dubbo入门第一课--简单项目

项目里在使用dubbo，我一直想要知道dubbo是干什么的，怎么用，具体的原理。
那么第一课，我首先来介绍dubbo能干什么？

1. dubbo能干什么？
   我以一个我们公司用到的简单功能来分析：我们是P2P平台，平台发布了一些标的供用户购买，首先用户需要登录网站，然后支付订单，然后平台结标开始起息。
   如果是传统的web应用，用户登录，支付订单，结标起息这三个功能块应该部署在一台机器上，然后顺序执行。随着业务量的增加，这一台服务器的压力越来越大，我们不能在这样一条直线式的把所有项目部署到一台机器上。这个时候就需要分布式系统了，我们可以把这块功能分解成三个独立的系统：用户系统，订单系统，结标起息系统，而且把这三个系统分别部署到三台服务器上，这样服务器的压力就小了很多。但是这样一来，就又麻烦了，这三台服务器之间怎么沟通呢？原来一台服务器，由于是本地调用，直接调用就可以了。可这里需要机器与机器时间交流了，如何做到远程通信像本地通信那样呢？
   其实到了这里，我们就可以知道Dubbo是一个分布式的RPC服务框架了。官方介绍的是：
   Dubbo 是一个分布式、高性能、透明化的 RPC 服务框架，提供服务自动注册、自动发现等高效服务治理方案。

2. 怎么用？
   我们已经大概知道dubbo是干什么的，现在就来聊聊怎么用吧。我的项目包含四个部分：

• spring-dubbo
  父项目
• spring-dubbo-api
  子项目，主要包括公共的东西，比如service,model之类的。
• spring-dubbo-provider
  服务的提供者，provider
• spring-dubbo-consumer
  dubbo的使用者，consumer.
  2.1 spring-dubbo
  这里看下pom.xml配置如下：

<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.wang.dubbo</groupId>
    <artifactId>spring-dubbo</artifactId>
    <version>${dubbodemo.version}</version>
    <packaging>pom</packaging>
    <name>spring-dubbo</name>
    <modules>
        <module>spring-dubbo-provider</module>
        <module>spring-dubbo-consumer</module>
        <module>spring-dubbo-api</module>
    </modules>

    <properties>
        <dubbodemo.version>0.0.1-SNAPSHOT</dubbodemo.version>
        <springside.version>4.1.0.GA</springside.version>
        <spring.version>4.0.9.RELEASE</spring.version>
        <jstl.version>1.2</jstl.version>
        <jackson.version>2.3.4</jackson.version>
        <commons-lang3.version>3.2.1</commons-lang3.version>
        <guava.version>14.0.1</guava.version>
        <commons-beanutils.version>1.9.2</commons-beanutils.version>
        <slf4j.version>1.7.10</slf4j.version>
        <logback.version>1.1.3</logback.version>
        <log4jdbc.version>1.15</log4jdbc.version>
        <lombok.version>1.16.4</lombok.version>
        <junit.version>4.12</junit.version>
        <jdk.version>1.8</jdk.version>
        <httpclient.version>4.5</httpclient.version>
        <aspectj.version>1.7.4</aspectj.version>
        <commons-collections.version>3.2.2</commons-collections.version>
    </properties>

    <dependencyManagement>
        <dependencies>
            <!-- SpringSide -->
            <dependency>
                <groupId>org.springside</groupId>
                <artifactId>springside-core</artifactId>
                <version>${springside.version}</version>
            </dependency>

            <!-- Spring MVC -->
            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-webmvc</artifactId>
                <version>${spring.version}</version>
            </dependency>

