文章目录

1. Dubbo快速入门代码编写
- 1.1 需求分析
- 1.2 项目和模块创建
- 1.3 导入相关依赖
- 1.4 编写提供服务的接口
- 1.5 编写调用服务的程序
- 1.6 安装dubbo-service（被依赖的模块需要安装）
- 1.7 配置Tomcat
- 1.8 启动测试
- 1.9 说明
- 1.10 改造dubbo-service：服务提供者
- 1.11 改造dubbo-web：服务消费者
- 1.12访问测试：需要重启2个Tomcat服务器（dubbo-web和dubbo-service）
2. 说明：源码下载

1. Dubbo – 分布式系统的相关概念（大型互联网项目架构目标集群和分布式架构演进）、Dubbo概述（Dubbo的概念和架构）、Dubbo快速入门（Zookepper的安装：注册中心中心）

2. Dubbo – Dubbo快速入门代码编写

3.Dubbo – dubbo-admin 的安装介绍使用

4. Dubbo – dubbo高级特性（序列化地址缓存超时与重试机制多版本：灰度发布负载均衡集群容错策略服务降级）

做这个案例需要安装Zookeeper（注册中心）

1. Dubbo快速入门代码编写

1.1 需求分析

1.2 项目和模块创建

创建一个dubbo-pro项目和他的2个模块，其中dubbo-service是普通模块，dubbo-web是web工程模块。

1.3 导入相关依赖

<?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-pro</artifactId><groupId>com.tian</groupId><version>1.0-SNAPSHOT</version></parent><modelVersion>4.0.0</modelVersion><packaging>war</packaging><artifactId>dubbo-web</artifactId><properties><spring.version>5.1.9.RELEASE</spring.version><dubbo.version>2.7.4.1</dubbo.version><zookeeper.version>4.0.0</zookeeper.version></properties><dependencies><!-- servlet3.0规范的坐标 --><dependency><groupId>javax.servlet</groupId><artifactId>javax.servlet-api</artifactId><version>3.1.0</version><scope>provided</scope></dependency><!--spring的坐标--><dependency><groupId>org.springframework</groupId><artifactId>spring-context</artifactId><version>${spring.version}</version></dependency><!--springmvc的坐标--><dependency><groupId>org.springframework</groupId><artifactId>spring-webmvc</artifactId><version>${spring.version}</version></dependency><!--日志--><dependency><groupId>org.slf4j</groupId><artifactId>slf4j-api</artifactId><version>1.7.21</version></dependency><dependency><groupId>org.slf4j</groupId><artifactId>slf4j-log4j12</artifactId><version>1.7.21</version></dependency><!--Dubbo的起步依赖，版本2.7之后统一为rg.apache.dubb --><dependency><groupId>org.apache.dubbo</groupId><artifactId>dubbo</artifactId><version>${dubbo.version}</version></dependency><!--ZooKeeper客户端实现 --><dependency><groupId>org.apache.curator</groupId><artifactId>curator-framework</artifactId><version>${zookeeper.version}</version></dependency><!--ZooKeeper客户端实现 --><dependency><groupId>org.apache.curator</groupId><artifactId>curator-recipes</artifactId><version>${zookeeper.version}</version></dependency><!--公共接口模块--><dependency><groupId>com.tian</groupId><artifactId>dubbo-service</artifactId><version>1.0-SNAPSHOT</version></dependency></dependencies>
</project>

<?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-pro</artifactId><groupId>com.tian</groupId><version>1.0-SNAPSHOT</version></parent><modelVersion>4.0.0</modelVersion><artifactId>dubbo-service</artifactId><properties><spring.version>5.1.9.RELEASE</spring.version><dubbo.version>2.7.4.1</dubbo.version><zookeeper.version>4.0.0</zookeeper.version></properties><dependencies><!-- servlet3.0规范的坐标 --><dependency><groupId>javax.servlet</groupId><artifactId>javax.servlet-api</artifactId><version>3.1.0</version><scope>provided</scope></dependency><!--spring的坐标--><dependency><groupId>org.springframework</groupId><artifactId>spring-context</artifactId><version>${spring.version}</version></dependency><!--springmvc的坐标--><dependency><groupId>org.springframework</groupId><artifactId>spring-webmvc</artifactId><version>${spring.version}</version></dependency><!--日志--><dependency><groupId>org.slf4j</groupId><artifactId>slf4j-api</artifactId><version>1.7.21</version></dependency><dependency><groupId>org.slf4j</groupId><artifactId>slf4j-log4j12</artifactId><version>1.7.21</version></dependency><!--Dubbo的起步依赖，版本2.7之后统一为rg.apache.dubb --><dependency><groupId>org.apache.dubbo</groupId><artifactId>dubbo</artifactId><version>${dubbo.version}</version></dependency><!--ZooKeeper客户端实现 --><dependency><groupId>org.apache.curator</groupId><artifactId>curator-framework</artifactId><version>${zookeeper.version}</version></dependency><!--ZooKeeper客户端实现 --><dependency><groupId>org.apache.curator</groupId><artifactId>curator-recipes</artifactId><version>${zookeeper.version}</version></dependency></dependencies></project>

1.4 编写提供服务的接口

DubboService.java

package com.tian.service;public interface DubboService {public String helloDubbo();
}

DubboServiceImpl.java

package com.tian.service.impl;import com.tian.service.DubboService;
import org.springframework.stereotype.Service;@Service
public class DubboServiceImpl implements DubboService {@Overridepublic String helloDubbo() {return "Hello Dubbo";}
}

