最近有個老項目想逐步將新業務的數據放到新的數據庫，以前的業務還得連接以前的數據庫，于是需要整合多數據源 。

多數據源實際上是繼承了AbstractRoutingDataSource類，這個類最終實現了DataSource接口，DataSource里只有一個getConnection方法，數據庫每次訪問的時候都要先通過這個方法獲取連接，所有多數據源就是每次訪問數據庫之前動態的改變數據源。

在請求前改變數據源當然需要用到SpringAOP，自定義注解操作

項目結構

下面上代碼：

首先是依賴：

<!--數據庫連接--> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-jdbc</artifactId> </dependency> <!--sqlserver--> <dependency> <groupId>com.microsoft.sqlserver</groupId> <artifactId>mssql-jdbc</artifactId> <scope>runtime</scope> </dependency> <!--mybatis-plus--> <dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus-boot-starter</artifactId> <version>3.1.2</version> </dependency> <!--數據庫連接池--> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>1.1.8</version> </dependency><!--AOP--> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-aop</artifactId> </dependency>

yml配置數據源

server: port: 8888spring: jackson: time-zone: GMT+8 date-format: yyyy-MM-dd HH:mm:ss datasource: druid: first: driver-class-name: com.mysql.cj.jdbc.Driver type: com.alibaba.druid.pool.DruidDataSource jdbc-url: jdbc:mysql://rm-uf6265pj340sc9447oo.mysql.rds.54565.com:3306/dm?serverTimezone=Asia/Shanghai&useSSL=false&allowPublicKeyRetrieval=true&characterEncoding=utf-8 username: username password: password second: type: com.alibaba.druid.pool.DruidDataSource driver-class-name: com.microsoft.sqlserver.jdbc.SQLServerDriver jdbc-url: jdbc:sqlserver://39.104.203.222:1433;DatabaseName=TestTLcom username: root password: 123456mybatis-plus: mapper-locations: classpath*:/mapper/*Mapper.xml type-aliases-package: com.zdyl.dynamicdatasourcedemo.entity global-config: #主鍵類型 0:'數據庫ID自增', 1:'用戶輸入ID',2:'全局唯一ID (數字類型唯一ID)', 3:'全局唯一ID UUID'; id-type: 3 #字段策略 0:'忽略判斷',1:'非 NULL 判斷'),2:'非空判斷' field-strategy: 2 #駝峰下劃線轉換 db-column-underline: true #刷新mapper 調試神器 refresh-mapper: true #數據庫大寫下劃線轉換 #capital-mode: true #序列接口實現類配置 #key-generator: com.baomidou.springboot.xxx #邏輯刪除配置 #logic-delete-value: 0 #logic-not-delete-value: 1 #自定義填充策略接口實現 #meta-object-handler: com.baomidou.springboot.xxx #自定義SQL注入器 #sql-injector: com.baomidou.springboot.xxx configuration: map-underscore-to-camel-case: true cache-enabled: false

定義數據庫名稱

/** * 數據庫名稱 */public interface DataSourceNames { String FIRST = 'first'; String SECOND = 'second';}

動態數據源

import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;import javax.sql.DataSource;import java.util.HashMap;import java.util.Map;/** * 動態數據源 */public class DynamicDataSource extends AbstractRoutingDataSource { private static final ThreadLocal<String> contextHolder = new ThreadLocal<>(); public DynamicDataSource(DataSource defaultTargetDataSource, Map<String, DataSource> targetDataSources) { super.setDefaultTargetDataSource(defaultTargetDataSource); super.setTargetDataSources(new HashMap<>(targetDataSources)); super.afterPropertiesSet(); } @Override protected Object determineCurrentLookupKey() { return getDataSource(); } public static String getDataSource() { return contextHolder.get(); } public static void setDataSource(String dataSource) { contextHolder.set(dataSource); } public static void clearDataSource() { contextHolder.remove(); }}