            <!-- Jackson -->
            <dependency>
                <groupId>com.fasterxml.jackson.core</groupId>
                <artifactId>jackson-databind</artifactId>
                <version>${jackson.version}</version>
            </dependency>
            <dependency>
                <groupId>com.fasterxml.jackson.module</groupId>
                <artifactId>jackson-module-jaxb-annotations</artifactId>
                <version>${jackson.version}</version>
            </dependency>
            <dependency>
                <groupId>com.fasterxml.jackson.datatype</groupId>
                <artifactId>jackson-datatype-joda</artifactId>
                <version>${jackson.version}</version>
            </dependency>
            <!-- Common Utilitis -->
            <dependency>
                <groupId>org.apache.commons</groupId>
                <artifactId>commons-lang3</artifactId>
                <version>${commons-lang3.version}</version>
            </dependency>
            <dependency>
                <groupId>com.google.guava</groupId>
                <artifactId>guava</artifactId>
                <version>${guava.version}</version>
            </dependency>
            <dependency>
                <groupId>commons-beanutils</groupId>
                <artifactId>commons-beanutils</artifactId>
                <version>${commons-beanutils.version}</version>
            </dependency>

            <dependency>
                <groupId>org.slf4j</groupId>
                <artifactId>slf4j-api</artifactId>
                <version>${slf4j.version}</version>
            </dependency>
            <dependency>
                <groupId>ch.qos.logback</groupId>
                <artifactId>logback-classic</artifactId>
                <version>${logback.version}</version>
            </dependency>
            <dependency>
                <groupId>org.slf4j</groupId>
                <artifactId>log4j-over-slf4j</artifactId>
                <version>${slf4j.version}</version>
            </dependency>
            <dependency>
                <groupId>org.slf4j</groupId>
                <artifactId>jcl-over-slf4j</artifactId>
                <version>${slf4j.version}</version>
            </dependency>
            <dependency>
                <groupId>org.slf4j</groupId>
                <artifactId>jul-to-slf4j</artifactId>
                <version>${slf4j.version}</version>
            </dependency>
            <dependency>
                <groupId>org.bgee.log4jdbc-log4j2</groupId>
                <artifactId>log4jdbc-log4j2-jdbc4</artifactId>
                <version>${log4jdbc.version}</version>
            </dependency>

            <!-- AOP -->
            <dependency>
                <groupId>org.aspectj</groupId>
                <artifactId>aspectjweaver</artifactId>
                <version>${aspectj.version}</version>
            </dependency>
            
            <dependency>
                <groupId>org.apache.httpcomponents</groupId>
                <artifactId>httpclient</artifactId>
                <version>${httpclient.version}</version>
            </dependency>

            <!-- Code Generator -->
            <dependency>
                <groupId>org.projectlombok</groupId>
                <artifactId>lombok</artifactId>
                <version>${lombok.version}</version>
            </dependency>
        </dependencies>
    </dependencyManagement>
    <build>
        <pluginManagement>
            <plugins>
                <!-- compiler插件, 设定JDK版本 -->
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-compiler-plugin</artifactId>
                    <version>3.3</version>
                    <configuration>
                        <source>${jdk.version}</source>
                        <target>${jdk.version}</target>
                        <showWarnings>true</showWarnings>
                    </configuration>
                </plugin>

                <!-- 忽略单元测试 -->
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-surefire-plugin</artifactId>
                    <version>2.18.1</version>
                    <configuration>
                        <skip>true</skip>
                    </configuration>
                </plugin>

                <!-- 生成域对象的QDomain -->
            </plugins>
        </pluginManagement>
    </build>
</project>

2.2 spring-dubbo-api
先看pom.xml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/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>com.wang.dubbo</groupId>
        <artifactId>spring-dubbo</artifactId>
        <version>${dubbodemo.version}</version>
    </parent>
    <artifactId>spring-dubbo-api</artifactId>
    <name>spring-dubbo-api</name>

    <dependencies>
        <!-- SpringSide -->
        <dependency>
            <groupId>org.springside</groupId>
            <artifactId>springside-core</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
        </dependency>

        <!-- Jackson -->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.module</groupId>
            <artifactId>jackson-module-jaxb-annotations</artifactId>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.datatype</groupId>
            <artifactId>jackson-datatype-joda</artifactId>
        </dependency>

        <!-- Common Utilitis -->
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-io</artifactId>
            <version>1.3.2</version>
        </dependency>
        <dependency>
            <groupId>com.google.guava</groupId>
            <artifactId>guava</artifactId>
        </dependency>

