创建个性化的springboot starter，以集成dubbo为例

创建一个Packaging模式为pom的Maven Project:youyijiu-starter。pom.xml内容如下：

<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>youyijiu</groupId>
    <artifactId>youyijiu-starter</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>pom</packaging>
    <modules>
        <module>youyijiu-starter-common</module>
        <module>youyijiu-starter-dubbo</module>
    </modules>

    <!-- 基于spring boot 2.6.4 -->
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.6.4</version>
    </parent>

    <!-- 配置私有仓库发布地址 -->
    <distributionManagement>
        <repository>
            <id>releases</id>
            <url>http://192.168.0.123:7676/nexus/content/repositories/releases</url>
        </repository>
        <snapshotRepository>
            <id>snapshots</id>
            <url>http://192.168.0.123:7676/nexus/content/repositories/snapshots</url>
        </snapshotRepository>
    </distributionManagement>

    <!-- 各种项目通用属性 -->
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <skipTests>true</skipTests>
        <fastjson.version>1.2.3</fastjson.version>
        <dubbo.version>2.5.3</dubbo.version>
    </properties>

    <!-- Package as an executable jar -->
    <build>
        <plugins>
            <!-- Compiler 插件, 设定JDK版本 -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                    <encoding>UTF-8</encoding>
                    <showWarnings>true</showWarnings>
                </configuration>
            </plugin>

            <!--配置生成源码包 -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-source-plugin</artifactId>
                <executions>
                    <execution>
                        <id>attach-sources</id>
                        <goals>
                            <goal>jar</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
</project>

创建一个Packaging模式为jar的Maven Module:youyijiu-starter-dubbo，pom.xml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>
  <parent>
    <groupId>youyijiu</groupId>
    <artifactId>youyijiu-starter</artifactId>
    <version>0.0.1-SNAPSHOT</version>
  </parent>
  <groupId>youyijiu-starter-dubbo</groupId>
  <artifactId>youyijiu-starter-dubbo</artifactId>

  <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>youyijiu-starter-common</groupId>
            <artifactId>youyijiu-starter-common</artifactId>
            <version>0.0.1-SNAPSHOT</version>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>dubbo</artifactId>
            <version>${dubbo.version}</version>
            <exclusions>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>*</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>com.101tec</groupId>
            <artifactId>zkclient</artifactId>
            <version>0.9</version>
        </dependency>
        <dependency>
            <artifactId>slf4j-api</artifactId>
            <groupId>org.slf4j</groupId>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>${fastjson.version}</version>
        </dependency>
    </dependencies>
</project>

在youyijiu-starter-dubbo模块中创建自动配置类DubboAutoConfiguration，内容如下：

/**   
* @Title: DubboAutoConfiguration.java 
* @Package com.youyijiu.starter.dubbo 
* @author Jun.Yang 24696026@qq.com   
* @date 2022年8月13日 上午8:18:00    
*/
package com.youyijiu.starter.dubbo.autoconfigure;

import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.context.annotation.ImportResource;

/** 
 * @ClassName: DubboAutoConfiguration 
 * @Description: 加载Dubbo元数据配置，当属性配置中有 dubbo.zookeeper.address 和 dubbo.name 才会加载，
 *               当依赖该starter的项目配置有dubbo.zookeeper.address 和 dubbo.name 时，会扫描classpath
 *               下的dubbo-interfaces.xml文件加载dubbo的配置。
 * @author Jun.Yang 24696026@qq.com 
 * @date 2022年8月13日 上午8:18:00 
 *  
 */
@ConditionalOnProperty(name = {"dubbo.zookeeper.address","dubbo.name"})
@ImportResource({ "classpath:dubbo-interfaces.xml" })
public class DubboAutoConfiguration {

}

在youyijiu-starter-dubbo模块中的src/main/resources下创建META-INF目录，里面的spring.factories对于一个starter来说有着关键的作用，这里spring.factories的内容为：

org.springframework.boot.autoconfigure.EnableAutoConfiguration=com.youyijiu.starter.dubbo.autoconfigure.DubboAutoConfiguration

这样我们的dubbo就可以集成到springboot中了。使用的时候只需要引入如下依赖：

<dependency>
    <groupId>youyijiu-starter-dubbo</groupId>
    <artifactId>youyijiu-starter-dubbo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
</dependency>

