SpringBoot2.0之八多数据源配置

ゝ一世哀愁。 2022-05-26 07:06 156阅读 0赞

在开发的过程中我们可能都会遇到对接公司其他系统等需求，对于外部的系统可以采用接口对接的方式，对于一个公司开发的两个系统，并且知道相关数据库结构的情况下，就可以考虑使用多数据源来解决这个问题。SpringBoot为我们提供了相对简单的实现。

**一、建立如下结构的maven项目**  
![这里写图片描述][70]

**二、添加相关数据库配置信息**

server:
      port: 8080
    
    spring:  
      datasource:
        master:
          driver-class-name: com.mysql.jdbc.Driver
          url: jdbc:mysql://127.0.0.1:3306/test?useUnicode=true&characterEncoding=utf-8&useSSL=false
          username: root
          password: 123456
        slaver:
          driver-class-name: com.mysql.jdbc.Driver
          url: jdbc:mysql://127.0.0.1:3306/dev?useUnicode=true&characterEncoding=utf-8&useSSL=false
          username: root
          password: 123456

**三、主库和从库的相关配置**  
1、主库数据源配置

@Configuration
    @MapperScan(basePackages = "com.somta.springboot.dao.master", sqlSessionTemplateRef  = "masterSqlSessionTemplate")
    public class MasterDataSourceConfiguration {
    
    	@Value("${spring.datasource.master.driver-class-name}")
        private String driverClassName;
    
        @Value("${spring.datasource.master.url}")
        private String url;
    
        @Value("${spring.datasource.master.username}")
        private String username;
    
        @Value("${spring.datasource.master.password}")
        private String password;
    	
        @Bean(name = "masterDataSource")
        @Primary
        public DataSource dataSource() {
        	DruidDataSource dataSource = new DruidDataSource();
            dataSource.setDriverClassName(this.driverClassName);
            dataSource.setUrl(this.url);
            dataSource.setUsername(this.username);
            dataSource.setPassword(this.password);
            return dataSource;
        }
    
        @Bean(name = "masterSqlSessionFactory")
        @Primary
        public SqlSessionFactory sqlSessionFactory(@Qualifier("masterDataSource") DataSource dataSource) throws Exception {
            SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
            bean.setDataSource(dataSource);
            bean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath*:mybatis/master/**/Mysql_*Mapper.xml"));
            return bean.getObject();
        }
    
        @Bean(name = "masterTransactionManager")
        @Primary
        public DataSourceTransactionManager transactionManager(@Qualifier("masterDataSource") DataSource dataSource) {
            return new DataSourceTransactionManager(dataSource);
        }
    
        @Bean(name = "masterSqlSessionTemplate")
        @Primary
        public SqlSessionTemplate sqlSessionTemplate(@Qualifier("masterSqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
            return new SqlSessionTemplate(sqlSessionFactory);
        }
    
    }

2、从库的数据源配置信息

@Configuration
    @MapperScan(basePackages = "com.somta.springboot.dao.slaver", sqlSessionTemplateRef  = "slaverSqlSessionTemplate")
    public class SlaverDataSourceConfiguration {
    
    	@Value("${spring.datasource.slaver.driver-class-name}")
        private String driverClassName;
    
        @Value("${spring.datasource.slaver.url}")
        private String url;
    
        @Value("${spring.datasource.slaver.username}")
        private String username;
    
        @Value("${spring.datasource.slaver.password}")
        private String password;
    	
    	
        @Bean(name = "slaverDataSource")
        public DataSource dataSource() {
        	DruidDataSource dataSource = new DruidDataSource();
            dataSource.setDriverClassName(this.driverClassName);
            dataSource.setUrl(this.url);
            dataSource.setUsername(this.username);
            dataSource.setPassword(this.password);
            return dataSource;
        }
    
        @Bean(name = "slaverSqlSessionFactory")
        public SqlSessionFactory sqlSessionFactory(@Qualifier("slaverDataSource") DataSource dataSource) throws Exception {
            SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
            bean.setDataSource(dataSource);
            bean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath*:mybatis/slaver/**/Mysql_*Mapper.xml"));
            return bean.getObject();
        }
    
