springboot+mysql數據源切換

數據源切換

一.這 裏我作的是mysql讀寫分離，我是創建了兩個連接，分別用了不一樣的端口號來分開（固然也能夠區分數據庫，這個根據本身所需 ）

 

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文件中鏈接的

二.接下來咱們添加工具包

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的鏈接，並提供給另一個工具包決定咱們的方法到底走application.properties中哪個鏈接

 1 package com.fh.datademo.datasoucedynamic;
 2 
 3 import org.springframework.context.annotation.Lazy;
 4 import org.springframework.stereotype.Component;
 5 
 6 /**
 7  * @author yuchunqiang
 8  * @Title: DataSourceContextHolder
 9  * @Package com.fh.datademo.datasoucedynamic
10  * @Description: ${todo}
11  * @date 2018/10/24  16:00
12  */
13 @Component
14 @Lazy(false)
15 public class DataSourceContextHolder {
16     private static final ThreadLocal<String> contextHolder = new ThreadLocal<>();
17 
18     public static void setDbType(String dbType) {
19         contextHolder.set(dbType);
20     }
21 
22     public static String getDbType() {
23         return contextHolder.get();
24     }
25 
26     public static void clearDbType() {
27         contextHolder.remove();
28     }
29 }

 

 1 package com.fh.datademo.datasoucedynamic;
 2 
 3 import org.springframework.beans.factory.annotation.Autowired;
 4 import org.springframework.beans.factory.annotation.Qualifier;
 5 import org.springframework.context.annotation.Primary;
 6 import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;
 7 import org.springframework.stereotype.Component;
 8 
 9 
10 import javax.sql.DataSource;
11 import java.util.HashMap;
12 import java.util.Map;
13 
14 /**
15  * @author yuchunqiang
16  * @Title: DynamicDataSource
17  * @Package com.fh.datademo.datasoucedynamic
18  * @Description: ${todo}
19  * @date 2018/10/24  16:06
20  */
21 @Component
22 @Primary
23 public class DynamicDataSource extends AbstractRoutingDataSource {
24 
25     @Autowired
26     @Qualifier("selectDataSource")
27     private DataSource selectDataSource;
28 
29     @Autowired
30     @Qualifier("updateDataSource")
31     private DataSource updateDataSource;
32 
33     /**
34      * 這個是主要的方法，返回的是生效的數據源名稱
35      */
36     @Override
37     protected Object determineCurrentLookupKey() {
38         System.out.println("DataSourceContextHolder：：："+DataSourceContextHolder.getDbType());
39         return DataSourceContextHolder.getDbType();
40     }
41 
42     /**
43      * 本身配的時候總是報什麼沒有指定target這裏設置一下，默認數據源是updateDataSource
44      */
45     @Override
46     public void afterPropertiesSet() {
47         Map<Object,Object> map = new HashMap<>();
48         map.put("selectDataSource",selectDataSource);
49         map.put("updateDataSource",updateDataSource);
50         setTargetDataSources(map);
51         setDefaultTargetDataSource(updateDataSource);
52         super.afterPropertiesSet();
53     }
54 }

 

 1 package com.fh.datademo.datasoucedynamic;
 2 
 3 import org.aspectj.lang.JoinPoint;
 4 import org.aspectj.lang.annotation.Aspect;
 5 import org.aspectj.lang.annotation.Before;
 6 import org.springframework.context.annotation.Lazy;
 7 import org.springframework.core.annotation.Order;
 8 import org.springframework.stereotype.Component;
 9 
10 /**
11  * @author yuchunqiang
12  * @Title: SwitchDataSourceAOP
13  * @Package com.fh.datademo.datasoucedynamic
14  * @Description: ${todo}
15  * @date 2018/10/24  15:54
16  */
17 @Aspect
18 @Component
19 @Lazy(false)
20 @Order(0) //Order設定AOP執行順序 使之在數據庫事務上先執行
21 public class SwitchDataSourceAOP {
22 
23     //這裏切到你的方法目錄
24     @Before("execution(* com.fh.datademo.service.*.*.*(..))")
25     public void process(JoinPoint joinPoint) {
26         String methodName=joinPoint.getSignature().getName();
27         if (methodName.startsWith("get")
28                 ||methodName.startsWith("count")
29                 ||methodName.startsWith("find")
30                 ||methodName.startsWith("list")
31                 ||methodName.startsWith("select")
32                 ||methodName.startsWith("check")
33                 ||methodName.startsWith("query")){
34             DataSourceContextHolder.setDbType("selectDataSource");
35         }else {
36             //切換dataSource
37             DataSourceContextHolder.setDbType("updateDataSource");
38         }
39     }
40 
41 }

 

用來在走方法以前，來決定走哪一個數據源，在@Before的設置中（@Before("execution(* com.fh.datademo.service.*.*.*(..))")）決定具體到哪一個包，具體到哪一個類，而後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，不然走寫的數據源。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