        <!-- Logback -->
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
        </dependency>
        <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-classic</artifactId>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>log4j-over-slf4j</artifactId>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>jcl-over-slf4j</artifactId>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>jul-to-slf4j</artifactId>
        </dependency>
        <dependency>
            <groupId>org.bgee.log4jdbc-log4j2</groupId>
            <artifactId>log4jdbc-log4j2-jdbc4</artifactId>
        </dependency>

        <!-- Code Generator -->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>

        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpclient</artifactId>
        </dependency>

        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
        </dependency>

    </dependencies>
</project>

建立com.wang.api.model的包，放LogModel.java，如下所示：

package com.wang.api.model;

import java.io.Serializable;
import java.util.Date;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@NoArgsConstructor
@AllArgsConstructor
public class LogModel implements Serializable {
    /**
     * 
     */
    private static final long serialVersionUID = 1L;
    /**
     * id
     */
    private String id;
    /**
     * 操作对象
     */
    private String entityId;
    /**
     * 操作人
     */
    private String userId;
    /**
     * 名称
     */
    private String name;
    /**
     * 内容
     */
    private String content;
    /**
     * 操作时间
     */
     private Date createTime;
    }

记得model一定要序列化。
然后我们再看看service层，com.wang.api.service包下建立LogService.java

package com.wang.api.service;

import com.wang.api.model.LogModel;


/**
 * 日志服务
 * @author wxe
 * @since 0.0.1
 */
public interface LogService {
    /**
     * 添加日志
     * @param log
     * @return
     */
    public LogModel add(LogModel logModel);
    /**
     * 删除日志
     * @param log
     * @return
     */
    public boolean delete(LogModel llogModelog);

}

2.3 spring-dubbo-provider
先看这个服务提供者的pom.xml

<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>
    <parent>
        <groupId>com.wang.dubbo</groupId>
        <artifactId>spring-dubbo</artifactId>
        <version>0.0.1-SNAPSHOT</version>
    </parent>
    <artifactId>spring-dubbo-provider</artifactId>
    <packaging>war</packaging>
    <name>spring-dubbo-provider</name>

    <dependencies>
        <dependency>
            <groupId>com.wang.dubbo</groupId>
            <artifactId>spring-dubbo-api</artifactId>
            <version>${dubbodemo.version}</version>
        </dependency>

        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>dubbo</artifactId>
            <version>2.8.4</version>
            <exclusions>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-core</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-beans</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-context</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-aop</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-expression</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-web</artifactId>
                </exclusion>
<!--                <exclusion> -->
<!--                    <groupId>org.javassist</groupId> -->
<!--                    <artifactId>javassist</artifactId> -->
<!--                </exclusion> -->
                <exclusion>
                    <groupId>log4j</groupId>
                    <artifactId>log4j</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.apache.httpcomponents</groupId>
                    <artifactId>httpclient</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.apache.httpcomponents</groupId>
                    <artifactId>httpcore</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

        <dependency>
            <groupId>com.101tec</groupId>
            <artifactId>zkclient</artifactId>
            <version>0.7</version>
            <exclusions>
                <exclusion>
                    <groupId>log4j</groupId>
                    <artifactId>log4j</artifactId>
                </exclusion>

                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-log4j12</artifactId>
                </exclusion>

            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.mortbay.jetty</groupId>
            <artifactId>jetty</artifactId>
            <version>6.1.24</version>
        </dependency>
        <dependency>
            <groupId>com.caucho</groupId>
            <artifactId>hessian</artifactId>
            <version>4.0.38</version>
        </dependency>
    </dependencies>
</project>

我这里建立的是一个web项目，所以先来介绍web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_1.xsd"
    version="3.1">

    <display-name>spring-dubbo-provider</display-name>

    <!-- Spring ApplicationContext配置文件的路径,可使用通配符，用于后面的Spring Context Loader -->
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>
            classpath*:applicationContext.xml
            classpath*:applicationContext-*.xml
        </param-value>
    </context-param>

