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Mybatis 多数据源读写分离(注解实现)
首先需要建立两个库进行测试,我这里使用的是 master_test 和 slave_test 两个库,两张库都有一张同样的表(偷懒,喜喜),表结构
表名 t_user
| 字段名 | 类型 | 备注 |
| :——: | :——: | :——: |
| id | int | 主键自增 ID |
| name | varchar | 名称 |
表中分别添加两条不同数据,方便测试
主数据库记录 name 为 xiaobin,从库为 xiaoliu
开始使用 Springboot 整合 mybatis,首先引入 pom 文件
<?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 http://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>2.1.4.RELEASE</version>
</parent>
<groupId>com.xiaobin</groupId>
<artifactId>mysql_master_slave</artifactId>
<version>1.0-SNAPSHOT</version>
<properties>
<java.version>1.8</java.version>
<lombok.version>1.18.6</lombok.version>
<mybatis.version>1.3.2</mybatis.version>
<lombox.version>1.18.6</lombox.version>
</properties>
<dependencies>
<!-- 添加 web 启动坐标 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- 添加 lombok 工具坐标 -->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>${lombok.version}</version>
</dependency>
<!-- 添加 springboot 测试坐标 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
</dependency>
<!-- 添加 lombox 测试坐标 -->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>${lombox.version}</version>
</dependency>
<!-- 添加 mybatis 依赖坐标 -->
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>${mybatis.version}</version>
</dependency>
<!-- 添加 mysql 驱动器坐标 -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>
<!-- 添加 druid 数据源坐标 -->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid-spring-boot-starter</artifactId>
<version>1.1.10</version>
</dependency>
<!-- 添加 AOP 坐标 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-aop</artifactId>
</dependency>
</dependencies>
</project>
动态数据源配置
这里使用的数据源为 druid,实现数据源之间的切换用 @DataSource 自定义注解,配置 Aop 进行切换
application.yml 配置文件
spring:
datasource:
type: com.alibaba.druid.pool.DruidDataSource
druid:
xiaobin-master: # 主数据源
driverClassName: com.mysql.jdbc.Driver
username: root
password: root
url: jdbc:mysql://localhost:3306/master_test?serverTimezone=GMT%2B8&useUnicode=true&characterEncoding=utf8
xiaobin-slave: # 从数据源
driverClassName: com.mysql.jdbc.Driver
username: root
password: root
url: jdbc:mysql://localhost:3306/slave_test?serverTimezone=GMT%2B8&useUnicode=true&characterEncoding=utf8
mybatis:
mapper-locations: classpath:mapper/*.xml
多数据源配置类
package com.xiaobin.config;
import com.alibaba.druid.spring.boot.autoconfigure.DruidDataSourceBuilder;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.stereotype.Component;
import javax.sql.DataSource;
import java.util.HashMap;
import java.util.Map;
/**
* 创建时间:2019/9/22 11:42
* 备注:多数据源配置信息
* 码农自学交流小群:260532022,欢迎大家的加入,分享学习是一件开心事
**/
@Configuration
@Component
public class DynamicDataSourceConfig {
@Bean
@ConfigurationProperties("spring.datasource.druid.xiaobin-master")
public DataSource xiaobinMasterDataSource(){return DruidDataSourceBuilder.create().build();}
@Bean
@ConfigurationProperties("spring.datasource.druid.xiaobin-slave")
public DataSource xiaobinSlaveDataSource(){return DruidDataSourceBuilder.create().build();}
@Bean
@Primary
public DynamicDataSource dataSource(DataSource xiaobinMasterDataSource, DataSource xiaobinSlaveDataSource) {Map<Object, Object> targetDataSources = new HashMap<>();
targetDataSources.put("xiaobin-master",xiaobinMasterDataSource);
targetDataSources.put("xiaobin-slave", xiaobinSlaveDataSource);
return new DynamicDataSource(xiaobinMasterDataSource, targetDataSources);
}
}
动态数据源切换类
