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=true
- username: root
- password: admin
- sql-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
- @EnableTransactionManagement
- publicclassDataSourceConfig{
- @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>
- @Override
- publicConnection getConnection() throwsSQLException{
- return dataSourceMap.get("1").getConnection();
- }
- @Override
- publicConnection 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;
- @RestController
- publicclassHikariCpController{
- @Autowired
- privateUserInfoMapper mapper;
- @Autowired
- privateHikariCPDataSourceFactory 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
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