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mapperscan掃描多個包_SpringBoot和Mybatis配置多資料源連接配接多個資料庫

SpringBoot和Mybatis配置多資料源連接配接多個資料庫

mapperscan掃描多個包_SpringBoot和Mybatis配置多資料源連接配接多個資料庫

目前業界操作資料庫的架構一般是

Mybatis

,但在很多業務場景下,我們需要在一個工程裡配置多個資料源來實作業務邏輯。在

SpringBoot

中也可以實作多資料源并配合

Mybatis

架構編寫xml檔案來執行SQL。在

SpringBoot

中,配置多資料源的方式十分便捷,

下面開始上代碼:

  • pom.xml

    檔案中需要添加一些依賴
<!-- Spring Boot Mybatis 依賴 -->
<dependency>
  <groupId>org.mybatis.spring.boot</groupId>
  <artifactId>mybatis-spring-boot-starter</artifactId>
  <version>1.2.0</version>
</dependency>

<!-- MySQL 連接配接驅動依賴 -->
<dependency>
  <groupId>mysql</groupId>
  <artifactId>mysql-connector-java</artifactId>
  <version>5.1.39</version>
</dependency>

<!-- Druid 資料連接配接池依賴 -->
<dependency>
  <groupId>com.alibaba</groupId>
  <artifactId>druid</artifactId>
  <version>1.0.18</version>
</dependency>
           
  • application.properties 配置兩個資料源配置
# master 資料源配置
master.datasource.url=jdbc:mysql://localhost:3306/springbootdb?useUnicode=true&characterEncoding=utf8
master.datasource.username=root
master.datasource.password=321
master.datasource.driverClassName=com.mysql.jdbc.Driver

# second 資料源配置
second.datasource.url=jdbc:mysql://localhost:3306/springbootdb_second?useUnicode=true&characterEncoding=utf8
second.datasource.username=root
second.datasource.password=321
second.datasource.driverClassName=com.mysql.jdbc.Driver
           
  • 資料源配置
多資料源配置的時候注意,必須要有一個主資料源,即

MasterDataSourceConfig

配置
  • @Primary 标志這個 Bean 如果在多個同類 Bean 候選時,該 Bean 優先被考慮。「多資料源配置的時候注意,必須要有一個主資料源,用 @Primary 标志該 Bean
  • @MapperScan 掃描 Mapper 接口并容器管理,包路徑精确到 master,為了和下面 cluster 資料源做到精确區分
  • @Value 擷取全局配置檔案 application.properties 的 kv 配置,并自動裝配sqlSessionFactoryRef 表示定義了 key ,表示一個唯一 SqlSessionFactory 執行個體

MasterDataSourceConfig

的代碼:

@Configuration
// 掃描 Mapper 接口并容器管理
@MapperScan(basePackages = MasterDataSourceConfig.PACKAGE, sqlSessionFactoryRef = "masterSqlSessionFactory")
public class MasterDataSourceConfig {

    // 精确到 master 目錄,以便跟其他資料源隔離
    static final String PACKAGE = "org.spring.springboot.dao.master";
    static final String MAPPER_LOCATION = "classpath:mapper/master/*.xml";

    @Value("${master.datasource.url}")
    private String url;

    @Value("${master.datasource.username}")
    private String user;

    @Value("${master.datasource.password}")
    private String password;

    @Value("${master.datasource.driverClassName}")
    private String driverClass;

    @Bean(name = "masterDataSource")
    @Primary
    public DataSource masterDataSource() {
        DruidDataSource dataSource = new DruidDataSource();
        dataSource.setDriverClassName(driverClass);
        dataSource.setUrl(url);
        dataSource.setUsername(user);
        dataSource.setPassword(password);
        return dataSource;
    }

    @Bean(name = "masterTransactionManager")
    @Primary
    public DataSourceTransactionManager masterTransactionManager() {
        return new DataSourceTransactionManager(masterDataSource());
    }

    @Bean(name = "masterSqlSessionFactory")
    @Primary
    public SqlSessionFactory masterSqlSessionFactory(@Qualifier("masterDataSource") DataSource masterDataSource)
            throws Exception {
        final SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean();
        sessionFactory.setDataSource(masterDataSource);
        sessionFactory.setMapperLocations(new PathMatchingResourcePatternResolver()
                .getResources(MasterDataSourceConfig.MAPPER_LOCATION));
        return sessionFactory.getObject();
    }
}
           

第二個資料源

SecondDataSourceConfig

的配置如下:

@Configuration
// 掃描 Mapper 接口并容器管理
@MapperScan(basePackages = SecondDataSourceConfig.PACKAGE, sqlSessionFactoryRef = "secondSqlSessionFactory")
public class SecondDataSourceConfig {

