本篇内容主要讲解“SpringBoot多数据源切换怎么实现”，感兴趣的朋友不妨来看看。本文介绍的方法操作简单快捷，实用性强。下面就让小编来带大家学习“SpringBoot多数据源切换怎么实现”吧!
配置文件(YML)
spring: datasource: default-db-key: voidme multi-db: - voidme: driver-class-name: com.mysql.cj.jdbc.Driver username: root password: root url: jdbc:mysql://192.168.42.153:3306/voidme?characterEncoding=utf8&autoReconnect=true&failOverReadOnly=false&maxReconnects=10&useSSL=false - xcdef: driver-class-name: com.mysql.cj.jdbc.Driver username: root password: root url: jdbc:mysql://192.168.42.153:3306/xcdef?characterEncoding=utf8&autoReconnect=true&failOverReadOnly=false&maxReconnects=10&useSSL=falsemybatis: #1.classpath：只会到你的classes路径中查找找文件。 #2.classpath*：不仅会到classes路径，还包括jar文件中(classes路径)进行查找。 mapper-locations: classpath*:/mapper*Mapper.xml # mapper映射文件位置 type-aliases-package: com.**.entity # 实体类所在的位置 configuration: log-impl: org.apache.ibatis.logging.stdout.StdOutImpl #用于控制台打印sql语句 map-underscore-to-camel-case: true #开启将带有下划线的表字段 映射为驼峰格式的实体类属性核心代码
DynamicDataSource
这个类用于获取数据源的(核心)
package com.dynamicdatadource.dynamic;import org.springframework.beans.factory.annotation.Value;import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;public class DynamicDataSource extends AbstractRoutingDataSource { @Value("${spring.datasource.default-db-key}") private String defaultDbKey; @Override protected Object determineCurrentLookupKey() { String currentDb = DynamicDataSourceService.currentDb(); if (currentDb == null) { return defaultDbKey; } return currentDb; }}DynamicDataSourceService
这个类是数据源切换工具,我们做了线程隔离了所以不用担心多线程数据源会混乱的问题
package com.dynamicdatadource.dynamic;import com.application.ApplicationContextProvider;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.boot.jdbc.DataSourceBuilder;import javax.sql.DataSource;import java.util.HashMap;import java.util.Map;public class DynamicDataSourceService { private static final Logger log = LoggerFactory.getLogger(DynamicDataSourceService.class); private static final Map<Object, Object> dataSources = new HashMap<>(); private static final ThreadLocal<String> dbKeys = ThreadLocal.withInitial(() -> null); public static void addDataSource(String name, DataSource dataSource) { DynamicDataSource dynamicDataSource = ApplicationContextProvider.getApplicationContext().getBean(DynamicDataSource.class); dataSources.put(name, dataSource); dynamicDataSource.setTargetDataSources(dataSources); dynamicDataSource.afterPropertiesSet(); log.info("添加了数据源:{}",name); } public static void addDataSource(String name, String driverClassName,String url,String username,String password) { DataSourceBuilder<?> builder = DataSourceBuilder.create(); builder.driverClassName(driverClassName); builder.username(username); builder.password(password); builder.url(url); addDataSource(name,builder.build()); log.info("添加了数据源:{}",name); } public static void switchDb(String dbKey) { dbKeys.set(dbKey); } public static void resetDb() { dbKeys.remove(); } public static String currentDb() { return dbKeys.get(); }}DynamicDataSourceConfig
将数据源配置到springboot中和初始化Mybaitis配置
package com.dynamicdatadource.dynamic;import lombok.Data;import org.apache.ibatis.logging.Log;import org.mybatis.spring.SqlSessionFactoryBean;import org.springframework.boot.context.properties.ConfigurationProperties;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;import org.springframework.core.io.support.PathMatchingResourcePatternResolver;import org.springframework.jdbc.datasource.DataSourceTransactionManager;import org.springframework.transaction.PlatformTransactionManager;import java.io.IOException;import java.util.HashMap;import java.util.Map;@Configuration@ConfigurationProperties(prefix = "mybatis")@Datapublic class DynamicDataSourceConfig { private String mapperLocations; private String typeAliasesPackage; @Data public class MybatisConfiguration{ private String logImpl; private boolean mapUnderscoreToCamelCase; } private MybatisConfiguration configuration=new MybatisConfiguration(); @Bean public DynamicDataSource dynamicDataSource() { DynamicDataSource dataSource = new DynamicDataSource(); Map<Object, Object> targetDataSources = new HashMap<>(); dataSource.setTargetDataSources(targetDataSources); return dataSource; } @Bean public SqlSessionFactoryBean sqlSessionFactoryBean() throws IOException, ClassNotFoundException { org.apache.ibatis.session.Configuration configuration = new org.apache.ibatis.session.Configuration(); configuration.setMapUnderscoreToCamelCase(this.configuration.isMapUnderscoreToCamelCase()); //开启驼峰命名 configuration.setLogImpl((Class<? extends Log>) Class.forName(this.configuration.getLogImpl())); //控制台打印sql日志 SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean(); sqlSessionFactoryBean.setDataSource(dynamicDataSource()); sqlSessionFactoryBean.setConfiguration(configuration); PathMatchingResourcePatternResolver resolver = new PathMatchingResourcePatternResolver(); sqlSessionFactoryBean.setMapperLocations(resolver.getResources(mapperLocations)); sqlSessionFactoryBean.setTypeAliasesPackage(typeAliasesPackage); return sqlSessionFactoryBean; } @Bean public PlatformTransactionManager transactionManager() { return new DataSourceTransactionManager(dynamicDataSource()); }}加载YML数据库配置类