接下来我们创建一个提供dubbo服务的模块来说明下，怎么使用这个youyijiu-starter-dubbo。创建一个Maven Module:youyijiu-test-dubbo-server，pom.xml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.youyijiu</groupId>
    <version>0.0.1-SNAPSHOT</version>
    <artifactId>youyijiu-test-dubbo-server</artifactId>

    <!-- 基于spring boot 2.6.4 -->
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.6.4</version>
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <skipTests>true</skipTests>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>youyijiu-starter-dubbo</groupId>
            <artifactId>youyijiu-starter-dubbo</artifactId>
            <version>0.0.1-SNAPSHOT</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.youyijiu</groupId>
            <artifactId>youyijiu-test-dubbo-api</artifactId>
            <version>0.0.1-SNAPSHOT</version>
        </dependency>
    </dependencies>

    <!-- Package as an executable jar -->
    <build>
        <plugins>

            <!-- Compiler 插件, 设定JDK版本 -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                    <encoding>UTF-8</encoding>
                    <showWarnings>true</showWarnings>
                </configuration>
            </plugin>

            <!--配置生成源码包 -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-source-plugin</artifactId>
                <executions>
                    <execution>
                        <id>attach-sources</id>
                        <goals>
                            <goal>jar</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
</project>

youyijiu-test-dubbo-server的application.properties中的内容为：

##web端口
server.port=8080

## dubbo配置
dubbo.name=youyijiu-test-dubbo-server
dubbo.zookeeper.address=127.0.0.1:2181
dubbo.group=test
dubbo.version=0.0.1
dubbo.timeout=20000

youyijiu-test-dubbo-server的dubbo-interfaces.xml中的内容为：

<?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:dubbo="http://code.alibabatech.com/schema/dubbo"
     xsi:schemaLocation="http://www.springframework.org/schema/beans
         http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
         http://code.alibabatech.com/schema/dubbo 
         http://code.alibabatech.com/schema/dubbo/dubbo.xsd">

    <dubbo:application name="${dubbo.name}"></dubbo:application>
    <!-- 使用zookeeper注册中心暴露服务地址 -->  
    <dubbo:registry address="${dubbo.zookeeper.address}" check="false" protocol="zookeeper"></dubbo:registry>
    <!-- 使用${}引用配置项 , 这里的dubboServer是在META-INF下的dubbo里的com.alibaba.dubbo.rpc.Filter中定义的-->
    <dubbo:provider port="-1" filter="dubboServer" retries="0" />

    <!-- 要暴露的服务接口  -->  
    <dubbo:service group="${dubbo.group}" version="${dubbo.version}" interface="com.youyijiu.dubbo.IDubboService" ref="dubboService"/>

    <!-- 消费方调用过程缺省拦截器，将拦截所有reference，这里的dubboClient是在META-INF下的dubbo里的com.alibaba.dubbo.rpc.Filter中定义的 -->
    <dubbo:consumer filter="dubboClient"/>

</beans>

这样，启动youyijiu-test-dubbo-server的时候，这个dubbo-interfaces.xml就已经把com.youyijiu.dubbo.IDubboService所提供的功能注册到zookeeper中去了。

接下来我们创建一个使用dubbo服务的模块。创建一个Maven Module:youyijiu-test-dubbo-client，pom.xml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.youyijiu</groupId>
    <version>0.0.1-SNAPSHOT</version>
    <artifactId>youyijiu-test-dubbo-client</artifactId>

    <!-- 基于spring boot 2.6.4 -->
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.6.4</version>
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <skipTests>true</skipTests>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>youyijiu-starter-dubbo</groupId>
            <artifactId>youyijiu-starter-dubbo</artifactId>
            <version>0.0.1-SNAPSHOT</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.youyijiu</groupId>
            <artifactId>youyijiu-test-dubbo-api</artifactId>
            <version>0.0.1-SNAPSHOT</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <!-- Package as an executable jar -->
    <build>
        <plugins>

            <!-- Compiler 插件, 设定JDK版本 -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.6.0</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                    <encoding>UTF-8</encoding>
                    <showWarnings>true</showWarnings>
                </configuration>
            </plugin>

            <!--配置生成源码包 -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-source-plugin</artifactId>
                <executions>
                    <execution>
                        <id>attach-sources</id>
                        <goals>
                            <goal>jar</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
</project>

youyijiu-test-dubbo-client的application.properties如下：

##web端口
##web端口
server.port=8090

## dubbo配置
dubbo.name=youyijiu-test-dubbo-client
dubbo.zookeeper.address=127.0.0.1:2181
dubbo.group=test
dubbo.version=0.0.1
dubbo.timeout=20000

youyijiu-test-dubbo-client的dubbo-interfaces.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:context="http://www.springframework.org/schema/context"
    xmlns:dubbo="http://code.alibabatech.com/schema/dubbo"
     xsi:schemaLocation="http://www.springframework.org/schema/beans
         http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
         http://code.alibabatech.com/schema/dubbo 
         http://code.alibabatech.com/schema/dubbo/dubbo.xsd">

