbo.apache.org/schema/dubbo http://dubbo.apache.org/schema/dubbo/dubbo.xsd">
  
      <!-- 对外提供的服务的名称，要具有唯一性-->
      <dubbo:application name="o1-link-userservice-provider"/>
      <!-- 服务使用的协议以及端口号 -->
      <dubbo:protocol name="dubbo" port="20880"/>
      <!-- 服务对外提供的接口 -->
      <dubbo:service interface="com.example.dubbo.service.UserService" ref="userService" registry="N/A"/>
      <!-- 对外提供的接口的实现类-->
      <bean id="userService" class="com.example.dubbo.service.impl.UserServiceImpl"/>
  
  </beans>
  

• web.xml

  <?xml version="1.0" encoding="UTF-8"?>
  <web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
           version="4.0">
  
      <!-- 将dubbo框架交给spring框架管理 -->
      <context-param>
          <param-name>contextConfigLocation</param-name>
          <param-value>classpath:dubbo-link-userservice-provider.xml</param-value>
      </context-param>
      <listener>
          <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
      </listener>
  </web-app>
  

注意

• 由于采用的是直连方式，要把项目1，打成jar包，后面项目2会引用这个jar包

• 项目1打成jar包的步骤

  1.将项目1的pom文件中的<packaging>war</packaging>注释掉，这样打包的时候默认会打成jar包
  2.点击maven项目管理中的项目1的Lifecycle里的install(操作见下图)
  3.把注释放开
  

  

项目2

• 结构

  

• pom文件：其中要根据项目1的坐标将之前把项目1打成的jar包引入项目2中使用

  <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/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.example.dubbo</groupId>
    <artifactId>o2-link-consumer</artifactId>
    <packaging>war</packaging>
    <version>1.0.0</version>
  
  <dependencies>
    <!--Spring依赖-->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-context</artifactId>
      <version>4.3.16.RELEASE</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-webmvc</artifactId>
      <version>4.3.16.RELEASE</version>
    </dependency>
  
    <!--dubbo依赖-->
    <dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>dubbo</artifactId>
      <version>2.6.2</version>
    </dependency>
  
    <!-- 对01-link-userservice-provider项目的依赖-->
    <dependency>
      <groupId>com.example.dubbo</groupId>
      <artifactId>o1-link-userservice-provider</artifactId>
      <version>1.0.0</version>
    </dependency>
  </dependencies>
  
    <build>
      <plugins>
        <!--JDK1.8编译插件-->
        <plugin>
          <artifactId>maven-compiler-plugin</artifactId>
          <version>3.1</version>
          <configuration>
            <source>1.8</source>
            <target>1.8</target>
          </configuration>
        </plugin>
      </plugins>
    </build>
  </project>
  

• dubbo框架里的消费者所对应的配置文件：dubbo-link-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://dubbo.apache.org/schema/dubbo"
         xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://dubbo.apache.org/schema/dubbo http://dubbo.apache.org/schema/dubbo/dubbo.xsd">
  
      <!-- 消费者的唯一标识-->
      <dubbo:application name="o2-link-consumer"/>
  
      <!-- 引用的远程服务的相关信息 -->
      <dubbo:reference id="userService" interface="com.example.dubbo.service.UserService" url="dubbo://127.0.0.1:20880" registry="N/A"/>
  </beans>
  

• spring核心配置文件：application.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:context="http://www.springframework.org/schema/context"
         xmlns:mvc="http://www.springframework.org/schema/mvc"
         xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd">
  
      <!-- 扫描控制层 -->
      <context:component-scan base-package="com.example.dubbo.web.controller"/>
  
      <!-- 配置注解驱动 -->
      <mvc:annotation-driven/>
  
      <!-- 配置视图解析器-->
      <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
          <property name="prefix" value="/"/>
          <property name="suffix" value=".jsp"/>
      </bean>
  </beans>
  

• Controller层

  import org.springframework.stereotype.Controller;
  import org.springframework.ui.Model;
  import org.springframework.web.bind.annotation.RequestMapping;
  
  @Controller
  public class UserController {
      @Autowired
      UserService userService;
  
      /**
       * 接收前端请求，查询数据并返回
       */
      @RequestMapping("/getUser.do")
      public String getUser(String id, Model model){
          //获取数据
          User user = userService.queryUserById(id);
          //存放数据
          model.addAttribute("user", user);
          //返回到用户详情页面
          return "userDetail";
      }
  }
  

• web.xml

  <?xml version="1.0" encoding="UTF-8"?>
  <web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
           version="4.0">
  
      <servlet>
          <servlet-name>dispatcherServlet</servlet-name>
          <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
          <init-param>
              <param-name>contextConfigLocation</param-name>
              <param-value>classpath:application.xml, classpath:dubbo-link-consumer.xml</param-value>
          </init-param>
      </servlet>
      <servlet-mapping>
          <servlet-name>dispatcherServlet</servlet-name>
          <url-pattern>*.do</url-pattern>
      </servlet-mapping>
  </web-app>
  

• 返回给前端的用户详情页面：userDetail.jsp

  <%@ page contentType="text/html;charset=UTF-8" language="java" %>
  <html>
  <head>
      <title>用户详情页面</title>
  </head>
  <body>
  <div>用户标识:${user.id}</div>
  <div>用户名称:${user.name}</div>
  <div>用户年龄:${user.age}</div>
  </body>
  </html>
  

测试

• 将项目1(服务提供者)和项目2(消费者)，分别部署到tomcat服务器上并启动服务器

  

• 从消费者端去访问获取服务

  

直连缺点

• 由于事先要把项目1打成jar包，项目2中依赖项目1的jar包，上述方式虽然实现了消费者对服务的访问，但是上述直连方式并没有实现服务提供者和消费者的真正分离，业务还是耦合在一个项目中(这里是耦合在项目2里)