創建SpringBoot項目就不說了。(直接使用IDEA創建就好了)
整個目錄結構如圖:(不用管圖中報錯,項目是在另一臺電腦上寫的。報錯是沒有jar包,因為網絡比較慢。)
1、主要pom.xml
<dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><!-- Spring Boot Test 依賴 --><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency><!-- Spring Boot Mybatis 依賴 --><dependency><groupId>org.mybatis.spring.boot</groupId><artifactId>mybatis-spring-boot-starter</artifactId><version>1.2.0</version></dependency> <!-- MySQL 連接驅動依賴 --><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><version>${mysql-connector}</version></dependency> <!-- Druid 數據連接池依賴 --><dependency><groupId>com.alibaba</groupId><artifactId>druid</artifactId><version>1.0.18</version></dependency><dependency><groupId>junit</groupId><artifactId>junit</artifactId><version>3.8.1</version><scope>test</scope></dependency><dependency><groupId>com.microsoft.sqlserver</groupId><artifactId>mssql-jdbc</artifactId><version>7.0.0.jre8</version></dependency></dependencies>
2、在配置文件中配置多數據源application.properties
## 默認的數據源
master.datasource.url=jdbc:mysql://localhost:3306/springbootdb?useUnicode=true&characterEncoding=utf8&allowMultiQueries=true
master.datasource.username=root
master.datasource.password=admin
master.datasource.driverClassName=com.mysql.jdbc.Driver
## 另一個的數據源
cluster.datasource.url=jdbc:sqlserver://localhost:1433;DatabaseName=tablename
cluster.datasource.username=sa
cluster.datasource.password=admin
cluster.datasource.driverClassName=com.microsoft.sqlserver.jdbc.SQLServerDriver
?我這配置SqlServer、MySql,如果需要連接MySql中的兩個數據庫。請自行更更改配置,并刪除pom依賴。
3、配置mapper接口的數據源
MasterDataSourceConfig.java
package com.wzq.datasource2.config;import javax.sql.DataSource;import com.alibaba.druid.pool.DruidDataSource;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.beans.factory.annotation.Value;
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 org.springframework.jdbc.datasource.DataSourceTransactionManager;@Configuration
//掃描 Mapper 接口并容器管理
@MapperScan(basePackages = {"com.wzq.datasource2.mapper.master"}, sqlSessionFactoryRef = "masterSqlSessionFactory")
public class MasterDataSourceConfig {// 精確到 master 目錄,以便跟其他數據源隔離static final String PACKAGE = "com.wzq.datasource2.mapper.master";static final String MAPPER_LOCATION = "classpath:mapper/master/*.xml";@Value("${master.datasource.url}")private String url;@Value("${master.datasource.username}")private String user;@Value("${master.datasource.password}")private String password;@Value("${master.datasource.driverClassName}")private String driverClass;@Primary@Bean(name = "masterDataSource")public DataSource masterDataSource() {DruidDataSource dataSource = new DruidDataSource();dataSource.setDriverClassName(driverClass);dataSource.setUrl(url);dataSource.setUsername(user);dataSource.setPassword(password);return dataSource;}@Bean(name = "masterTransactionManager")@Primarypublic DataSourceTransactionManager masterTransactionManager() {return new DataSourceTransactionManager(masterDataSource());}@Bean(name = "masterSqlSessionFactory")@Primarypublic SqlSessionFactory masterSqlSessionFactory(@Qualifier("masterDataSource") DataSource masterDataSource)throws Exception {final SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean();sessionFactory.setDataSource(masterDataSource);sessionFactory.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath:mapper/master/*.xml"));return sessionFactory.getObject();}
}
4、創建entity實體類
public class StuT {private static final long serialVersionUID = 1L;private Integer id;private String name;//get/set}public class Stu {private static final long serialVersionUID = 1L;private Integer id;private String name;//get/set
}
ClusterDataSourceConfig.java
package com.wzq.datasource2.config;import javax.sql.DataSource;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;import com.alibaba.druid.pool.DruidDataSource;@Configuration
//掃描 Mapper 接口并容器管理
@MapperScan(basePackages = {"com.wzq.datasource2.mapper.cluster"}, sqlSessionFactoryRef = "clusterSqlSessionFactory")
public class ClusterDataSourceConfig {// 精確到 cluster 目錄,以便跟其他數據源隔離static final String PACKAGE = "com.wzq.datasource2.mapper.cluster";static final String MAPPER_LOCATION = "classpath:mapper/cluster/*.xml";@Value("${cluster.datasource.url}")private String url;@Value("${cluster.datasource.username}")private String user;@Value("${cluster.datasource.password}")private String password;@Value("${cluster.datasource.driverClassName}")private String driverClass;@Bean(name = "clusterDataSource")public DataSource clusterDataSource() {DruidDataSource dataSource = new DruidDataSource();dataSource.setDriverClassName(driverClass);dataSource.setUrl(url);dataSource.setUsername(user);dataSource.setPassword(password);return dataSource;}@Bean(name = "clusterTransactionManager")public DataSourceTransactionManager clusterTransactionManager() {return new DataSourceTransactionManager(clusterDataSource());}@Bean(name = "clusterSqlSessionFactory")public SqlSessionFactory clusterSqlSessionFactory(@Qualifier("clusterDataSource") DataSource clusterDataSource)throws Exception {final SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean();sessionFactory.setDataSource(clusterDataSource);sessionFactory.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath:mapper/cluster/*.xml"));return sessionFactory.getObject();}
}
請根據實體類自行創建表?
5、編寫mapper層
?
?
6、Service省略,目錄結構如下:
?7、controller層
package com.wzq.datasource2.controller;import com.wzq.datasource2.entity.cluster.StuT;
import com.wzq.datasource2.entity.master.Stu;
import com.wzq.datasource2.service.cluster.StuTService;
import com.wzq.datasource2.service.master.StuService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;import java.util.List;@Controller
public class StuController {@Autowired@Qualifier(value = "stuServiceImpl")private StuService stuService;@Autowired@Qualifier(value = "stuTServiceImpl")private StuTService stuTService;@RequestMapping("/list")@ResponseBodypublic List<Stu> getAllStu(){return stuService.getAllStu();}@RequestMapping("/list2")@ResponseBodypublic List<StuT> getAllStuT(){return stuTService.getAllStuT();}}
總結:
1、配置多數據的目的是因為新項目需要用到老項目中的數據,而數據存放在兩個不同的數據庫當中,配置多數據源能很好的解決這一方面。還有一些公司進行了分庫的操作,就比如一個指定增刪改,一個指定查詢。
2、?可能是我在配置數據源的時候使用了master或cluster,亦或者在配置mapper接口的數據源時指定的mastter或cluster,所以需要在mapperwen文件下創建master和cluster文件,以此來區分數據源的使用。
PS:報紅是因為沒有jar包!報紅是因為沒有jar包!報紅是因為沒有jar包!
GitHub網址:https://github.com/qz596766829/WzqRepository.git?(datasoutrce2項目)
其他實現方式可以參考?SpringBoot + mybatis-plus 實現多數據源SpringBoot + mybatis-plus 實現多數據源。https://blog.csdn.net/qq_38080370/article/details/127514072?實現,通過注解的方式來指定數據源,而不用通過目錄的方式來控制。