Springboot集成mybatis实现多数据源配置详解流程-Java开发

在日常开发中，若遇到多个数据源的需求，怎么办呢？通过springboot集成mybatis实现多数据源配置，简单尝试一下，文中通过示例代码介绍的非常详细，对大家的学习或者工作具有一定的参考学习价值，需要的朋友们下面随着小编来一起学习学习吧

新建springboot工程，引入web、mysql、mybatis依赖

		<dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.2.2</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>

在application.properties中配置多数据源

spring.datasource.primary.jdbc-url=jdbc:mysql://localhost:3306/ds0
spring.datasource.primary.username=root
spring.datasource.primary.password=root
spring.datasource.primary.driver-class-name=com.mysql.cj.jdbc.Driver

spring.datasource.secondary.jdbc-url=jdbc:mysql://localhost:3306/ds1
spring.datasource.secondary.username=root
spring.datasource.secondary.password=root
spring.datasource.secondary.driver-class-name=com.mysql.cj.jdbc.Driver

多数据源配置与单个数据源配置不同点在于，spring.datasource之后多了一个数据源名称primary/secondary用来区分不同的数据源；

初始化数据源

新建一个配置类，用来加载多个数据源完成初始化。

@Configuration
public class DataSourceConfiguration {
    @Primary
    @Bean
    @ConfigurationProperties(prefix = "spring.datasource.primary")
    public DataSource primaryDataSource() {
        return DataSourceBuilder.create().build();
    }
    @Bean
    @ConfigurationProperties(prefix = "spring.datasource.secondary")
    public DataSource secondaryDataSource() {
        return DataSourceBuilder.create().build();
    }
}

通过@ConfigurationProperties就可以知道这两个数据源分别加载了spring.datasource.primary.*和spring.datasource.secondary.*的配置。@Primary注解指定了主数据源，当不指定数据源时，就会使用该主数据源。

mybatis配置

@Configuration
@MapperScan(
        basePackages = "com*.primary",
        sqlSessionFactoryRef = "sqlSessionFactoryPrimary",
        sqlSessionTemplateRef = "sqlSessionTemplatePrimary")
public class PrimaryConfig {
    private DataSource primaryDataSource;
    public PrimaryConfig(@Qualifier("primaryDataSource") DataSource primaryDataSource) {
        this.primaryDataSource = primaryDataSource;
    }
    @Bean
    public SqlSessionFactory sqlSessionFactoryPrimary() throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(primaryDataSource);
        return bean.getObject();
    }
    @Bean
    public SqlSessionTemplate sqlSessionTemplatePrimary() throws Exception {
        return new SqlSessionTemplate(sqlSessionFactoryPrimary());
    }
}

@Configuration
@MapperScan(
        basePackages = "com.*.secondary",
        sqlSessionFactoryRef = "sqlSessionFactorySecondary",
        sqlSessionTemplateRef = "sqlSessionTemplateSecondary")
public class SecondaryConfig {
    private DataSource secondaryDataSource;
    public SecondaryConfig(@Qualifier("secondaryDataSource") DataSource secondaryDataSource) {
        this.secondaryDataSource = secondaryDataSource;
    }
    @Bean
    public SqlSessionFactory sqlSessionFactorySecondary() throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(secondaryDataSource);
        return bean.getObject();
    }
    @Bean
    public SqlSessionTemplate sqlSessionTemplateSecondary() throws Exception {
        return new SqlSessionTemplate(sqlSessionFactorySecondary());
    }
}

配置类上使用@MapperScan注解来指定当前数据源下定义的实体和mapper的包路径，还注入了sqlSessionFactory和sqlSessionTemplate，通过@Qualifier注解指定了对应的数据源，其名字对应在DataSourceConfiguration配置类中的数据源定义的函数名。

各个对数据源对应路径下的实体和mapper

@Data
@NoArgsConstructor
public class UserPrimary {
    private Long id;
    private String user_name;
    private Integer age;
    public UserPrimary(String name, Integer age) {
        this.user_name = name;
        this.age = age;
    }
}
public interface UserMapperPrimary {
    @Select("SELECT * FROM USER_0 WHERE USER_NAME = #{name}")
    UserPrimary findByName(@Param("name") String name);
    @Insert("INSERT INTO USER_0 (USER_NAME, AGE) VALUES(#{name}, #{age})")
    int insert(@Param("name") String name, @Param("age") Integer age);
    @Delete("DELETE FROM USER_0")
    int deleteAll();
}

@Data
@NoArgsConstructor
public class UserSecondary {
    private Long id;
    private String user_name;
    private Integer age;
    public UserSecondary(String name, Integer age) {
        this.user_name = name;
        this.age = age;
    }
}
public interface UserMapperSecondary {
    @Select("SELECT * FROM USER_1 WHERE USER_NAME = #{name}")
    UserSecondary findByName(@Param("name") String name);
    @Insert("INSERT INTO USER_1 (USER_NAME, AGE) VALUES(#{name}, #{age})")
    int insert(@Param("name") String name, @Param("age") Integer age);
    @Delete("DELETE FROM USER_1")
    int deleteAll();
}

测试

	@Test
    public void test() {
        // 往Primary数据源插入一条数据
        userMapperPrimary.insert("caocao", 20);
        // 从Primary数据源查询刚才插入的数据，配置正确就可以查询到
        UserPrimary userPrimary = userMapperPrimary.findByName("caocao");
        Assert.assertEquals(20, userPrimary.getAge().intValue());
        // 从Secondary数据源查询刚才插入的数据，配置正确应该是查询不到的
        UserSecondary userSecondary = userMapperSecondary.findByName("caocao");
        Assert.assertNull(userSecondary);
        // 往Secondary数据源插入一条数据
        userMapperSecondary.insert("sunquan", 21);
        // 从Primary数据源查询刚才插入的数据，配置正确应该是查询不到的
        userPrimary = userMapperPrimary.findByName("sunquan");
        Assert.assertNull(userPrimary);
        // 从Secondary数据源查询刚才插入的数据，配置正确就可以查询到
        userSecondary = userMapperSecondary.findByName("sunquan");
        Assert.assertEquals(21, userSecondary.getAge().intValue());
    }