教你使用springboot配置多數(shù)據(jù)源

更新時間：2021年05月23日 10:55:48 作者：Jay_Chou12580

發(fā)現(xiàn)有很多小伙伴還不會用springboot配置多數(shù)據(jù)源,今天特地給大家整理了本篇文章,文中有非常詳細(xì)的圖文介紹及代碼示例,對正在學(xué)習(xí)java的小伙伴很有幫助,需要的朋友可以參考下

一、建庫建表

1.1 創(chuàng)建數(shù)據(jù)庫db1和數(shù)據(jù)庫db2

在這里插入圖片描述

1.2 在數(shù)據(jù)庫db1中創(chuàng)建表db1

在這里插入圖片描述

CREATE TABLE `db1` (
  `id` int unsigned zerofill NOT NULL AUTO_INCREMENT,
  `name` varchar(50) DEFAULT NULL,
  `age` int unsigned zerofill DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8mb4;

1.3 在數(shù)據(jù)庫db2中創(chuàng)建表db2

在這里插入圖片描述

CREATE TABLE `db2` (
  `id` int unsigned zerofill NOT NULL AUTO_INCREMENT,
  `name` varchar(50) DEFAULT NULL,
  `age` int unsigned zerofill DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8mb4;

二、創(chuàng)建springboot項目

2.1 pom.xml導(dǎo)入依賴

<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>2.1.4</version>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <scope>test</scope>
        </dependency>

2.2 創(chuàng)建application.yml文件(與 2.3 二選一進(jìn)行配置,推薦此方法)

server:
  port: 8080 # 啟動端口
spring:
  datasource:
    db1: # 數(shù)據(jù)源1
      jdbc-url: jdbc:mysql://localhost:3306/db1?serverTimezone=Asia/Shanghai&useUnicode=true&characterEncoding=utf8
      username: root
      password: root
      driver-class-name: com.mysql.cj.jdbc.Driver
    db2: # 數(shù)據(jù)源2
      jdbc-url: jdbc:mysql://localhost:3306/db2?serverTimezone=Asia/Shanghai&useUnicode=true&characterEncoding=utf8
      username: root
      password: root
      driver-class-name: com.mysql.cj.jdbc.Driver

2.3 創(chuàng)建application.properties文件(與 2.2 二選一進(jìn)行配置)

server.port=8080

      spring.datasource.db1.url=jdbc:mysql://localhost:3306/db1?serverTimezone=Asia/Shanghai&useUnicode=true&characterEncoding=utf8
      spring.datasource.db1.username=root
      spring.datasource.db1.password=root
      spring.datasource.db1.driver-class-name=com.mysql.jdbc.Driver

      spring.datasource.db2.url=jdbc:mysql://localhost:3306/db2?serverTimezone=Asia/Shanghai&useUnicode=true&characterEncoding=utf8
      spring.datasource.db2.username=root
      spring.datasource.db2.password=root
      spring.datasource.db2.driver-class-name=com.mysql.jdbc.Driver

2.4 創(chuàng)建mapper文件

我個人是放在mapper包下，文件隨便命名的
代碼隨便寫的，測試而已

在這里插入圖片描述

import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Mapper;

/**
 * @Author if
 * @Description: What is it
 * @Date 2021-05-20 下午 09:52
 */
@Mapper
public interface Db1Mapper {
    @Insert("insert into db1(name,age) values('if',18)")
    int add();
}

import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Mapper;

/**
 * @Author if
 * @Description: What is it
 * @Date 2021-05-20 下午 09:52
 */
@Mapper
public interface Db2Mapper {
    @Insert("insert into db2(name,age) values('fi',81)")
    int add();
}

2.5 創(chuàng)建config配置文件

我個人是放在config包下，文件隨便命名的

在這里插入圖片描述

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;

/**
 * @Author if
 * @Description: 注意以下有些文件路徑需要更改
 * @Date 2021-05-20 下午 09:56
 */
@Configuration
@MapperScan(basePackages = "com.ifyyf.study.mapper.db1", sqlSessionFactoryRef = "db1SqlSessionFactory")
public class Db1DataSourceConfig {
    @Bean("db1DataSource")
    @ConfigurationProperties(prefix = "spring.datasource.db1") //讀取application.yml中的配置參數(shù)映射成為一個對象
    public DataSource getDb1DataSource(){
        return DataSourceBuilder.create().build();
    }

    @Bean("db1SqlSessionFactory")
    public SqlSessionFactory db1SqlSessionFactory(@Qualifier("db1DataSource") DataSource dataSource) throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dataSource);
        // mapper的xml形式文件位置必須要配置，不然將報錯：no statement （這種錯誤也可能是mapper的xml中，namespace與項目的路徑不一致導(dǎo)致）
        bean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath*:mapping/db1/*.xml"));
        return bean.getObject();
    }

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

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;

/**
 * @Author if
 * @Description: 注意以下有些文件路徑需要更改
 * @Date 2021-05-20 下午 09:56
 */
@Configuration
@MapperScan(basePackages = "com.ifyyf.study.mapper.db2", sqlSessionFactoryRef = "db2SqlSessionFactory")
public class Db2DataSourceConfig {
    @Bean("db2DataSource")
    @ConfigurationProperties(prefix = "spring.datasource.db2") //讀取application.yml中的配置參數(shù)映射成為一個對象
    public DataSource getDb2DataSource(){
        return DataSourceBuilder.create().build();
    }

    @Bean("db2SqlSessionFactory")
    public SqlSessionFactory db2SqlSessionFactory(@Qualifier("db2DataSource") DataSource dataSource) throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dataSource);
        // mapper的xml形式文件位置必須要配置，不然將報錯：no statement （這種錯誤也可能是mapper的xml中，namespace與項目的路徑不一致導(dǎo)致）
        bean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath*:mapping/db2/*.xml"));
        return bean.getObject();
    }

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

三、測試代碼運(yùn)行

3.1 測試類中測試代碼

springboot項目中測試類進(jìn)行測試

import com.ifyyf.study.mapper.db1.Db1Mapper;
import com.ifyyf.study.mapper.db2.Db2Mapper;
import org.junit.jupiter.api.Test;
import org.springframework.boot.test.context.SpringBootTest;
import javax.annotation.Resource;

@SpringBootTest
class StudyApplicationTests {
    @Resource
    private Db1Mapper db1Mapper;
    @Resource
    private Db2Mapper db2Mapper;
    @Test
    void contextLoads() {
        System.out.println(db1Mapper.add());
        System.out.println(db2Mapper.add());
    }
}