springboot + mybatisplus 配置多数据源（另一种方式）

之前的那种方式（https://blog.csdn.net/weixin_43240792/article/details/88645099）需要在service中重复写相同的方法，在每个方法上指明是用的那个数据源，现在的这种方式不需写重复的方法，只需在controller调用service方法前指明使用哪个数据源。配置如下：

package com.inspur.dsp.mybatisconfig;

import com.alibaba.druid.spring.boot.autoconfigure.DruidDataSourceBuilder;


import com.baomidou.mybatisplus.plugins.OptimisticLockerInterceptor;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionTemplate;
import org.mybatis.spring.annotation.MapperScan;

import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import com.baomidou.mybatisplus.entity.GlobalConfiguration;
import com.baomidou.mybatisplus.mapper.LogicSqlInjector;
import com.baomidou.mybatisplus.plugins.PaginationInterceptor;
import com.baomidou.mybatisplus.plugins.PerformanceInterceptor;
import org.springframework.context.annotation.Primary;

import javax.sql.DataSource;
import java.util.HashMap;
import java.util.Map;


/**
 * Mybatis配置
 * @author jamesli
 * @date 2017-05-26
 */
@EnableTransactionManagement
@Configuration
@MapperScan(basePackages = {"com.inspur.dsp.**.dao", "mapper"})    //dao、mapper路径
public class MybatisConfig {

    /**
     * mybatis-plus分页插件

     * 文档：http://mp.baomidou.com

     */
    @Bean
    public PaginationInterceptor paginationInterceptor() {
        PaginationInterceptor paginationInterceptor = new PaginationInterceptor();
        paginationInterceptor.setLocalPage(true);// 开启 PageHelper 的支持
        return paginationInterceptor;
    }


    /**
     * mybatis-plus SQL执行效率插件【生产环境可以关闭】
     */
    @Bean
    public PerformanceInterceptor performanceInterceptor() {
        return new PerformanceInterceptor();
    }

    @Bean(name="db1")
    @ConfigurationProperties("spring.datasource.druid.db1")    //需跟配置文件中的写法一样
    public DataSource db1() {
        return DruidDataSourceBuilder.create().build();
    }

    @Bean(name="db2")
    @ConfigurationProperties("spring.datasource.druid.db2")
    public DataSource db2() {
        return DruidDataSourceBuilder.create().build();
    }

    @Bean(name="db3")
    @ConfigurationProperties("spring.datasource.druid.db3")
    public DataSource db3() {
        return DruidDataSourceBuilder.create().build();
    }

    @Bean
    @Primary
    public DynamicDataSource dataSource(@Qualifier("db1") DataSource db1, @Qualifier("db2") DataSource db2,@Qualifier("db3") DataSource db3) {
        Map targetDataSources = new HashMap<>();
        targetDataSources.put(DataSourceNames.BWCONVERGE, db1);
        targetDataSources.put(DataSourceNames.DFCONVERGE, db2);
        targetDataSources.put(DataSourceNames.BWRETURN, db3);
        return new DynamicDataSource(db1, targetDataSources);
    }

    @Bean
    public SqlSessionTemplate sqlSessionTemplate(SqlSessionFactory sqlSessionFactory){
        return new SqlSessionTemplate(sqlSessionFactory);
    }

    @Bean
    public GlobalConfiguration globalConfiguration() {
        GlobalConfiguration conf = new GlobalConfiguration(new LogicSqlInjector());
        conf.setLogicDeleteValue("-1");
        conf.setLogicNotDeleteValue("1");
        conf.setIdType(0);
        //conf.setMetaObjectHandler(new MyMetaObjectHandler());
        conf.setDbColumnUnderline(true);
        conf.setRefresh(true);
        return conf;
    }

}

package com.inspur.dsp.mybatisconfig;

import org.apache.commons.lang.ArrayUtils;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.Signature;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.stereotype.Component;

import java.util.Map;

@Aspect
@Component
@Order(value = -100)    //@Order设置的足够小是为了让他先执行
public class DataSourceAspect {
    @Pointcut("execution(* com.inspur.dsp.statistics.service..*.*(..))")
    public void dataSourcePointCut() {

    }

    @Before("dataSourcePointCut()")
    public void changeDatasource(JoinPoint joinPoint){
        Object[] args = joinPoint.getArgs();
        Signature signature = joinPoint.getSignature();
        MethodSignature methodSignature = (MethodSignature) signature;
     //获取调用service方法传入的所有参数
        String[] parameterNames = methodSignature.getParameterNames();
        //int systemCode = ArrayUtils.indexOf(parameterNames, "systemCode");

        //controller调用service方法时传入的带有数据源标志的参数名，这里是param，传入的参数也应该是param
        int indexNum = ArrayUtils.indexOf(parameterNames, "param");   
        //int systemCode =Integer.valueOf(String.valueOf(systemCodemap.get("systemCode")));
        if(indexNum!=-1){
            Map systemCodemap = (Map)args[indexNum];
           //标志数据源的key
            String arg = String.valueOf(systemCodemap.get("datasource"));
            DynamicDataSource.setDataSource(arg);
        }
    }

    @After("dataSourcePointCut()")
    public void clearDatasource(){
        DynamicDataSource.clearDataSource();
    }







}

//根据传入的数据源标志匹配对应的数据源
public interface DataSourceNames {
    String DFCONVERGE="29";
    String BWCONVERGE="72";
    String BWRETURN="65";
}

package com.inspur.dsp.mybatisconfig;

import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;

import javax.sql.DataSource;
import java.util.Map;

public class DynamicDataSource extends AbstractRoutingDataSource {

    private static final ThreadLocal contextHolder = new ThreadLocal<>();
    public DynamicDataSource(DataSource defaultTargetDataSource, Map 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();
    }

}

使用方法：在controller指明【要求serviceImpl中方法接收指明数据源的参数名称必须是param（因为上面设置的是param）】