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();
原文地址:https://www.cnblogs.com/aizen-sousuke/p/11756279.html
时间: 2024-10-28 20:48:24