一, 引入Jar包:

<dependency> <!-- MySql驱动 -->
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    </dependency>
<dependency> <!-- 连接池 -->
    <groupId>com.alibaba</groupId>
    <artifactId>druid-spring-boot-starter</artifactId>
    <version>1.1.9</version>
</dependency>

二, 配置参数:

spring:
    datasource:
        type: com.alibaba.druid.pool.DruidDataSource
        driverClassName: com.mysql.jdbc.Driver
        druid:
            one:  #数据源1
                url: jdbc:mysql://localhost:3306/test1?...
                username: root
                password: root
            two: #数据源2
                url: jdbc:mysql://localhost:3306/test2?...
                username: root
                password: root
            initial-size: 10
            max-active: 100
            min-idle: 10
            max-wait: 60000
            pool-prepared-statements: true
            max-pool-prepared-statement-per-connection-size: 20
            time-between-eviction-runs-millis: 60000
            min-evictable-idle-time-millis: 300000
            validation-query: SELECT 1 FROM DUAL
            test-while-idle: true
            test-on-borrow: false
            test-on-return: false
            stat-view-servlet:
                enabled: true
                url-pattern: /druid/*
                #login-username: admin
                #login-password: admin
            filter:
                stat:
                    log-slow-sql: true
                    slow-sql-millis: 1000
                    merge-sql: true
                wall:
                    config:
                        multi-statement-allow: true

(参数配置,可参考:  https://gitee.com/wenshao/druid/tree/master/druid-spring-boot-starter)

三, 编写配置文件:

1,  定义数据源名称常量 : 

package com.wqy.config.data;

/**
 * 数据源名称
 * @author wqy
 * @date 2019-11-28
 */
public interface DataSourceNames {
    String ONE = "ONE";
    String TWO = "TWO";
}

2,  创建动态数据源:

package com.wqy.config.data;

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

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

/**
 * 动态数据源
 * @author wqy
 * @date 2019-11-28
 */
public class DynamicDataSource extends AbstractRoutingDataSource {
    private static final ThreadLocal<String> contextHolder = new ThreadLocal<>();

    /**
     * 配置DataSource, defaultTargetDataSource为主数据库
     */
    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();
    }

}

3, 动态数据源配置:

package com.wqy.config.data;

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

/**
 * 配置多数据源
 * @author wqy
 * @date 2019-11-28
 */
@Configuration
public class DynamicDataSourceConfig {

    /**
     * 创建 DataSource Bean
     * */

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

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

    /**
     * 如果还有数据源,在这继续添加 DataSource Bean
     * */

    @Bean
    @Primary
    public DynamicDataSource dataSource(DataSource oneDataSource, DataSource twoDataSource) {
        Map<Object, Object> targetDataSources = new HashMap<>(2);
        targetDataSources.put(DataSourceNames.ONE, oneDataSource);
        targetDataSources.put(DataSourceNames.TWO, twoDataSource);
        // 还有数据源,在targetDataSources中继续添加
        System.out.println("DataSources:" + targetDataSources);
        return new DynamicDataSource(oneDataSource, targetDataSources);
    }
}

4, 定义动态数据源注解:

package com.wqy.config.data;

import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * 多数据源注解
 * @author wqy
 * @date 2019-11-28
 */
@Documented
@Target({ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
public @interface DataSource {
    String value() default DataSourceNames.ONE;
}

5, 设置数据源 AOP 代理:

package com.wqy.config.data;

import java.lang.reflect.Method;

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.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.core.Ordered;
import org.springframework.stereotype.Component;

/**
 * 数据源AOP切面处理
 * @author wqy
 * @date 2019-11-28
 */
@Aspect
@Component
public class DataSourceAspect implements Ordered {
    protected Logger logger = LoggerFactory.getLogger(getClass());

    /**
     * 切点: 所有配置 DataSource 注解的方法
     */
    @Pointcut("@annotation(com.gy.fast.common.config.data.DataSource)")
    public void dataSourcePointCut() {}

    @Around("dataSourcePointCut()")
    public Object around(ProceedingJoinPoint point) throws Throwable {
        MethodSignature signature = (MethodSignature) point.getSignature();
        Method method = signature.getMethod();
        DataSource ds = method.getAnnotation(DataSource.class);
        // 通过判断 DataSource 中的值来判断当前方法应用哪个数据源
        DynamicDataSource.setDataSource(ds.value());
        System.out.println("当前数据源: " + ds.value());
        logger.debug("set datasource is " + ds.value());
        try {
            return point.proceed();
        } finally {
            DynamicDataSource.clearDataSource();
            logger.debug("clean datasource");
        }
    }

    @Override
    public int getOrder() {
        return 1;
    }
}

四, 修改启动文件:

package com.wqy.fast;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
import org.springframework.context.annotation.Import;

import com.gy.fast.common.config.data.DynamicDataSourceConfig;


/**
 * 动态数据源配置,需要将自有的配置依赖(DynamicDataSourceConfig),将原有的依赖去除(DataSourceAutoConfiguration)
 * @author wqy
 * @date 2019-11-28
 */
@Import({DynamicDataSourceConfig.class})
@SpringBootApplication(exclude={DataSourceAutoConfiguration.class})
public class FastApplication {
    public static void main(String[] args) {
        SpringApplication.run(FastApplication.class, args);
    }
}

五, 配置完成, 进行测试:

package com.wqy.fast;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.gy.fast.common.config.data.DataSource;
import com.gy.fast.common.config.data.DataSourceNames;
import com.gy.fast.module.sys.entity.SysUser;
import com.gy.fast.module.sys.service.SysUserService;

/**
 * 测试多数据源
 * @author wqy
 * @date 2019-11-28
 */
@Service
public class DataSourceTestService {
    @Autowired
    private SysUserService sysUserService;

    public SysUser test1(Long userId){
        return sysUserService.selectById(userId);
    }

    @DataSource(DataSourceNames.TWO)
    public SysUser test2(Long userId){
        return sysUserService.selectById(userId);
    }
}
package com.wqy.fast;


import org.apache.commons.lang3.builder.ToStringBuilder;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

import com.gy.fast.module.sys.entity.SysUser;

@RunWith(SpringRunner.class)
@SpringBootTest
public class DynamicDataSourceTest {
    @Autowired
    private DataSourceTestService dataSourceTestService;

    @Test
    public void test(){
        // 数据源ONE
        SysUser user1 = dataSourceTestService.test1(1L);
        System.out.println(ToStringBuilder.reflectionToString(user1));

        // 数据源TWO
        SysUser user2 = dataSourceTestService.test2(1L);
        System.out.println(ToStringBuilder.reflectionToString(user2));

        // 数据源ONE
        SysUser user3 = dataSourceTestService.test1(1L);
        System.out.println(ToStringBuilder.reflectionToString(user3));
    }

}

原创文件摘自:https://my.oschina.net/u/3681868/blog/1813011

12-17 10:01