配置日志文件和包扫描：

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"xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd"><context:component-scan base-package="com.tian.service"/>
</beans>

log4j.properties

# DEBUG < INFO < WARN < ERROR < FATAL
# Global logging configuration
log4j.rootLogger=info, stdout,file
# My logging configuration...
#log4j.logger.com.tocersoft.school=DEBUG
#log4j.logger.net.sf.hibernate.cache=debug
## Console output...
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%5p %d %C: %m%nlog4j.appender.file=org.apache.log4j.FileAppender
log4j.appender.file.File=../logs/iask.log
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss}  %l  %m%n

1.5 编写调用服务的程序

DubboController.java

package com.tian.controller;import com.tian.service.DubboService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;@RestController
@RequestMapping("/dubbo")
public class DubboController {@Autowiredprivate DubboService dubboService;@RequestMapping("/hello")public String helloDubbo() {return dubboService.helloDubbo();}
}

springmvc.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 https://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/mvc https://www.springframework.org/schema/mvc/spring-mvc.xsd"><mvc:annotation-driven/><context:component-scan base-package="com.tian.controller"/>
</beans>

log4j.properties

# DEBUG < INFO < WARN < ERROR < FATAL
# Global logging configuration
log4j.rootLogger=info, stdout,file
# My logging configuration...
#log4j.logger.com.tocersoft.school=DEBUG
#log4j.logger.net.sf.hibernate.cache=debug
## Console output...
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%5p %d %C: %m%nlog4j.appender.file=org.apache.log4j.FileAppender
log4j.appender.file.File=../logs/iask.log
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss}  %l  %m%n

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"><!-- spring --><context-param><param-name>contextConfigLocation</param-name><param-value>classpath*:spring/applicationContext.xml</param-value></context-param><listener><listener-class>org.springframework.web.context.ContextLoaderListener</listener-class></listener><!-- Springmvc --><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:spring/springmvc.xml</param-value></init-param></servlet><servlet-mapping><servlet-name>springmvc</servlet-name><url-pattern>*.do</url-pattern></servlet-mapping>
</web-app>

1.6 安装dubbo-service（被依赖的模块需要安装）

说明：我安装了一个Maven Helper的

1.7 配置Tomcat

1.8 启动测试

http://localhost:8080/dubbo/hello.do

1.9 说明

现在的架构：虽然现在模块拆分了，但是并不是微服务架构，因为service模块（jar包）不可以作为独立的模块提供服务。

我们还需要把他改装成为这种结构

1.10 改造dubbo-service：服务提供者

1）把dubbo-service的打包方式改为war

2）改造 DubboServiceImpl

package com.tian.service.impl;import com.tian.service.DubboService;
import org.apache.dubbo.config.annotation.Service;/*** 现在不需要 @Service 注解了, @Service注解的作用是把该类的对象创建出来, 放到IOC中*//*注意现在的包是org.apache.dubbo和上面是不同的, 这个注解的作用是将这个类提供的方法（服务）对外发布. 将访问的地址（ip + 端口号 + 路径） 注册到注册中心*/
@Service
public class DubboServiceImpl implements DubboService {@Overridepublic String helloDubbo() {return "Hello Dubbo";}
}

3）配置注册中心地址

<?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"><!--    <context:component-scan base-package="com.tian.service"/>--><!--    配置项目的名称 唯一--><dubbo:application name="dubbo-service"/><!--    配置注册中心的地址--><dubbo:registry address="zookeeper://192.168.135.130:2181"/><!--    配置dubbo包扫描--><dubbo:annotation package="com.tian.service.impl"/>
</beans>

4）把dubbo-service改造成web项目

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"><!-- spring --><context-param><param-name>contextConfigLocation</param-name><param-value>classpath*:spring/applicationContext.xml</param-value></context-param><listener><listener-class>org.springframework.web.context.ContextLoaderListener</listener-class></listener>
</web-app><!--    去掉springMVC相关配置-->

5）配置Tomcat 启动服务

我把这个端口设置成为了9000

如果启动没有报错就证明改造成功了。

1.11 改造dubbo-web：服务消费者

1）建立一个模块，里面存放公告的接口，然后安装该模块

2）dubbo-service和dubbo-web引入该模块

然后删去dubbo-web引入dubbo-service的依赖：

3）配置注册中心

<?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" 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://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/mvc https://www.springframework.org/schema/mvc/spring-mvc.xsd http://dubbo.apache.org/schema/dubbo http://dubbo.apache.org/schema/dubbo/dubbo.xsd"><mvc:annotation-driven/><context:component-scan base-package="com.tian.controller"/><!--    配置项目的名称 唯一--><dubbo:application name="dubbo-web"><dubbo:parameter key="qos.port" value="33333"/></dubbo:application><!--    配置注册中心的地址--><dubbo:registry address="zookeeper://192.168.135.130:2181"/><!--    配置dubbo包扫描--><dubbo:annotation package="com.tian.controller"/>
</beans>

4）改造web.xml

删去了spring相关的配置，留下了SpringMVC相关配置。

<?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"><!-- Springmvc --><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:spring/springmvc.xml</param-value></init-param></servlet><servlet-mapping><servlet-name>springmvc</servlet-name><url-pattern>*.do</url-pattern></servlet-mapping>
</web-app>

5）完成对DubboController的改造