Springboot-HikariCP 实现动态数据源切换

作者丨网络抖动 原文地址https://www.jianshu.com/p/05a8a1a2b50cgitHub

项目地址：https://github.com/shizhenshuang123/hikaricp-demo

开发环境：

jdk：JDK1.8+gradle：Gradle4.6+Spring：2.1.3.RELEASE+

当数据库数据达到一定数量的时候，数据库的响应将会有所缓慢，一般都会采取一些措施。例如，读写分离、分表分库、主从服务、缓存技术等等。这里采用的是多库多表。test 库中 user_info 表：

test2 库中 user_info 表：

导入依赖

compile group: 'org.springframework.boot', name: 'spring-boot-starter-web', version: '2.1.3.RELEASE'compile group: 'org.springframework.boot', name: 'spring-boot-starter-jdbc', version: '2.1.3.RELEASE'compileOnly group: 'org.projectlombok', name: 'lombok', version: '1.18.6'compile group: 'mysql', name: 'mysql-connector-java', version: '8.0.15'compile group: 'org.mybatis.generator', name: 'mybatis-generator-core', version: '1.3.5'compile group: 'tk.mybatis', name: 'mapper', version: '4.0.2'compile group: 'org.mybatis.spring.boot', name: 'mybatis-spring-boot-starter', version: '2.0.0'

HikariCP 在 spring-boot-starter-jdbc 中已经被引入（Spring 默认数据源）

项目结构

配置文件配置（application.yaml）默认数据源信息

spring:datasource:url: jdbc:mysql://127.0.0.1:3306/test?useUnicode=true&characterEncoding=utf-8&zeroDateTimeBehavior=CONVERT_TO_NULL&serverTimezone=Asia/Shanghai&allowMultiQueries=trueusername: rootpassword: adminsql-script-encoding: UTF-8

读取配置信息 DataSourceConfig.java，创建默认的数据源

package utry.hikaricp.config;import com.zaxxer.hikari.HikariDataSource;import org.springframework.beans.factory.annotation.Value;import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;import org.springframework.transaction.annotation.EnableTransactionManagement;import utry.hikaricp.DataSourceProvider;import utry.hikaricp.info.DataSourceInfo;import utry.hikaricp.source.MyHikariDataSource;@Configuration@EnableTransactionManagementpublicclassDataSourceConfig{@Value("${spring.datasource.url}")privateString url;@Value("${spring.datasource.username}")privateString userName;@Value("${spring.datasource.password}")privateString password;@Bean@ConditionalOnMissingBean(MyHikariDataSource.class)publicMyHikariDataSource dataSource() {DataSourceInfo info = newDataSourceInfo();info.setUrl(url);info.setUsername(userName);info.setPassword(password);HikariDataSource dataSource = DataSourceProvider.create(info);MyHikariDataSource hikariCPDataSource = newMyHikariDataSource();hikariCPDataSource.updateDataSourceMap("1", dataSource);return hikariCPDataSource;}}

通过 DataSourceProvider 创建 HikariDataSource

package utry.hikaricp;import com.zaxxer.hikari.HikariConfig;import com.zaxxer.hikari.HikariDataSource;import utry.hikaricp.info.DataSourceInfo;publicclassDataSourceProvider{publicstaticHikariDataSource create(DataSourceInfo sourceInfo) {HikariConfig hikariConfig = newHikariConfig();hikariConfig.setUsername(sourceInfo.getUsername());hikariConfig.setPassword(sourceInfo.getPassword());hikariConfig.setJdbcUrl(sourceInfo.getUrl());hikariConfig.setDriverClassName("com.mysql.jdbc.Driver");returnnewHikariDataSource(hikariConfig);}}

最核心的数据源的类 MyHikariDataSource.java

package utry.hikaricp.source;import com.zaxxer.hikari.HikariDataSource;import org.springframework.jdbc.datasource.AbstractDataSource;import javax.sql.DataSource;import java.io.Closeable;import java.io.IOException;import java.sql.Connection;import java.sql.SQLException;import java.util.HashMap;import java.util.Map;publicclassMyHikariDataSourceextendsAbstractDataSource{privatestaticMap<string> dataSourceMap = newHashMap<>(1);/<string>@OverridepublicConnection getConnection() throwsSQLException{return dataSourceMap.get("1").getConnection();}@OverridepublicConnection getConnection(String username, String password) throwsSQLException{return dataSourceMap.get("1").getConnection(username, password);}privatevoid destroy(){DataSource dataSource = dataSourceMap.get("1");Closeable closeable = (Closeable) dataSource;if(closeable != null) {try{closeable.close();} catch(IOException e) {e.printStackTrace();}}}publicvoid updateDataSourceMap(String key, HikariDataSource value) {destroy();dataSourceMap.put(key, value);}}

只要将上面这个类中的 DataSourceMap 集合中的 HikariDataSource 修改就能实现数据源的切换了，调用 updateDataSourceMap() 方法修改即可（修改之前，先关闭之前的数据源，这里写死的 map 中 key=1，读者可以实现动态设置）

实体类 UserInfo.java

package utry.hikaricp.model;publicclassUserInfo{privateInteger id;privateString remarks;publicUserInfo() {}publicUserInfo(Integer id, String remarks) {this.id = id;this.remarks = remarks;}publicInteger getId() {return id;}publicvoid setId(Integer id) {this.id = id;}publicString getRemarks() {return remarks;}publicvoid setRemarks(String remarks) {this.remarks = remarks;}}

HikariCpController.java 两个接口：

更新数据源查询用户信息package utry.hikaricp.controller;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RestController;import utry.hikaricp.factory.HikariCPDataSourceFactory;import utry.hikaricp.mapper.UserInfoMapper;import utry.hikaricp.model.UserInfo;@RestControllerpublicclassHikariCpController{@AutowiredprivateUserInfoMapper mapper;@AutowiredprivateHikariCPDataSourceFactory factory;@RequestMapping("update")publicvoid info(String username, String password, String url) {factory.reload(username, password, url);}@RequestMapping("get")publicUserInfoget() {try{UserInfo userInfo = mapper.selectByPrimaryKey(1);return userInfo;} catch(Exception e) {e.printStackTrace();}returnnull;}}

启动项目

1、调用 get 接口，返回的数据是 test 库中的

2、调用 update 请求更新数据源

调用成功之后，可以看到，之前的数据源已经被 shutdown，初始化了一个新的数据源

3、再次调用 get 请求，可以看到获取的 test2 数据库中的数据