springboot系列10： 多数据源

多数据源配置实战（整合MyBatis）

• 首先要在@SpringBootApplication排除该类，因为它会读取application.properties文件的spring.datasource.*属性并自动配置单数据源

package com.example.multi.datasource;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;

@SpringBootApplication(exclude = {
        DataSourceAutoConfiguration.class
})
public class SpringbootStartApplication {

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

 

• 在application.properties中配置多数据源连接信息，需要几个就配置几个，名字可以自由命名代替db1,db2

# database
db.conn.str = useUnicode=true&characterEncoding=UTF-8&zeroDateTimeBehavior=convertToNull&useLocalSessionState=true&tinyInt1isBit=false&serverTimezone=GMT%2B8

spring.datasource.db1.jdbc-url=jdbc:mysql://localhost:3306/multi_test1?${db.conn.str}
spring.datasource.db1.username=root
spring.datasource.db1.password=111111
spring.datasource.db1.driver-class-name=com.mysql.jdbc.Driver

spring.datasource.db2.jdbc-url=jdbc:mysql://localhost:3306/multi_test2?${db.conn.str}
spring.datasource.db2.username=root
spring.datasource.db2.password=111111
spring.datasource.db2.driver-class-name=com.mysql.jdbc.Driver

 

注意：这里请一定将spring.datasource.db1.url改为spring.datasource.db1.jdbc-url

• 手动创建数据库配置类

package com.example.multi.datasource.config;

import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import javax.sql.DataSource;

@Configuration
public class DataSourceConfig {

    @Bean(name = "db1")
    @ConfigurationProperties(prefix = "spring.datasource.db1")
    public DataSource businessDbDataSource() {
        return DataSourceBuilder.create().build();
    }

    @Bean(name = "db2")
    @ConfigurationProperties(prefix = "spring.datasource.db2")
    public DataSource newhomeDbDataSource() {
        return DataSourceBuilder.create().build();
    }
}

 

• 分别配置不同数据源的mybatis的SqlSessionFactory

创建Db1Config:

 

package com.example.multi.datasource.config;

import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.SqlSessionTemplate;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;

import javax.sql.DataSource;

@Configuration
@MapperScan(basePackages = {"com.example.multi.datasource.mapper.db1"}, sqlSessionFactoryRef = "sqlSessionFactoryDb1")
public class Db1Config {

    @Autowired
    @Qualifier("db1")
    private DataSource dataSourceDb1;


    @Bean
    public SqlSessionFactory sqlSessionFactoryDb1() throws Exception {
        SqlSessionFactoryBean factoryBean = new SqlSessionFactoryBean();
        factoryBean.setDataSource(dataSourceDb1);
        factoryBean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath*:mapper/db1/*.xml"));
        return factoryBean.getObject();
    }

    @Bean
    public SqlSessionTemplate sqlSessionTemplateDb1() throws Exception {
        return new SqlSessionTemplate(sqlSessionFactoryDb1());
    }
}

 创建Db2Config:

 

package com.example.multi.datasource.config;

import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.SqlSessionTemplate;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;

import javax.sql.DataSource;

@Configuration
@MapperScan(basePackages = {"com.example.multi.datasource.mapper.db2"}, sqlSessionFactoryRef = "sqlSessionFactoryDb2")
public class Db2Config {

    @Autowired
    @Qualifier("db2")
    private DataSource dataSourceDb2;


    @Bean
    public SqlSessionFactory sqlSessionFactoryDb2() throws Exception {
        SqlSessionFactoryBean factoryBean = new SqlSessionFactoryBean();
        factoryBean.setDataSource(dataSourceDb2);
        factoryBean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath*:mapper/db2/*.xml"));
        return factoryBean.getObject();
    }

    @Bean
    public SqlSessionTemplate sqlSessionTemplateDb2() throws Exception {
        return new SqlSessionTemplate(sqlSessionFactoryDb2());
    }
}

 

注意：此步一定要添加mapper.xml文件扫描路径，否则报错Invalid bound statement (not found)

 

• 完成这些配置后，假设我们有2个Mapper mapper.db1.xxxMapper和mapper.db2.xxxMapper，我们在程序的任何位置使用前者时会自动连接db1库，后者连接db2库。