springboot整合多数据源配置方式
时间:2023-01-17 12:46:56|栏目:JAVA代码|点击: 次
简介
主要介绍两种整合方式,分别是 springboot+mybatis 使用分包方式整合,和 springboot+druid+mybatisplus 使用注解方式整合。
一、表结构
在本地新建两个数据库,名称分别为db1
和db2
,新建一张user
表,表结构如下:
SQL代码:
CREATE TABLE `user` ( `id` int(11) NOT NULL AUTO_INCREMENT COMMENT '主键', `name` varchar(25) NOT NULL COMMENT '姓名', `age` int(2) DEFAULT NULL COMMENT '年龄', `sex` tinyint(1) NOT NULL DEFAULT '0' COMMENT '性别:0-男,1-女', `addr` varchar(100) DEFAULT NULL COMMENT '地址', PRIMARY KEY (`id`) ) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8
二、多数据源整合
1. springboot+mybatis使用分包方式整合
1.1 主要依赖包
- spring-boot-starter-web
- mybatis-spring-boot-starter
- mysql-connector-java
- lombok
pom.xml
文件如下:
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.1.9.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.example</groupId> <artifactId>multipledatasource</artifactId> <version>0.0.1-SNAPSHOT</version> <name>multipledatasource</name> <description>Demo project for Spring Boot</description> <properties> <java.version>1.8</java.version> </properties> <dependencies> <!-- spring 依赖 --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <!-- mysql 依赖 --> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>2.1.0</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <optional>true</optional> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project>
1.2 application.yml 配置文件
server: port: 8080 # 启动端口 spring: datasource: db1: # 数据源1 jdbc-url: jdbc:mysql://localhost:3306/db1?characterEncoding=utf8&useUnicode=true&useSSL=false&serverTimezone=GMT%2B8 username: root password: root driver-class-name: com.mysql.cj.jdbc.Driver db2: # 数据源2 jdbc-url: jdbc:mysql://localhost:3306/db2?characterEncoding=utf8&useUnicode=true&useSSL=false&serverTimezone=GMT%2B8 username: root password: root driver-class-name: com.mysql.cj.jdbc.Driver
注意事项
各个版本的 springboot 配置 datasource 时参数有所变化,例如低版本配置数据库 url 时使用 url 属性,高版本使用 jdbc-url 属性,请注意区分。
1.3 建立连接数据源的配置文件
第一个配置文件
@Configuration @MapperScan(basePackages = "com.example.multipledatasource.mapper.db1", 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/db1/*.xml")); return bean.getObject(); } @Primary @Bean("db1SqlSessionTemplate") public SqlSessionTemplate db1SqlSessionTemplate(@Qualifier("db1SqlSessionFactory") SqlSessionFactory sqlSessionFactory){ return new SqlSessionTemplate(sqlSessionFactory); } }
第二个配置文件
@Configuration @MapperScan(basePackages = "com.example.multipledatasource.mapper.db2", 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/db2/*.xml")); return bean.getObject(); } @Bean("db2SqlSessionTemplate") public SqlSessionTemplate db1SqlSessionTemplate(@Qualifier("db2SqlSessionFactory") SqlSessionFactory sqlSessionFactory){ return new SqlSessionTemplate(sqlSessionFactory); } }
1.4 具体实现
项目结构如下:
注意事项
- 在 service 层中根据不同的业务注入不同的 dao 层
- 如果是主从复制- -读写分离:比如 db1 中负责增删改,db2 中负责查询。但是需要注意的是负责增删改的数据库必须是主库(master)
2. springboot+druid+mybatisplus使用注解整合
2.1 主要依赖包
- spring-boot-starter-web
- mybatis-plus-boot-starter
- dynamic-datasource-spring-boot-starter # 配置动态数据源
- druid-spring-boot-starter # 阿里的数据库连接池
- mysql-connector-java
- lombok
pom.xml
文件如下:
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.1.9.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.example</groupId> <artifactId>mutipledatasource2</artifactId> <version>0.0.1-SNAPSHOT</version> <name>mutipledatasource2</name> <description>Demo project for Spring Boot</description> <properties> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus-boot-starter</artifactId> <version>3.2.0</version> </dependency> <dependency> <groupId>com.baomidou</groupId> <artifactId>dynamic-datasource-spring-boot-starter</artifactId> <version>2.5.6</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid-spring-boot-starter</artifactId> <version>1.1.20</version> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <optional>true</optional> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> <profiles> <profile> <id>local1</id> <properties> <profileActive>local1</profileActive> </properties> <activation> <activeByDefault>true</activeByDefault> </activation> </profile> <profile> <id>local2</id> <properties> <profileActive>local2</profileActive> </properties> </profile> </profiles> </project>
2.2 application.yml 配置文件
server: port: 8080 spring: datasource: dynamic: primary: db1 # 配置默认数据库 datasource: db1: # 数据源1配置 url: jdbc:mysql://localhost:3306/db1?characterEncoding=utf8&useUnicode=true&useSSL=false&serverTimezone=GMT%2B8 username: root password: root driver-class-name: com.mysql.cj.jdbc.Driver db2: # 数据源2配置 url: jdbc:mysql://localhost:3306/db2?characterEncoding=utf8&useUnicode=true&useSSL=false&serverTimezone=GMT%2B8 username: root password: root driver-class-name: com.mysql.cj.jdbc.Driver durid: initial-size: 1 max-active: 20 min-idle: 1 max-wait: 60000 autoconfigure: exclude: com.alibaba.druid.spring.boot.autoconfigure.DruidDataSourceAutoConfigure # 去除druid配置
DruidDataSourceAutoConfigure
会注入一个DataSourceWrapper
,其会在原生的spring.datasource
下找 url, username, password 等。动态数据源 URL 等配置是在 dynamic 下,因此需要排除,否则会报错。排除方式有两种,一种是上述配置文件排除,还有一种可以在项目启动类排除:
@SpringBootApplication(exclude = DruidDataSourceAutoConfigure.class) public class Application { public static void main(String[] args) { SpringApplication.run(Application.class, args); } }
2.3 给使用非默认数据源添加注解@DS
@DS
可以注解在方法上和类上,同时存在方法注解优先于类上注解。
注解在 service 实现或 mapper 接口方法上,不要同时在 service 和 mapper 注解。
@DS("db2") public interface UserMapper extends BaseMapper<User> { } @Service @DS("db2") public class ModelServiceImpl extends ServiceImpl<ModelMapper, Model> implements IModelService {} @Select("SELECT * FROM user") @DS("db2") List<User> selectAll();