一、背景

使用spring boot配置多数据源，数据源分别为postgresql、mysql

二、版本介绍

• spring boot——2.5.4
• druid——1.2.11
• postgresql——12
• mysql——8.0.16
• maven——3.0
• idea——2019

三、项目结构

java package目录

resource目录存放mapper.xml文件，按照数据源创建package 

 

四、maven依赖 

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.alibaba/fastjson -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>2.0.4</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.alibaba/druid-spring-boot-starter -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.2.11</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.3.2</version>
        </dependency>
        <dependency>
            <groupId>org.postgresql</groupId>
            <artifactId>postgresql</artifactId>
            <scope>runtime</scope>
        </dependency>
        <!-- MySql驱动 -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>

五、yaml配置文件

server:
  port: 8081
spring:
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource
    druid:
      web-stat-filter:
        enabled: true #是否启用StatFilter默认值true
        url-pattern: /*
        exclusions: /druid/*,*.js,*.gif,*.jpg,*.bmp,*.png,*.css,*.ico
        session-stat-enable: true
        session-stat-max-count: 10
      stat-view-servlet:
        enabled: true #是否启用StatViewServlet默认值true
        url-pattern: /druid/*
        reset-enable: true
        login-username: admin
        login-password: admin
        allow:

      db1:
        username: postgres
        password: localhost
        url: jdbc:postgresql://localhost:5432/test
        driver-class-name: org.postgresql.Driver
        initial-size: 5  # 初始化大小
        min-idle: 5  # 最小
        max-active: 100  # 最大
        max-wait: 60000  # 配置获取连接等待超时的时间
        validation-query: select version()
        time-between-eviction-runs-millis: 60000  # 配置间隔多久才进行一次检测，检测需要关闭的空闲连接，单位是毫秒
        min-evictable-idle-time-millis: 300000  # 指定一个空闲连接最少空闲多久后可被清除，单位是毫秒
        filters: config,wall,stat  # 配置监控统计拦截的filters，去掉后监控界面sql无法统计，'wall'用于防火墙
        # 通过connectProperties属性来打开mergeSql功能；慢SQL记录
        connectionProperties: druid.stat.slowSqlMillis=200;druid.stat.logSlowSql=true;config.decrypt=false
        test-while-idle: true
        test-on-borrow: true
        test-on-return: false
        # 是否缓存preparedStatement，也就是PSCache  官方建议MySQL下建议关闭   个人建议如果想用SQL防火墙 建议打开
        pool-prepared-statements: true
        max-pool-prepared-statement-per-connection-size: 20

      db2:
        username: root
        password: localhost
        url: jdbc:mysql://localhost:3306/springboot?characterEncoding=utf8&useUnicode=true&useSSL=false&serverTimezone=Asia/Shanghai
        driver-class-name: com.mysql.cj.jdbc.Driver
        initial-size: 5  # 初始化大小
        min-idle: 5  # 最小
        max-active: 100  # 最大
        max-wait: 60000  # 配置获取连接等待超时的时间
        validation-query: select 'x'
        time-between-eviction-runs-millis: 60000  # 配置间隔多久才进行一次检测，检测需要关闭的空闲连接，单位是毫秒
        min-evictable-idle-time-millis: 300000  # 指定一个空闲连接最少空闲多久后可被清除，单位是毫秒
        filters: config,wall,stat  # 配置监控统计拦截的filters，去掉后监控界面sql无法统计，'wall'用于防火墙
        # 通过connectProperties属性来打开mergeSql功能；慢SQL记录
        connectionProperties: druid.stat.slowSqlMillis=200;druid.stat.logSlowSql=true;config.decrypt=false
        test-while-idle: true
        test-on-borrow: true
        test-on-return: false
        # 是否缓存preparedStatement，也就是PSCache  官方建议MySQL下建议关闭   个人建议如果想用SQL防火墙 建议打开
        pool-prepared-statements: true
        max-pool-prepared-statement-per-connection-size: 20

mybatis:
  mapper-locations: classpath:com/demo/mapper/*.xml
  type-aliases-package: com.demo.entity
  configuration:
    log-impl:
    mapUnderscoreToCamelCase: true

#showSql
logging:
  level:
    java.sql: debug
    org.apache.ibatis: debug
    com.demo.mapper: debug
  config: classpath:logback-spring.xml

六、数据源配置文件

@Configuration
@MapperScan(basePackages = "com.demo.mapper.postgre.**", sqlSessionFactoryRef = "oneSqlSessionFactory")
public class DataSourceConfig1 {
    // 将这个对象放入Spring容器中
    @Bean(name = "oneDataSource")
    // 表示这个数据源是默认数据源
    @Primary
    // 读取application.properties中的配置参数映射成为一个对象
    // prefix表示参数的前缀
    @ConfigurationProperties(prefix = "spring.datasource.druid.db1")
    public DataSource getDateSource1() {
        return DataSourceBuilder.create().type(DruidDataSource.class).build();
    }

    @Bean(name = "oneSqlSessionFactory")
    // 表示这个数据源是默认数据源
    @Primary
    // @Qualifier表示查找Spring容器中名字为oneDataSource的对象
    public SqlSessionFactory oneSqlSessionFactory(@Qualifier("oneDataSource") DataSource datasource)
            throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(datasource);
        bean.setMapperLocations(
                // 设置mybatis的xml所在位置
                new PathMatchingResourcePatternResolver().getResources("classpath*:com.demo.mapper.postgre/*.xml"));
        return bean.getObject();
    }

    @Bean("oneSqlSessionTemplate")
    // 表示这个数据源是默认数据源
    @Primary
    public SqlSessionTemplate oneSqlSessionTemplate(
            @Qualifier("oneSqlSessionFactory") SqlSessionFactory sessionFactory) {
        return new SqlSessionTemplate(sessionFactory);
    }

}

@Configuration
@MapperScan(basePackages = "com.demo.mapper.mysql", sqlSessionFactoryRef = "twoSqlSessionFactory")
public class DataSourceConfig2 {
    // 将这个对象放入Spring容器中
    @Bean(name = "twoDataSource")
    // 读取application.properties中的配置参数映射成为一个对象
    // prefix表示参数的前缀
    @ConfigurationProperties(prefix = "spring.datasource.druid.db2")
    public DataSource getDateSource1() {
        return DataSourceBuilder.create().type(DruidDataSource.class).build();
    }

    @Bean(name = "twoSqlSessionFactory")
    // 表示这个数据源是默认数据源
    //@Primary
    // @Qualifier表示查找Spring容器中名字为oneDataSource的对象
    public SqlSessionFactory oneSqlSessionFactory(@Qualifier("twoDataSource") DataSource datasource)
            throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(datasource);
        bean.setMapperLocations(
                // 设置mybatis的xml所在位置
                new PathMatchingResourcePatternResolver().getResources("classpath*:com.demo.mapper.mysql/*.xml"));
        return bean.getObject();
    }

    @Bean("twoSqlSessionTemplate")
    // 表示这个数据源是默认数据源
    //@Primary
    public SqlSessionTemplate oneSqlSessionTemplate(
            @Qualifier("twoSqlSessionFactory") SqlSessionFactory sessionFactory) {
        return new SqlSessionTemplate(sessionFactory);
    }

}

七、启动类配置

关键点：去除  exclude = {DataSourceAutoConfiguration.class} 及扫描 com.demo.mapper目录

@MapperScan("com.demo.mapper")
@SpringBootApplication(exclude = {DataSourceAutoConfiguration.class})
public class DemoApplication {

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

八、druid管理页面

输入地址 localhost://8081/druid，输入 admin/admin     

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