springboot+mysql數據源切換

數據源切換

一.這 里我做的是mysql讀寫分離，我是建立了兩個鏈接，分別用了不同的端口號來分開（當然也可以區分數據庫，這個根據自己所需 ）

 

spring.datasource.select.jdbc-url=jdbc:mysql://localhost:3308/product
spring.datasource.select.username=root
spring.datasource.select.password=
spring.datasource.select.driver-class-name=com.mysql.jdbc.Driver


spring.datasource.update.jdbc-url=jdbc:mysql://localhost:3307/product
spring.datasource.update.username=root
spring.datasource.update.password=
spring.datasource.update.driver-class-name=com.mysql.jdbc.Driver
#加載mapper文件
mybatis.mapper-locations=classpath*:mapper/*.xml
#修改訪問端口
server.port=8099

 

 

這個是在springboot項目中的，application.properties文件中連接的

二.接下來我們添加工具包

package com.fh.datademo.datasoucedynamic;

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 javax.sql.DataSource;

/**
 * @author yuchunqiang
 * @Title: DataSourceConfig
 * @Package com.fh.datademo.datasoucedynamic
 * @Description: ${todo}
 * @date 2018/10/24  16:01
 */
@Configuration
public class DataSourceConfig {
    @Bean(name = "selectDataSource")
    @ConfigurationProperties(prefix = "spring.datasource.select")
    public DataSource dataSource1() {
        return DataSourceBuilder.create().build();
    }

    @Bean(name = "updateDataSource")
    @ConfigurationProperties(prefix = "spring.datasource.update")
    public DataSource dataSource2() {
        return DataSourceBuilder.create().build();
    }

}

 

這個主要用來找到兩個mysql的連接，並提供給另外一個工具包決定我們的方法到底走application.properties中哪一個連接

package com.fh.datademo.datasoucedynamic;

import org.springframework.context.annotation.Lazy;
import org.springframework.stereotype.Component;

/**
 * @author yuchunqiang
 * @Title: DataSourceContextHolder
 * @Package com.fh.datademo.datasoucedynamic
 * @Description: ${todo}
 * @date 2018/10/24  16:00
 */
@Component
@Lazy(false)
public class DataSourceContextHolder {
    private static final ThreadLocal<String> contextHolder = new ThreadLocal<>();

    public static void setDbType(String dbType) {
        contextHolder.set(dbType);
    }

    public static String getDbType() {
        return contextHolder.get();
    }

    public static void clearDbType() {
        contextHolder.remove();
    }
}

 

package com.fh.datademo.datasoucedynamic;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.context.annotation.Primary;
import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;
import org.springframework.stereotype.Component;


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

/**
 * @author yuchunqiang
 * @Title: DynamicDataSource
 * @Package com.fh.datademo.datasoucedynamic
 * @Description: ${todo}
 * @date 2018/10/24  16:06
 */
@Component
@Primary
public class DynamicDataSource extends AbstractRoutingDataSource {

    @Autowired
    @Qualifier("selectDataSource")
    private DataSource selectDataSource;

    @Autowired
    @Qualifier("updateDataSource")
    private DataSource updateDataSource;

    /**
     * 這個是主要的方法，返回的是生效的數據源名稱
     */
    @Override
    protected Object determineCurrentLookupKey() {
        System.out.println("DataSourceContextHolder：：："+DataSourceContextHolder.getDbType());
        return DataSourceContextHolder.getDbType();
    }

    /**
     * 自己配的時候老是報什么沒有指定target這里設置一下，默認數據源是updateDataSource
     */
    @Override
    public void afterPropertiesSet() {
        Map<Object,Object> map = new HashMap<>();
        map.put("selectDataSource",selectDataSource);
        map.put("updateDataSource",updateDataSource);
        setTargetDataSources(map);
        setDefaultTargetDataSource(updateDataSource);
        super.afterPropertiesSet();
    }
}

 

package com.fh.datademo.datasoucedynamic;

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.springframework.context.annotation.Lazy;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;

/**
 * @author yuchunqiang
 * @Title: SwitchDataSourceAOP
 * @Package com.fh.datademo.datasoucedynamic
 * @Description: ${todo}
 * @date 2018/10/24  15:54
 */
@Aspect
@Component
@Lazy(false)
@Order(0) //Order設定AOP執行順序 使之在數據庫事務上先執行
public class SwitchDataSourceAOP {

    //這里切到你的方法目錄
    @Before("execution(* com.fh.datademo.service.*.*.*(..))")
    public void process(JoinPoint joinPoint) {
        String methodName=joinPoint.getSignature().getName();
        if (methodName.startsWith("get")
                ||methodName.startsWith("count")
                ||methodName.startsWith("find")
                ||methodName.startsWith("list")
                ||methodName.startsWith("select")
                ||methodName.startsWith("check")
                ||methodName.startsWith("query")){
            DataSourceContextHolder.setDbType("selectDataSource");
        }else {
            //切換dataSource
            DataSourceContextHolder.setDbType("updateDataSource");
        }
    }

}

 

用來在走方法之前，來決定走哪個數據源，在@Before的設置中（@Before("execution(* com.fh.datademo.service.*.*.*(..))")）決定具體到哪個包，具體到哪個類，然后獲取其方法名來判斷，方法名中包含所規定的字符，則走讀的數據源，否則走寫的數據源。從而來達到讀寫分離，實現自動切換的功能

項目git地址：https://github.com/yuchunqiang