    <!--Spring ApplicationContext 载入 -->
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>

    <!-- Filter 定义 -->
    <!-- Character Encoding filter -->
    <filter>
        <filter-name>encodingFilter</filter-name>
        <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>UTF-8</param-value>
        </init-param>
        <init-param>
            <param-name>forceEncoding</param-name>
            <param-value>true</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>encodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
    
    <!-- Support for HiddentHttpMethod -->
    <filter>
        <filter-name>hiddenHttpMethodFilter</filter-name>
        <filter-class>org.springframework.web.filter.HiddenHttpMethodFilter</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>hiddenHttpMethodFilter</filter-name>
        <servlet-name>springServlet</servlet-name>
    </filter-mapping>

    <!-- Spring MVC Servlet -->
    <servlet>
        <servlet-name>springServlet</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>/WEB-INF/spring-mvc.xml</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>springServlet</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>

    <session-config>
        <session-timeout>120</session-timeout>
    </session-config>
</web-app>

再来介绍下springmvc的配置文件，spring-mvc.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:p="http://www.springframework.org/schema/p" xmlns:c="http://www.springframework.org/schema/c" xmlns:context="http://www.springframework.org/schema/context"
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xmlns:aop="http://www.springframework.org/schema/aop"
    xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.1.xsd
        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">

    <!-- 自动扫描且只扫描@Controller -->
    <context:component-scan base-package="com.wang" use-default-filters="false">
        <context:include-filter type="annotation" expression="org.springframework.stereotype.Controller" />
        <context:include-filter type="annotation" expression="org.springframework.web.bind.annotation.ControllerAdvice" />
    </context:component-scan>
    
    <mvc:annotation-driven>
        <mvc:message-converters register-defaults="true">
            <bean class="org.springframework.http.converter.StringHttpMessageConverter" c:defaultCharset="UTF-8" />
        </mvc:message-converters>
    </mvc:annotation-driven>

    <!-- 定义JSP文件的位置 -->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver" 
        p:viewClass="org.springframework.web.servlet.view.JstlView"
        p:prefix="/WEB-INF/views/" 
        p:suffix=".jsp" />

    <!-- 容器默认的DefaultServletHandler处理 所有静态内容与无RequestMapping处理的URL -->
    <mvc:default-servlet-handler />
    
</beans>

然后来介绍下应用配置文件，主要来定义spring扫描除了controller注解的其他注解，applicationContext.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:util="http://www.springframework.org/schema/util"
    xmlns:aop="http://www.springframework.org/schema/aop" xmlns:task="http://www.springframework.org/schema/task"
    xsi:schemaLocation="
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task.xsd
        http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util.xsd
         ">

    <context:component-scan base-package="com.wang">
        <context:exclude-filter type="annotation" expression="org.springframework.stereotype.Controller" />
        <context:exclude-filter type="annotation" expression="org.springframework.web.bind.annotation.ControllerAdvice" />
    </context:component-scan>
    
</beans>

现在我们的服务提供者该提供服务了，就需要实现LogService.java，如下所示：

package com.wang.provider.service.impl;

import lombok.extern.slf4j.Slf4j;

import org.springframework.stereotype.Service;

import com.wang.api.model.LogModel;
import com.wang.api.service.LogService;


@Service("logService")
@Slf4j
public class LogServiceImpl implements LogService {

    public LogModel add(LogModel logModel) {
        log.info("哇，有人调用我的服务了哦！ :{}", logModel);
        return logModel;
    }

    public boolean delete(LogModel log) {
        // TODO Auto-generated method stub
        return false;
    }
}

现在服务实现好了，那么我们知道这个是要为别的客户端提供远程服务的，我们需要暴露这些服务，配置文件applicationContext-dubbo-provider.xml如下：

<?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
       ">
    <!-- 当前应用配置 -->
    <dubbo:application name="dubbo-provider" owner="dubbo" />
    <!-- 延迟暴露:delay="-1"延迟到spring初始化完成后，再暴露服务 -->
    <dubbo:provider delay="-1" />