    <dubbo:application name="${dubbo.name}"></dubbo:application>
    <!-- 使用zookeeper注册中心暴露服务地址 -->  
    <dubbo:registry address="${dubbo.zookeeper.address}" check="false" protocol="zookeeper"></dubbo:registry>
    <!-- 使用${}引用配置项 这里的dubboServer是在META-INF下的dubbo里的com.alibaba.dubbo.rpc.Filter中定义的-->
    <dubbo:provider port="-1" filter="dubboServer" retries="0" />

    <dubbo:reference id="IDubboService" interface="com.youyijiu.dubbo.IDubboService" group="${dubbo.group}" retries="0" version="${dubbo.version}" check="false" timeout="${dubbo.timeout}"/>

    <!-- 消费方调用过程缺省拦截器，将拦截所有reference , 这里的dubboClient是在META-INF下的dubbo里的com.alibaba.dubbo.rpc.Filter中定义的-->
    <dubbo:consumer filter="dubboClient"/>

</beans>

这样一个youyijiu-test-dubbo-client消费者就配置好了。IDubboService接口如下：

package com.youyijiu.dubbo;

/**
 * 
* @ClassName: IDubboService 
* @Description: TODO(这里用一句话描述这个类的作用) 
* @author Jun.Yang 24696026@qq.com 
* @date 2022年8月13日 上午9:57:06 
* 
* @param <R>
* @param <P>
 */
public interface IDubboService<R, P> {

    /**
     * 根据参数访问后返回结果
     * @param param
     * @return
     */
    R query(P param);

}

IDubboService的实现类DubboService如下：

/**   
* @Title: DubboService.java 
* @Package com.youyijiu.dubbo.service 
* @author Sean.Yang 908682620@qq.com   
* @date 2022年8月9日 下午2:57:53    
*/
package com.youyijiu.dubbo.service;

import org.springframework.stereotype.Service;

import com.youyijiu.dubbo.IDubboService;

/** 
 * @ClassName: DubboService 
 * @Description: TODO(这里用一句话描述这个类的作用) 
 * @author Sean.Yang 908682620@qq.com 
 * @date 2022年8月9日 下午2:57:53 
 *  
 */
@Service("dubboService")
public class DubboService implements IDubboService<String, String>{

    @Override
    public String query(String param) {
        StringBuilder sb = new StringBuilder(param);
        return sb.append(" ").append(param).toString();
    }


}

启动类：

package com.youyijiu.dubbo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.autoconfigure.dao.PersistenceExceptionTranslationAutoConfiguration;
import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
import org.springframework.context.annotation.ComponentScan;

import com.youyijiu.starter.common.util.SpringUtil;


/**
 * 
* @ClassName: Application 
* @Description: TODO(这里用一句话描述这个类的作用) 
* @author Jun.Yang 24696026@qq.com 
* @date 2022年8月13日 上午9:57:31 
*
 */
@EnableAutoConfiguration(exclude = { DataSourceAutoConfiguration.class,
        PersistenceExceptionTranslationAutoConfiguration.class })
@ComponentScan(basePackages = "com.youyijiu.dubbo")
public class Application {

    public static void main(String[] args) {
        SpringUtil.setApplicationContext(SpringApplication.run(
                Application.class, args));
    }
}

单元测试：

/**   
* @Title: DubboTest.java 
* @Package com.youyijiu.dubbo 
* @author Sean.Yang 908682620@qq.com   
* @date 2022年8月9日 下午4:17:55    
*/
package com.youyijiu.dubbo;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;


/** 
 * @ClassName: DubboTest 
 * @Description: TODO(这里用一句话描述这个类的作用) 
 * @author Sean.Yang 908682620@qq.com 
 * @date 2022年8月9日 下午4:17:55 
 *  
 */
@RunWith(SpringRunner.class)
@SpringBootTest(classes = Application.class)
public class DubboTest {

    @Autowired
    IDubboService<String, String> service;

    @Test
    public void dubboTest(){
        System.out.println(service.query("今天测试一下西"));
    }

}