配置多數據源

import com.baomidou.mybatisplus.extension.plugins.PaginationInterceptor;import com.zdyl.dynamicdatasourcedemo.dynamicdatasource.DataSourceNames;import com.zdyl.dynamicdatasourcedemo.dynamicdatasource.DynamicDataSource;import org.mybatis.spring.annotation.MapperScan;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 javax.sql.DataSource;import java.util.HashMap;import java.util.Map;/** * 多數據源配置 */@Configuration@MapperScan('com.zdyl.dynamicdatasourcedemo.**.mapper*')public class MybatisPluConfig { /** * 數據源配置 * @return */ @Bean @ConfigurationProperties(prefix='spring.datasource.druid.first') public DataSource firstDataSource() { return DataSourceBuilder.create().build(); } @Bean @ConfigurationProperties(prefix='spring.datasource.druid.second') public DataSource secondDataSource() { return DataSourceBuilder.create().build(); } @Bean @Primary public DynamicDataSource dataSource(DataSource firstDataSource, DataSource secondDataSource){ Map<String, DataSource> targetDataSources = new HashMap<>(); targetDataSources.put(DataSourceNames.FIRST, firstDataSource); targetDataSources.put(DataSourceNames.SECOND, secondDataSource); return new DynamicDataSource(firstDataSource, targetDataSources); } /** * mybatis-plus分頁插件<br> * 文檔：http://mp.baomidou.com<br> */ @Bean public PaginationInterceptor paginationInterceptor() { return new PaginationInterceptor(); }}

下面就是自定義注解

import java.lang.annotation.*;/** * 多數據源注解 * AOP攔截此注解更換數據源 */@Target(ElementType.METHOD)@Retention(RetentionPolicy.RUNTIME)@Documentedpublic @interface CurDataSource { String name() default '';}

AOP

import com.zdyl.dynamicdatasourcedemo.dynamicdatasource.DataSourceNames;import com.zdyl.dynamicdatasourcedemo.dynamicdatasource.DynamicDataSource;import com.zdyl.dynamicdatasourcedemo.dynamicdatasource.annotation.CurDataSource;import lombok.extern.slf4j.Slf4j;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.springframework.core.Ordered;import org.springframework.stereotype.Component;import java.lang.reflect.Method;/** * 多數據源，切面處理類 * AOP攔截多數據源注解 @CurDataSource 注解更換數據源 */@Slf4j@Aspect@Componentpublic class DataSourceAspect implements Ordered { /** * 切點 */ @Pointcut('@annotation(com.zdyl.dynamicdatasourcedemo.dynamicdatasource.annotation.CurDataSource)') public void dataSourcePointCut() { } @Around('dataSourcePointCut()') public Object around(ProceedingJoinPoint point) throws Throwable { MethodSignature signature = (MethodSignature) point.getSignature(); Method method = signature.getMethod(); CurDataSource curDataSource = method.getAnnotation(CurDataSource.class); if (curDataSource == null) { DynamicDataSource.setDataSource(DataSourceNames.FIRST); log.info('set datasource is ' + DataSourceNames.FIRST); } else { DynamicDataSource.setDataSource(curDataSource.name()); log.info('set datasource is ' + curDataSource.name()); } try { return point.proceed(); } finally { DynamicDataSource.clearDataSource(); log.info('clean datasource'); } } @Override public int getOrder() { return 1; }}

最后主啟動了去掉數據源自動加載

@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)

最后我們來跑起來請求一下，測試一下是否正確

@RestControllerpublic class CfgDeviceController { @Resource CfgDeviceService cfgDeviceService; @Resource CfgChargeStartInfoService cfgChargeStartInfoService; @CurDataSource(name = DataSourceNames.FIRST) @GetMapping('/test') public void getUser() { CfgDevice byId = cfgDeviceService.getById(19); System.out.println(byId.toString()); } @CurDataSource(name = DataSourceNames.SECOND) @GetMapping('/test1') public void getUser1() { CfgChargeStartInfo byId = cfgChargeStartInfoService.getById(1); System.out.println(byId.toString()); }}

**如果不加注解，使用默認數據源

至此就整合完了

以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持好吧啦網。