        @Bean(name = "slaverTransactionManager")
        public DataSourceTransactionManager transactionManager(@Qualifier("slaverDataSource") DataSource dataSource) {
            return new DataSourceTransactionManager(dataSource);
        }
    
        @Bean(name = "slaverSqlSessionTemplate")
        public SqlSessionTemplate sqlSessionTemplate(@Qualifier("slaverSqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
            return new SqlSessionTemplate(sqlSessionFactory);
        }
    
    }

注意在配置数据源的信息时，一定要通过@Primary配置一个主库，对于数据库配置部分与普通的数据源配置没有差异，新建一个DataSource，在创建一个SqlSessionTemplate，最后创建一个SqlSessionTemplate，分别以此注入即可，@MapperScan注解的扫描路径要分别对于相应的dao层

**四、编写dao层和xml**

public interface UserMasterDao {
    	int addUser(User user);
    	int deleteUserById(Long id);
    	int updateUserById(User user);
    	User queryUserById(Long id);
    	List<User> queryUserList();
    }

<?xml version="1.0" encoding="UTF-8"?>
    <!DOCTYPE mapper
      PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
      "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
    <mapper namespace="com.somta.springboot.dao.master.UserMasterDao" > 
    
    <resultMap id="BaseResultMap" type="com.somta.springboot.pojo.User" >
    	<result column="id" property="id"/>
    	<result column="name" property="name"/>
    	<result column="age" property="age"/>
    </resultMap>
           
    
    <sql id="Base_Column_List" >
    	id, name, age
    </sql>
       
    <insert id="addUser" parameterType="com.somta.springboot.pojo.User" >
    	insert into t_user (id, name, age) 
    	values (#{id},#{name},#{age});
    </insert>
    
    <delete id="deleteUserById" parameterType="java.lang.Long">
     delete from t_user where id=#{id}
    </delete>
    
    <update id="updateUserById" parameterType="com.somta.springboot.pojo.User" >
    	update t_user set 
    	<trim  suffixOverrides="," >
    	<if test="id != null and id != ''">
    		id=#{id},
    	</if>
    	<if test="name != null and name != ''">
    		name=#{name},
    	</if>
    	<if test="age != null and age != ''">
    		age=#{age},
    	</if>
    	</trim> where id=#{id}
    </update>
    
    <select id="queryUserById" resultMap="BaseResultMap" parameterType="java.lang.Long">
    	select <include refid="Base_Column_List" /> 
    	from t_user where id = #{id}
    </select>
    
    <select id="queryUserList" resultMap="BaseResultMap">
    	select <include refid="Base_Column_List" /> 
    	from t_user
    </select>
    
    </mapper>

五、编写测试类进行测试

@RunWith(SpringJUnit4ClassRunner.class)
    @SpringBootTest(classes = Application.class)
    public class MultiDatasourceTest {
    	@Autowired
    	private UserMasterDao masterUserDao;
    	@Autowired
    	private UserSlaverDao slaverUserDao;
    	/**
    	 * 查询用户
    	 * @throws Exception
    	 */
    	@Test
    	public void testQueryUser() throws Exception {
    		User masterUser = masterUserDao.queryUserById(1L);
    		System.out.println("masterUser==>"+masterUser.getName());
    		
    		User slaverUser = slaverUserDao.queryUserById(1L);
    		System.out.println("slaverUser==>"+slaverUser.getName());
    	}
    }

当在控制台看到如下所示输出就代表我们的配置已经成功了  
![这里写图片描述][70 1]

Git代码地址：[https://gitee.com/Somta/SpringBoot/tree/master/SpringBoot-multiDatasource][https_gitee.com_Somta_SpringBoot_tree_master_SpringBoot-multiDatasource]  
原文地址：http://somta.com.cn/\#/blog/view/05ef234aa6744aa4bc039869e2cfaffe

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![二维码][70 2]

[70]: /images/20220526/e248051f57f142a8b0d61665cca02634.png
[70 1]: /images/20220526/cfe63a6745824839903f8653098a3c0d.png
[https_gitee.com_Somta_SpringBoot_tree_master_SpringBoot-multiDatasource]: https://gitee.com/Somta/SpringBoot/tree/master/SpringBoot-multiDatasource
[70 2]: /images/20220526/ed9ae7a85d9b43d1a65505fb2696dc39.png