切面动态数据源&数据库连接池org.mybatis

 

1，对接口interface使用切面需要2.0以上版本
<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.7.RELEASE</version>
    </parent>,
2，需要在某一个数据源上加@Primary ,否则默认装配数据源会报找到多个数据源错误

SpringBoot 实现动态切换数据源 https://mp.weixin.qq.com/s/R8vTrINMOwxhr2lfzyDrtQ　　

 扫描类引入的是 tk.mybatis.spring.annotation.MapperScan

自定义MyBaseMapper不能放在scan扫描包内
import tk.mybatis.mapper.common.Mapper;
public interface MyBaseMapper<T> extends Mapper<T> {
}

本质就是切换数据源

org.mybatis

DateSource 定义注解
DateSourceContext 定义ThreadLocal上下文
DataSourceRouteAspect会拦截注解dataSource的方法，业务方法之前设置数据源，设置到ThreadLocal中
                     也可根据业务参数自主设置数据源，达到分库效果 
DruidConfig 配置多数据源
MybatisConfig 扫描sql配置类
RouteDataSource 通过继承AbstractRoutingDataSource重写，获取ThreadLocal中的数据源



@Target({ ElementType.METHOD,ElementType.TYPE,ElementType.PARAMETER})
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface DataSource {
    String value() default  "";
}

public class DataSourceContext {
    private static final ThreadLocal<String> context = new ThreadLocal<>();
    public static void setDataSource(String value){
        context.set(value);
    }
    public static String getDataSource(){
        return context.get();
    }
    public static void clearDataSource(){
        context.remove();
    }
}

@Aspect
@Component
public class DataSourceRouteAspect {
    @Before("@annotation(dataSource)")
    public void selectDateSource(JoinPoint point, DataSource dataSource){
        String value = dataSource.value();
        DataSourceContext.setDataSource(value);
    }
    @After("@annotation(dataSource)")
    public void removeDataSource(JoinPoint point, DataSource dataSource){
        DataSourceContext.clearDataSource();
    }
}

@Configuration
public class DruidConfig {
//    @Value("${mysql.one.aliasName}")
//    private String aliasNameOne;
//    @Primary
    @Bean(name="dataSourceOne",initMethod = "init",destroyMethod = "close")
    @ConfigurationProperties(prefix = "mysql.one")
    public DruidDataSource dataSourceOne(){
        DruidDataSource dataSource = new DruidDataSource();
        dataSource.setQueryTimeout(300);
        dataSource.setTestWhileIdle(true);
        dataSource.setTestOnBorrow(true);
        dataSource.setTestOnReturn(true);
        dataSource.setTimeBetweenEvictionRunsMillis(600000);
        dataSource.setMinEvictableIdleTimeMillis(300000);
        return dataSource;
    }
//    @Bean(name="dataSourceTwo",initMethod = "init",destroyMethod = "close")
//    @ConfigurationProperties(prefix = "mysql.two")
//    public DruidDataSource dataSourceOne(){
//        return dataSource;
//    }
    @Bean(name = "routeDataSource")
    public RouteDataSource dataSource(@Qualifier("dataSourceOne")DruidDataSource dataSourceOne
//    ,@Qualifier("dataSourceTwo")DruidDataSource dataSourceTwo
    ){
        Map<Object, Object> targetDataSources = new HashMap<>();
        targetDataSources.put("dataSourceOne",dataSourceOne);
//        targetDataSources.put("dataSourceTwo",dataSourceTwo);
        RouteDataSource dataSource = new RouteDataSource();
        dataSource.setTargetDataSources(targetDataSources);
        dataSource.setDefaultTargetDataSource(dataSourceOne);
        System.out.println("routeDataSource******************"+dataSource);
        return  dataSource;
    }
}




import org.apache.ibatis.mapping.Environment;
import org.apache.ibatis.transaction.TransactionFactory;
import org.apache.ibatis.transaction.jdbc.JdbcTransactionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import tk.mybatis.spring.annotation.MapperScan
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.transaction.PlatformTransactionManager;

@Configuration
@MapperScan("cn.com.xmh.ibatisMapper")
public class MybatisConfig {
    @Autowired
    private RouteDataSource routeDataSource;
    @Bean(name="SqlSessionFactory")
//    @Primary
    public SqlSessionFactoryBean sqlSessionFactoryBean(){
        TransactionFactory transactionFactory = new JdbcTransactionFactory();
        Environment environment = new Environment("mytest",transactionFactory,routeDataSource);
        org.apache.ibatis.session.Configuration configuration = new  org.apache.ibatis.session.Configuration(environment);
        configuration.setMapUnderscoreToCamelCase(true);
        SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
        sqlSessionFactoryBean.setDataSource(routeDataSource);
        sqlSessionFactoryBean.setConfiguration(configuration);
        return  sqlSessionFactoryBean;
    }
    @Bean(name="transactionManager")
    @Primary
    public PlatformTransactionManager transactionManager(){
        return  new DataSourceTransactionManager(routeDataSource);
    }


}




mapper配置类
import cn.com.config.dbConfig.DataSource;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Select;
@Mapper
public interface MyTestIbatis extends BaseMapper<String>{
    @DataSource("dataSourceOne")
    @Select("select id from tbl_user")
    List<String> selectStr();
}

import tk.mybatis.mapper.common.Mapper;
public interface MyBaseMapper<T> extends Mapper<T> {
}


@Autowired
MyTestIbatis myTestIbatis;
myTestIbatis.selectStr()
　　


 <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>2.0.0</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.4.6</version>
        </dependency>

spring.datasource.url=jdbc:mysql://127.0.0.1/xmh
spring.datasource.username=root
spring.datasource.password=admin
spring.datasource.driver-class-name=com.mysql.jdbc.Driver

mysql.one.url=jdbc:mysql://127.0.0.1/xmh
mysql.one.userName=root
mysql.one.password=admin
mysql.one.initialSize= 5
mysql.one.minIdle= 5
mysql.one.maxActive= 20
mysql.one.maxWait= 6000
mysql.one.validationQuery= select 1 from dual
mysql.one.drever-class-name= com.mysql.jdbc.Driver

　　

public class RouteDataSource extends AbstractRoutingDataSource {
    @Override
    protected Object determineCurrentLookupKey() {
        return DataSourceContext.getDataSource();
    }
}