配置多数据源

Posted 2022-06-22 sun27

1.yml配置：

 

spring:
    datasource:
        his:
          driver-class-name: com.mysql.cj.jdbc.Driver
          password: aa
          jdbc-url: jdbc:mysql://aa:3306/aa?useUnlcode=1&characterEncoding=utf-8&zeroDateTimeBehavior=convertToNull&allowMultiQueries=true&remarksReporting=true&serverTimezone=GMT%2B8
          username: aa
        gym:
          driver-class-name: com.mysql.cj.jdbc.Driver
          password: bb
          jdbc-url: jdbc:mysql://bb/bb?useUnlcode=1&characterEncoding=utf-8&zeroDateTimeBehavior=convertToNull&allowMultiQueries=true&remarksReporting=true&serverTimezone=GMT%2B8
          username: bb

package com.gymexpress.histar.config;

import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
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;

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

2.多数据源配置类

/**
 * @author
 * 多数据源配置类
 */
@Configuration
public class DataSourceConfig 
    /**
     * 数据源exgym_new
     * @return
     */
    @Bean(name="dataSourceHis")
    @ConfigurationProperties(prefix = "spring.datasource.his")
    public DataSource dataSourceHis()
        return DataSourceBuilder.create().build();
    

    /**
     * 数据源gym
     * @return
     */
    @Bean(name="dataSourceGym")
    @ConfigurationProperties(prefix = "spring.datasource.gym")
    public DataSource dataSourceGym()
        return DataSourceBuilder.create().build();
    

    /**
     * 动态数据源:通过aop在不同的数据源之间动态切换
     * @return
     */
    @Primary
    @Bean(name="dynamicDataSource")
    public DataSource dynamicDataSource()
        DynamicDataSource dynamicDataSource=new DynamicDataSource();
        //默认数据源
        dynamicDataSource.setDefaultTargetDataSource(dataSourceHis());
        //配置多数据源
        Map<Object,Object> dsMap=new HashMap<>();
        dsMap.put("dataSourceHis",dataSourceHis());
        dsMap.put("dataSourceGym",dataSourceGym());
        dynamicDataSource.setTargetDataSources(dsMap);
        return dynamicDataSource;
    

    /**
     * 配置@transactional注解事务
     * @return
     */
    @Bean
    public PlatformTransactionManager transactionManager()
        return  new DataSourceTransactionManager(dynamicDataSource());
    


3.配置默认数据源

package com.gymexpress.histar.config;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class DataSourceContextHolder 

    private static final Logger LOGGER= LoggerFactory.getLogger(DataSourceContextHolder.class);

    /**
     * 默认数据源
     */
    public static final String DEFAULT_DS="dataSourceHis";

    /**

     * 当使用ThreadLocal维护变量时，ThreadLocal为每个使用该变量的线程提供独立的变量副本，

     * 所以每一个线程都可以独立地改变自己的副本，而不会影响其它线程所对应的副本。

     */
    private static final ThreadLocal<String> contextHolder=new ThreadLocal<>();

    /**
     * 设置数据库名
     * @param dbType
     */
    public static void setDB(String dbType)
        LOGGER.info("切换到"+dbType+"数据源");
        contextHolder.set(dbType);
    

    /**
     * 获取数据源名
     * @return
     */
    public static String getDB()
        return (contextHolder.get());
    

    /**
     * 清楚数据源
     */
    public static void  clearDB()
        contextHolder.remove();
    


4.自定义注解

package com.gymexpress.histar.config;

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

/**
 * @author
 * 自定义注解
 */
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
public @interface DS 

    /**
     * 默认His数据库
     * @return
     */
    String value() default "dataSourceHis";

5.获取数据源

package com.gymexpress.histar.config;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;

/**
 * @author
 *
 */
public class DynamicDataSource extends AbstractRoutingDataSource 

    private static final Logger LOGGER= LoggerFactory.getLogger(DynamicDataSource.class);

    @Override
    protected Object determineCurrentLookupKey() 
        LOGGER.info("数据源为:"+DataSourceContextHolder.getDB());
        return DataSourceContextHolder.getDB();
    

6.切换数据源

package com.gymexpress.histar.config;

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.reflect.MethodSignature;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;

import java.lang.reflect.Method;

/**
 * 自定义注解 + AOP的方式实现数据源动态切换。
 * @author
 *
 */
@Aspect
@Component
public class DynamicDataSourceAspect 
    private static final Logger LOGGER= LoggerFactory.getLogger(DynamicDataSourceAspect.class);

    @Before("@annotation(DS)")
    public void beforeSwitchDS(JoinPoint point)
        //获得当前访问的class
        Class<?> className = point.getTarget().getClass();
        //获得访问的方法名
        String name = point.getSignature().getName();
        //得到方法参数的类型
        Class[] parameterTypes = ((MethodSignature) point.getSignature()).getParameterTypes();
        String datasource = DataSourceContextHolder.DEFAULT_DS;
        try 
            //得到访问的方法对象
            Method method = className.getMethod(name, parameterTypes);
            //判断是否存在@DS注解
            if(method.isAnnotationPresent(DS.class))
                DS annotation = method.getAnnotation(DS.class);
                //取出注解中的数据源名
                datasource = annotation.value();
            
        catch (Exception e)
            LOGGER.error(e.toString(),e);

        
        //切换数据源
        DataSourceContextHolder.setDB(datasource);
    

    @After("@annotation(DS)")
    public void afterSwitchDs(JoinPoint joinPoint)
        DataSourceContextHolder.clearDB();