SpringBoot2 配置多數據源，整合MybatisPlus增強插件

本文源碼：GitHub·點這里 || GitEE·點這里

一、項目案例簡介

1、多數據簡介

實際的項目中，經常會用到不同的數據庫以滿足項目的實際需求。隨著業務的并發量的不斷增加，一個項目使用多個數據庫：主從復制、讀寫分離、分布式數據庫等方式，越來越常見。

2、MybatisPlus簡介

MyBatis-Plus（簡稱 MP）是一個MyBatis的增強工具，在MyBatis的基礎上只做增強不做改變，為簡化開發、提高效率而生。

插件特點

無代碼侵入：只做增強不做改變，引入它不會對現有工程產生影響。
強大的 CRUD 操作：通過少量配置即可實現單表大部分 CRUD 操作滿足各類使用需求。
支持 Lambda 形式調用：通過 Lambda 表達式，方便的編寫各類查詢條件。
支持主鍵自動生成：可自由配置，解決主鍵問題。
內置代碼生成器：采用代碼或者 Maven 插件可快速生成各層代碼。
內置分頁插件：基于 MyBatis 物理分頁，開發者無需關心具體操作。
內置性能分析插件：可輸出 Sql 語句以及其執行時間。

二、多數據源案例

1、項目結構

注意：mapper層和mapper.xml層分別放在不同目錄下，以便mybatis掃描加載。

2、多數據源配置

spring:
  # 數據源配置
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource
    admin-data:
      driverClassName: com.mysql.jdbc.Driver
      dbUrl: jdbc:mysql://127.0.0.1:3306/cloud-admin-data?useUnicode=true&characterEncoding=UTF8&zeroDateTimeBehavior=convertToNull&useSSL=false
      username: root
      password: 123
      initialSize: 20
      maxActive: 100
      minIdle: 20
      maxWait: 60000
      poolPreparedStatements: true
      maxPoolPreparedStatementPerConnectionSize: 30
      timeBetweenEvictionRunsMillis: 60000
      minEvictableIdleTimeMillis: 30000
      maxEvictableIdleTimeMillis: 60000
      validationQuery: SELECT 1 FROM DUAL
      testOnBorrow: false
      testOnReturn: false
      testWhileIdle: true
      connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000
      filters: stat,wall
    user-data:
      driverClassName: com.mysql.jdbc.Driver
      dbUrl: jdbc:mysql://127.0.0.1:3306/cloud-user-data?useUnicode=true&characterEncoding=UTF8&zeroDateTimeBehavior=convertToNull&useSSL=false
      username: root
      password: 123
      initialSize: 20
      maxActive: 100
      minIdle: 20
      maxWait: 60000
      poolPreparedStatements: true
      maxPoolPreparedStatementPerConnectionSize: 30
      timeBetweenEvictionRunsMillis: 60000
      minEvictableIdleTimeMillis: 30000
      maxEvictableIdleTimeMillis: 60000
      validationQuery: SELECT 1 FROM DUAL
      testOnBorrow: false
      testOnReturn: false
      testWhileIdle: true
      connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000
      filters: stat,wall

這里參數的形式是多樣的，只需要配置參數掃描即可。

3、參數掃描類

@Component
@ConfigurationProperties(prefix = "spring.datasource.admin-data")
public class DruidOneParam {
    private String dbUrl;
    private String username;
    private String password;
    private String driverClassName;
    private int initialSize;
    private int maxActive;
    private int minIdle;
    private int maxWait;
    private boolean poolPreparedStatements;
    private int maxPoolPreparedStatementPerConnectionSize;
    private int timeBetweenEvictionRunsMillis;
    private int minEvictableIdleTimeMillis;
    private int maxEvictableIdleTimeMillis;
    private String validationQuery;
    private boolean testWhileIdle;
    private boolean testOnBorrow;
    private boolean testOnReturn;
    private String filters;
    private String connectionProperties;
    // 省略 GET 和 SET
}