package com.xiaobin.config;
import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;
import org.springframework.lang.Nullable;
import javax.sql.DataSource;
import java.util.Map;
/**
* 创建时间:2019/9/22 11:51
* 备注:动态数据源
* 码农自学交流小群:260532022,欢迎大家的加入,分享学习是一件开心事
**/
public class DynamicDataSource extends AbstractRoutingDataSource {private static final ThreadLocal<String> contextHolder = new ThreadLocal<>();
public DynamicDataSource(DataSource defaultTargetDataSource, Map<Object, Object> targetDataSources) {super.setDefaultTargetDataSource(defaultTargetDataSource);
super.setTargetDataSources(targetDataSources);
super.afterPropertiesSet();}
@Override
protected Object determineCurrentLookupKey() {return getDataSource();
}
public static void setDataSource(String dataSource) {contextHolder.set(dataSource);
}
public static String getDataSource() {return contextHolder.get();
}
public static void clearDataSource() {contextHolder.remove();
}
}
自定义 @DataSource 注解
在需要切换数据的 Dao 添加此注解
package com.xiaobin.annotation;
import java.lang.annotation.*;
/**
* 创建时间:2019/9/22 11:53
* 备注:自定义数据源选择注解
* 码农自学交流小群:260532022,欢迎大家的加入,分享学习是一件开心事
**/
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface DataSource {String name() default "";
}
Aop 切面类配置
package com.xiaobin.aspect;
import com.xiaobin.annotation.DataSource;
import com.xiaobin.config.DynamicDataSource;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.stereotype.Component;
import java.lang.reflect.Method;
/**
* 创建时间:2019/9/22 11:54
* 备注:* 码农自学交流小群:260532022,欢迎大家的加入,分享学习是一件开心事
**/
@Aspect
@Component
public class DataSourceAspect {@Pointcut("@annotation(com.xiaobin.annotation.DataSource)")
public void dataSourcePointCut() {}
@Around("dataSourcePointCut()")
public Object around(ProceedingJoinPoint point) throws Throwable {MethodSignature signature = (MethodSignature) point.getSignature();
Method method = signature.getMethod();
DataSource dataSource = method.getAnnotation(DataSource.class);
if(dataSource == null){DynamicDataSource.setDataSource("xiaobin-master");
}else {DynamicDataSource.setDataSource(dataSource.name());
}
try {return point.proceed();
} finally {DynamicDataSource.clearDataSource();
}
}
}
启动配置注解信息,重要(不然运行会报错)
package com.xiaobin;
import com.xiaobin.config.DynamicDataSourceConfig;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
import org.springframework.context.annotation.Import;
/**
* 创建时间:2019/9/22 11:17
* 备注:* 码农自学交流小群:260532022,欢迎大家的加入,分享学习是一件开心事
**/
@SpringBootApplication(exclude= {DataSourceAutoConfiguration.class})
@MapperScan(basePackages = "com.xiaobin.mapper")
@Import({DynamicDataSourceConfig.class})
public class StartApp {public static void main(String[] args) {SpringApplication.run(StartApp.class);
}
}
测试 controller
package com.xiaobin.api;
import com.xiaobin.Entity.TUser;
import com.xiaobin.mapper.UserMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import java.util.List;
/**
* 创建时间:2019/9/22 12:08
* 备注:* 码农自学交流小群:260532022,欢迎大家的加入,分享学习是一件开心事
**/
@RestController
@RequestMapping
public class UserController {
@Autowired
private UserMapper userMapper;
@GetMapping("/{name}/list")
public List<TUser> list(@PathVariable("name")String name){if(name.equals("master")){return userMapper.queryAllWithMaster();
}else{return userMapper.queryAllWithSlave();
}
}
}
效果图
更具路径传值,进行主从数据源切换
目录结构
源码地址(数据库需要自己创建)https://gitee.com/MyXiaoXiaoB…
码农自学交流小群:260532022,欢迎大家的加入,分享学习是一件开心事
正文完
发表至: java
2019-09-22