    <!--使用 zookeeper 注册中心暴露服务，会在启动时检查依赖的服务是否可用，不可用时会抛出异常，阻止 Spring 初始化完成，以便上线时，能及早发现问题，默认 check="true" -->
    <dubbo:registry protocol="zookeeper" check="true" address="127.0.0.1:2181" />
    
    <!-- 服务提供者协议配置，服务线程池大小(固定大小) ，默认为100，threadpool：线程池类型，可选：fixed/cached ，默认fixed  -->
    <dubbo:protocol  name="dubbo"  port="20880" threads="200" accesslog="true" /> 
    <dubbo:protocol name="hessian" port="20881" threads="200" accesslog="true" />
    <!-- 服务提供者暴露服务,当一个接口有多种实现时，可以用group区分 -->
    <dubbo:service interface="com.wang.api.service.LogService" ref="logService" timeout="3000" loadbalance="random" protocol="dubbo"/>
</beans>

到这里为止，我们的服务提供者已经开发完毕了。后面来介绍下服务是消费者。
2.4 spring-dubbo-consumer
先来介绍pom.xml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/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>com.wang.dubbo</groupId>
        <artifactId>spring-dubbo</artifactId>
        <version>0.0.1-SNAPSHOT</version>
    </parent>
    <artifactId>spring-dubbo-consumer</artifactId>
    <packaging>war</packaging>
    <name>spring-dubbo-consumer</name>


    <dependencies>
        <dependency>
            <groupId>com.wang.dubbo</groupId>
            <artifactId>spring-dubbo-api</artifactId>
            <version>${dubbodemo.version}</version>
        </dependency>

        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>dubbo</artifactId>
            <version>2.8.4</version>
            <exclusions>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-core</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-beans</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-context</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-aop</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-expression</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-web</artifactId>
                </exclusion>
<!--                <exclusion> -->
<!--                    <groupId>org.javassist</groupId> -->
<!--                    <artifactId>javassist</artifactId> -->
<!--                </exclusion> -->
                <exclusion>
                    <groupId>log4j</groupId>
                    <artifactId>log4j</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.apache.httpcomponents</groupId>
                    <artifactId>httpclient</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.apache.httpcomponents</groupId>
                    <artifactId>httpcore</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

        <dependency>
            <groupId>com.101tec</groupId>
            <artifactId>zkclient</artifactId>
            <version>0.7</version>
            <exclusions>
                <exclusion>
                    <groupId>log4j</groupId>
                    <artifactId>log4j</artifactId>
                </exclusion>

                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-log4j12</artifactId>
                </exclusion>

            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.mortbay.jetty</groupId>
            <artifactId>jetty</artifactId>
            <version>6.1.24</version>
        </dependency>
        <dependency>
            <groupId>com.caucho</groupId>
            <artifactId>hessian</artifactId>
            <version>4.0.38</version>
        </dependency>
    </dependencies>

</project>

这个项目我建的也是一个web项目，所以介绍web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_1.xsd"
    version="3.1">

    <display-name>spring-dubbo-consumer</display-name>

    <!-- Spring ApplicationContext配置文件的路径,可使用通配符，用于后面的Spring Context Loader -->
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>
            classpath*:applicationContext.xml
            classpath*:applicationContext-*.xml
        </param-value>
    </context-param>

    <!--Spring ApplicationContext 载入 -->
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>
    
    <!-- Spring MVC Servlet -->
    <servlet>
        <servlet-name>springServlet</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>/WEB-INF/spring-mvc.xml</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>springServlet</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>

    <session-config>
        <session-timeout>120</session-timeout>
    </session-config>
</web-app>

再来看看spring-mvc.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:p="http://www.springframework.org/schema/p"
    xmlns:c="http://www.springframework.org/schema/c" xmlns:context="http://www.springframework.org/schema/context"
    xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:aop="http://www.springframework.org/schema/aop"
    xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.1.xsd
        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">