4、配置Druid連接池

@Configuration
@MapperScan(basePackages = {"com.data.source.mapper.one"},sqlSessionTemplateRef = "sqlSessionTemplateOne")
public class DruidOneConfig {
    private static final Logger LOGGER = LoggerFactory.getLogger(DruidOneConfig.class) ;
    @Resource
    private DruidOneParam druidOneParam ;
    @Bean("dataSourceOne")
    public DataSource dataSourceOne () {
        DruidDataSource datasource = new DruidDataSource();
        datasource.setUrl(druidOneParam.getDbUrl());
        datasource.setUsername(druidOneParam.getUsername());
        datasource.setPassword(druidOneParam.getPassword());
        datasource.setDriverClassName(druidOneParam.getDriverClassName());
        datasource.setInitialSize(druidOneParam.getInitialSize());
        datasource.setMinIdle(druidOneParam.getMinIdle());
        datasource.setMaxActive(druidOneParam.getMaxActive());
        datasource.setMaxWait(druidOneParam.getMaxWait());
        datasource.setTimeBetweenEvictionRunsMillis(druidOneParam.getTimeBetweenEvictionRunsMillis());
        datasource.setMinEvictableIdleTimeMillis(druidOneParam.getMinEvictableIdleTimeMillis());
        datasource.setMaxEvictableIdleTimeMillis(druidOneParam.getMaxEvictableIdleTimeMillis());
        datasource.setValidationQuery(druidOneParam.getValidationQuery());
        datasource.setTestWhileIdle(druidOneParam.isTestWhileIdle());
        datasource.setTestOnBorrow(druidOneParam.isTestOnBorrow());
        datasource.setTestOnReturn(druidOneParam.isTestOnReturn());
        datasource.setPoolPreparedStatements(druidOneParam.isPoolPreparedStatements());
        datasource.setMaxPoolPreparedStatementPerConnectionSize(druidOneParam.getMaxPoolPreparedStatementPerConnectionSize());
        try {
            datasource.setFilters(druidOneParam.getFilters());
        } catch (Exception e) {
            LOGGER.error("druid configuration initialization filter", e);
        }
        datasource.setConnectionProperties(druidOneParam.getConnectionProperties());
        return datasource;
    }
    @Bean
    public SqlSessionFactory sqlSessionFactoryOne() throws Exception{
        SqlSessionFactoryBean factory = new SqlSessionFactoryBean();
        ResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();
        factory.setDataSource(dataSourceOne());
        factory.setMapperLocations(resolver.getResources("classpath*:/dataOneMapper/*.xml"));
        return factory.getObject();
    }
    @Bean(name="transactionManagerOne")
    public DataSourceTransactionManager transactionManagerOne(){
        return  new DataSourceTransactionManager(dataSourceOne());
    }
    @Bean(name = "sqlSessionTemplateOne")
    public SqlSessionTemplate sqlSessionTemplateOne() throws Exception {
        return new SqlSessionTemplate(sqlSessionFactoryOne());
    }
}

注意事項

• MapperScan 在指定數據源上配置;
• SqlSessionFactory 配置掃描的Mapper.xml地址 ;
• DataSourceTransactionManager 配置該數據源的事務;
• 兩個數據源的配置手法相同，不贅述 ;

5、操作案例

• 數據源一：簡單查詢

  @Service
  public class AdminUserServiceImpl implements AdminUserService {
  @Resource
  private AdminUserMapper adminUserMapper ;
  @Override
  public AdminUser selectByPrimaryKey (Integer id) {
      return adminUserMapper.selectByPrimaryKey(id) ;
  }
  }

• 數據源二：事務操作

  @Service
  public class UserBaseServiceImpl implements UserBaseService {
  @Resource
  private UserBaseMapper userBaseMapper ;
  @Override
  public UserBase selectByPrimaryKey(Integer id) {
      return userBaseMapper.selectByPrimaryKey(id);
  }
  // 使用指定數據源的事務
  @Transactional(value = "transactionManagerTwo")
  @Override
  public void insert(UserBase record) {
      // 這里數據寫入失敗
      userBaseMapper.insert(record) ;
      // int i = 1/0 ;
  }
  }

  注意：這里的需要指定該數據源配置的事務管理器。

三、MybatisPlus案例

1、核心依賴

<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus-boot-starter</artifactId>
    <version>3.0.7.1</version>
    <exclusions>
        <exclusion>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-generator</artifactId>
        </exclusion>
    </exclusions>
</dependency>
<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus</artifactId>
    <version>3.0.7.1</version>
</dependency>