    // 精确到 cluster 目錄,以便跟其他資料源隔離
    static final String PACKAGE = "com.springboot.dao.second";
    static final String MAPPER_LOCATION = "classpath:mapper/second/*.xml";

    @Value("${second.datasource.url}")
    private String url;

    @Value("${second.datasource.username}")
    private String user;

    @Value("${second.datasource.password}")
    private String password;

    @Value("${second.datasource.driverClassName}")
    private String driverClass;

    @Bean(name = "secondDataSource")
    public DataSource clusterDataSource() {
        DruidDataSource dataSource = new DruidDataSource();
        dataSource.setDriverClassName(driverClass);
        dataSource.setUrl(url);
        dataSource.setUsername(user);
        dataSource.setPassword(password);
        return dataSource;
    }

    @Bean(name = "secondTransactionManager")
    public DataSourceTransactionManager clusterTransactionManager() {
        return new DataSourceTransactionManager(clusterDataSource());
    }

    @Bean(name = "secondSqlSessionFactory")
    public SqlSessionFactory clusterSqlSessionFactory(@Qualifier("secondDataSource") DataSource clusterDataSource)
            throws Exception {
        final SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean();
        sessionFactory.setDataSource(clusterDataSource);
        sessionFactory.setMapperLocations(new PathMatchingResourcePatternResolver()
                .getResources(SecondDataSourceConfig.MAPPER_LOCATION));
        return sessionFactory.getObject();
    }
}
           

到此,不同的資料源配置就已經完成,剩下的隻需要将将

Mybatis

的xml檔案和

DAO

層的接口寫好,并在

Service

層注入,直接使用就行。

Service

層的代碼:

@Service
public class UserServiceImpl implements UserService {

    @Autowired
    private UserDao userDao;
    @Autowired
    private SchoolDao schoolDao;

    public UserVo getUser(Long id) {
        UserVo userVo = userDao.findById(id);
        SchoolVo schoolVo = schoolDao.findByName("清華");
        userVo.setSchoolVo(schoolVo);
        return userVo;
    }

}
           

Mybatis的xml檔案

UserDao.xml

SchoolDao.xml

的内容:

UserDao.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
<mapper namespace="com.springboot.dao.master.UserDao">
    <resultMap id="BaseResultMap" type="com.springboot.vo.UserVo">
        <result column="id" property="id" />
        <result column="user_name" property="userName" />
    </resultMap>

    <sql id="Base_Column_List">
        id, user_name
    </sql>

    <select id="findById" resultMap="BaseResultMap" parameterType="java.lang.Long">
        select
            <include refid="Base_Column_List" />
        from
            user
        where
            id = #{id}
    </select>
</mapper>
           

SchoolDao.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
<mapper namespace="com.springboot.dao.second.SchoolDao">
    <resultMap id="BaseResultMap" type="com.springboot.vo.SchoolVo">
        <result column="id" property="id" />
        <result column="school_name" property="schoolName" />
        <result column="school_describe" property="schoolDescribe" />
    </resultMap>

    <sql id="Base_Column_List">
        id, school_name, school_describe
    </sql>

    <select id="findByName" resultMap="BaseResultMap" parameterType="java.lang.String">
        select
            <include refid="Base_Column_List" />
        from
            school
        where
            school_name = #{schoolName}
    </select>

</mapper>
           

TestController

@Controller
@RequestMapping(value = "/api/v1/test")
public class TestController {

    @Autowired
    private UserService userService;

    @RequestMapping(value = "/getUser")
    @ResponseBody
    public UserVo getUser(@RequestParam(value = "id") Long id) {
        return userService.getUser(id);
    }

}
           

建立資料庫和表SQL:

CREATE DATABASE springbootdb;

CREATE DATABASE springbootdb_second;

CREATE TABLE `user` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT COMMENT '使用者編号',
  `user_name` varchar(25) DEFAULT NULL COMMENT '使用者名稱',
  `description` varchar(25) DEFAULT NULL COMMENT '描述',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8

CREATE TABLE `school` (
  `id` bigint(20) NOT NULL,
  `school_name` varchar(64) DEFAULT NULL COMMENT '學校名',
  `school_describe` varchar(128) DEFAULT NULL COMMENT '學校描述',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8

insert into `springbootdb`.`user` ( `user_name`, `description`) values ( 'shuai', 'so handsome');

insert into `springbootdb_second`.`school` ( `id`, `school_name`, `school_describe`) values ( '1', '清華', '自強不息,厚德載物');
           

建立好資料後,整個工程的機構如下:

啟動程式,在浏覽器輸入:http://localhost:8080/api/v1/test/getUser?id=1即可傳回結果。

mapperscan掃描多個包_SpringBoot和Mybatis配置多資料源連接配接多個資料庫
github位址:Spring Boot 教程、技術棧、示例代碼

http://weixin.qq.com/r/fSj44CfE7HqTrWOD931v (二維碼自動識别)

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