package com.dynamicdatadource.config;import com.dynamicdatadource.dynamic.DynamicDataSourceService;import lombok.Data;import org.springframework.boot.autoconfigure.jdbc.DataSourceProperties;import org.springframework.boot.context.properties.ConfigurationProperties;import org.springframework.boot.jdbc.DataSourceBuilder;import org.springframework.stereotype.Component;import javax.annotation.PostConstruct;import javax.sql.DataSource;import java.util.List;import java.util.Map;import java.util.Set;@Component@Data@ConfigurationProperties(prefix = "spring.datasource")public class YmlDataSourceProvider { private List<Map<String, DataSourceProperties>> multiDb; private DataSource buildDataSource(DataSourceProperties prop) { DataSourceBuilder<?> builder = DataSourceBuilder.create(); builder.driverClassName(prop.getDriverClassName()); builder.username(prop.getUsername()); builder.password(prop.getPassword()); builder.url(prop.getUrl()); return builder.build(); } public void initDataSource() { multiDb.forEach(map -> { Set<String> keys = map.keySet(); keys.forEach(key -> { DataSourceProperties properties = map.get(key); DataSource dataSource = buildDataSource(properties); DynamicDataSourceService.addDataSource(key, dataSource); }); }); } //在构造函数之后执行 @PostConstruct public void init() { initDataSource(); }}aop切换
package com.dynamicdatadource.aop;import java.lang.annotation.ElementType;import java.lang.annotation.Retention;import java.lang.annotation.RetentionPolicy;import java.lang.annotation.Target;@Target({ElementType.METHOD,ElementType.TYPE})//作用:方法和类@Retention(RetentionPolicy.RUNTIME)public @interface DynamicDataSourceAnno { String key() default "";}package com.dynamicdatadource.aop;import com.dynamicdatadource.dynamic.DynamicDataSourceService;import org.apache.commons.lang.StringUtils;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.stereotype.Component;// 用于单独的请求或者类进行切换数据库@Aspect@Componentpublic class DynamicDataSourceAspect { @Pointcut("@annotation(com.dynamicdatadource.aop.DynamicDataSourceAnno)") public void dynamicDataSourceAnno() { } @Around("dynamicDataSourceAnno()") public Object DynamicDataSourceAspectAroundAnno(ProceedingJoinPoint joinPoint) { Object object = null; try { MethodSignature signature = (MethodSignature)joinPoint.getSignature(); DynamicDataSourceAnno dynamicDataSourceAnno = signature.getMethod().getAnnotation(DynamicDataSourceAnno.class); String key = dynamicDataSourceAnno.key(); if (StringUtils.isNotBlank(key)) { //切换为指定数据库 DynamicDataSourceService.switchDb(key); } object = joinPoint.proceed(); } catch (Throwable e) { e.printStackTrace(); }finally { //还原为默认配置 DynamicDataSourceService.resetDb(); } return object; } // 还可以扩展包路径切换}效果
运行程序之后,就会将数据源加入到数据源列表中了
扩展
MysqlDataSourceInitialize
从数据库中将配置信息查询出来,然后动态添加到数据源列表中
package com.dao.config;import com.dao.DatasourceDao;import com.dynamicdatadource.aop.DynamicDataSourceAnno;import com.dynamicdatadource.dynamic.DynamicDataSourceService;import com.entity.DataSourceEneity;import org.springframework.beans.factory.InitializingBean;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.boot.ApplicationArguments;import org.springframework.boot.ApplicationRunner;import org.springframework.stereotype.Component;import javax.annotation.PostConstruct;import javax.sql.DataSource;import java.util.List;//从数据库中查询出全部的数据源,添加到数据源容器中@Componentpublic class MysqlDataSourceInitialize implements ApplicationRunner { @Autowired private DatasourceDao datasourceDao; //项目启动后执行初始化数据源 @Override public void run(ApplicationArguments args) throws Exception { try { List<DataSourceEneity> dataSources = datasourceDao.getDataSources(); for (DataSourceEneity dataSource : dataSources) { DynamicDataSourceService.addDataSource(dataSource.getKey(),dataSource.getDataSource()); } } catch (Exception e) { e.printStackTrace(); } }}DataSourceEneity实体类
@Datapublic class DataSourceEneity { private int id; private String key; private String url; private String username; private String password; private String driverClassName; private String type; private int state; public DataSource getDataSource() { DataSourceBuilder<?> builder = DataSourceBuilder.create(); builder.driverClassName(driverClassName); builder.username(username); builder.password(password); builder.url(url); return builder.build(); }}到此，相信大家对“SpringBoot多数据源切换怎么实现”有了更深的了解，不妨来实际操作一番吧！这里是编程网网站，更多相关内容可以进入相关频道进行查询，关注我们，继续学习！