    <!-- 自动扫描且只扫描@Controller -->
    <context:component-scan base-package="com.wang" use-default-filters="false">
        <context:include-filter type="annotation" expression="org.springframework.stereotype.Controller" />
        <context:include-filter type="annotation" expression="org.springframework.web.bind.annotation.ControllerAdvice" />
    </context:component-scan>  

    <mvc:annotation-driven>
        <mvc:message-converters register-defaults="true">
            <bean class="org.springframework.http.converter.StringHttpMessageConverter"
                c:defaultCharset="UTF-8" />
        </mvc:message-converters>
    </mvc:annotation-driven>

    <!-- 定义JSP文件的位置 -->
    <bean
        class="org.springframework.web.servlet.view.InternalResourceViewResolver"
        p:viewClass="org.springframework.web.servlet.view.JstlView" p:prefix="/WEB-INF/views/"
        p:suffix=".jsp" />

    <!-- 容器默认的DefaultServletHandler处理 所有静态内容与无RequestMapping处理的URL -->
    <mvc:default-servlet-handler />
</beans>

然后看看相关的配置文件，主要用来扫描注解用的配置文件applicationContext.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:util="http://www.springframework.org/schema/util"
    xmlns:aop="http://www.springframework.org/schema/aop" xmlns:task="http://www.springframework.org/schema/task"
    xsi:schemaLocation="
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task.xsd
        http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util.xsd
         ">

    <context:component-scan base-package="com.wang">
        <context:exclude-filter type="annotation" expression="org.springframework.stereotype.Controller" />
        <context:exclude-filter type="annotation" expression="org.springframework.web.bind.annotation.ControllerAdvice" />
    </context:component-scan>
    
</beans>

既然我们想要使用服务，那么我们首先需要配置好使用服务的配置文件applicationContext-dubbo-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
       ">
    <!-- 当前应用配置 -->
    <dubbo:application name="dubbo-consumer" owner="dubbo" />
    <!-- 延迟暴露:delay="-1"延迟到spring初始化完成后，再暴露服务 -->
    <dubbo:provider delay="-1" />

    <!--使用 zookeeper 注册中心暴露服务，会在启动时检查依赖的服务是否可用，不可用时会抛出异常，阻止 Spring 初始化完成，以便上线时，能及早发现问题，默认 check="true" -->
    <dubbo:registry protocol="zookeeper" check="true" address="172.0.0.1:2181" />
    
    <!-- 服务提供者协议配置，服务线程池大小(固定大小) ，默认为100，threadpool：线程池类型，可选：fixed/cached ，默认fixed  -->
    <dubbo:protocol  name="dubbo"  port="20880" threads="200" accesslog="true" /> 
    <dubbo:protocol name="hessian" port="20881" threads="200" accesslog="true" />
    <!-- 远程服务 -->
    <dubbo:reference protocol="dubbo" check="false" id="logService" interface="com.wang.api.service.LogService" />
</beans>

好了，既然已经配置好服务了，我们来试试好用不。简历controller，

package com.wang.consumer;

import java.util.Date;
import java.util.UUID;

import org.mortbay.log.Log;
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.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;

import com.wang.api.model.LogModel;
import com.wang.api.service.LogService;

@Controller
@RequestMapping(value="/main")
public class MainController {
    
    @Autowired
    private LogService logService;
    
    @RequestMapping(value="/add",method = RequestMethod.GET)
    @ResponseBody
    public LogModel addLog(){
        LogModel logModel = new LogModel(UUID.randomUUID().toString(), "1111", "2222", "您好", "保存合同", new Date());
        Log.info("开始调用远程服务");
        LogModel newLog = logService.add(logModel);
        Log.info("调用服务完毕！{}",newLog.toString());
        return newLog;
    }

}

好了，点击http://localhost:8080/consumer/main/add，就可以看到打印出来的结果：

{"id":"748594b9-13f2-41dd-961a-880abf9d79dd","entityId":"1111","userId":"2222","name":"您好","content":"保存合同","createTime":1547103471019}