2、配置文件

mybatis-plus:
  mapper-locations: classpath*:/mapper/*.xml
  typeAliasesPackage: com.digital.market.*.entity
  global-config:
    db-config:
      id-type: AUTO
      field-strategy: NOT_NULL
      logic-delete-value: -1
      logic-not-delete-value: 0
    banner: false
  configuration:
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl
    map-underscore-to-camel-case: true
    cache-enabled: false
    call-setters-on-nulls: true
    jdbc-type-for-null: 'null'

3、分層配置

mapper層
UserBaseMapper extends BaseMapper<UserBase>
實現層
UserBaseServiceImpl extends ServiceImpl<UserBaseMapper,UserBase> implements UserBaseService
接口層
UserBaseService extends IService<UserBase>

4、mapper.xml文件

<mapper namespace="com.plus.batis.mapper.UserBaseMapper" >
  <resultMap id="BaseResultMap" type="com.plus.batis.entity.UserBase" >
    <id column="id" property="id" jdbcType="INTEGER" />
    <result column="user_name" property="userName" jdbcType="VARCHAR" />
    <result column="pass_word" property="passWord" jdbcType="VARCHAR" />
    <result column="phone" property="phone" jdbcType="VARCHAR" />
    <result column="email" property="email" jdbcType="VARCHAR" />
    <result column="create_time" property="createTime" jdbcType="TIMESTAMP" />
    <result column="update_time" property="updateTime" jdbcType="TIMESTAMP" />
    <result column="state" property="state" jdbcType="INTEGER" />
  </resultMap>
  <sql id="Base_Column_List" >
    id, user_name, pass_word, phone, email, create_time, update_time, state
  </sql>
  <select id="selectByParam" parameterType="com.plus.batis.entity.QueryParam" resultMap="BaseResultMap">
    select * from hc_user_base
  </select>
</mapper>

注意事項

BaseMapper中的方法都已默認實現；這里也可以自定義實現一些自己的方法。

5、演示接口

@RestController
@RequestMapping("/user")
public class UserBaseController {
    private static final Logger LOGGER = LoggerFactory.getLogger(UserBaseController.class) ;
    @Resource
    private UserBaseService userBaseService ;
    @RequestMapping("/info")
    public UserBase getUserBase (){
        return userBaseService.getById(1) ;
    }
    @RequestMapping("/queryInfo")
    public String queryInfo (){
        UserBase userBase1 = userBaseService.getOne(new QueryWrapper<UserBase>().orderByDesc("create_time")) ;
        LOGGER.info("倒敘取值：{}",userBase1.getUserName());
        Integer count = userBaseService.count() ;
        LOGGER.info("查詢總數：{}",count);
        UserBase userBase2 = new UserBase() ;
        userBase2.setId(1);
        userBase2.setUserName("spring");
        boolean resFlag = userBaseService.saveOrUpdate(userBase2) ;
        LOGGER.info("保存更新：{}",resFlag);
        Map<String, Object> listByMap = new HashMap<>() ;
        listByMap.put("state","0") ;
        Collection<UserBase> listMap = userBaseService.listByMap(listByMap) ;
        LOGGER.info("ListByMap查詢：{}",listMap);
        boolean removeFlag = userBaseService.removeById(3) ;
        LOGGER.info("刪除數據：{}",removeFlag);
        return "success" ;
    }
    @RequestMapping("/queryPage")
    public IPage<UserBase> queryPage (){
        QueryParam param = new QueryParam() ;
        param.setPage(1);
        param.setPageSize(10);
        param.setUserName("cicada");
        param.setState(0);
        return userBaseService.queryPage(param) ;
    }
    @RequestMapping("/pageHelper")
    public PageInfo<UserBase> pageHelper (){
        return userBaseService.pageHelper(new QueryParam()) ;
    }
}

這里pageHelper方法是使用PageHelper插件自定義的方法。

四、源代碼地址

GitHub·地址
https://github.com/cicadasmile/middle-ware-parent
GitEE·地址
https://gitee.com/cicadasmile/middle-ware-parent