多数据源按项目路径配置

1、yml配置

spring:
  datasource:
    db1: #数据库1
      username: root
      password: 123456
      jdbc-url: jdbc:mysql://ip:3306/数据库名?useUnicode=true&characterEncoding=utf-8&useSSL=true&serverTimezone=UTC
      type: com.alibaba.druid.pool.DruidDataSource
      driver-class-name: com.mysql.cj.jdbc.Driver
    db2: #数据库2
      username: root
      password: 123456
      jdbc-url: jdbc:mysql://ip:3306/数据库名?useUnicode=true&characterEncoding=utf-8&useSSL=true&serverTimezone=UTC
      type: com.alibaba.druid.pool.DruidDataSource
      driver-class-name: com.mysql.cj.jdbc.Driver

2、数据源配置

（1）

package com.du.alldemo.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.Qualifier;
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 org.springframework.context.annotation.Primary;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;

import javax.sql.DataSource;

@Configuration
@MapperScan(basePackages = "com.du.alldemo.mapping.mapper1", sqlSessionFactoryRef = "db1SqlSessionFactory")
public class DataSourceConfig1 {

    @Primary // 表示这个数据源是默认数据源, 这个注解必须要加，因为不加的话spring将分不清楚那个为主数据源（默认数据源）
    @Bean("db1DataSource")
    @ConfigurationProperties(prefix = "spring.datasource.db1") //读取application.yml中的配置参数映射成为一个对象
    public DataSource getDb1DataSource(){
        return DataSourceBuilder.create().build();
    }

    @Primary
    @Bean("db1SqlSessionFactory")
    public SqlSessionFactory db1SqlSessionFactory(@Qualifier("db1DataSource") DataSource dataSource) throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dataSource);
        // mapper的xml形式文件位置必须要配置，不然将报错：no statement （这种错误也可能是mapper的xml中，namespace与项目的路径不一致导致）
        bean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath*:mapping/mapper1/*.xml"));
        return bean.getObject();
    }

    @Primary
    @Bean("db1SqlSessionTemplate")
    public SqlSessionTemplate db1SqlSessionTemplate(@Qualifier("db1SqlSessionFactory") SqlSessionFactory sqlSessionFactory){
        return new SqlSessionTemplate(sqlSessionFactory);
    }
}

（2）

package com.du.alldemo.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.Qualifier;
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 org.springframework.core.io.support.PathMatchingResourcePatternResolver;

import javax.sql.DataSource;

@Configuration
@MapperScan(basePackages = "com.du.alldemo.mapping.mapper2", sqlSessionFactoryRef = "db2SqlSessionFactory")
public class DataSourceConfig2 {

    @Bean("db2DataSource")
    @ConfigurationProperties(prefix = "spring.datasource.db2")
    public DataSource getDb1DataSource(){
        return DataSourceBuilder.create().build();
    }

    @Bean("db2SqlSessionFactory")
    public SqlSessionFactory db1SqlSessionFactory(@Qualifier("db2DataSource") DataSource dataSource) throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dataSource);
        bean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath*:mapping/mapper2/*.xml"));
        return bean.getObject();
    }

    @Bean("db2SqlSessionTemplate")
    public SqlSessionTemplate db1SqlSessionTemplate(@Qualifier("db2SqlSessionFactory") SqlSessionFactory sqlSessionFactory){
        return new SqlSessionTemplate(sqlSessionFactory);
    }
}

后续业务需求可以按照对应数据源配置中mapper路径来编写对应mapper及mapper.xml