Springboot-HikariCP 實現動態數據源切換

作者丨網絡抖動 原文地址https://www.jianshu.com/p/05a8a1a2b50cgitHub

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

開發環境：

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

當數據庫數據達到一定數量的時候，數據庫的響應將會有所緩慢，一般都會採取一些措施。例如，讀寫分離、分表分庫、主從服務、緩存技術等等。這裡採用的是多庫多表。test 庫中 user_info 表：

test2 庫中 user_info 表：

導入依賴

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

HikariCP 在 spring-boot-starter-jdbc 中已經被引入（Spring 默認數據源）

項目結構

配置文件配置（application.yaml）默認數據源信息

1. spring:
2. datasource:
3. url: jdbc:mysql://127.0.0.1:3306/test?useUnicode=true&characterEncoding=utf-8&zeroDateTimeBehavior=CONVERT_TO_NULL&serverTimezone=Asia/Shanghai&allowMultiQueries=true
4. username: root
5. password: admin
6. sql-script-encoding: UTF-8

讀取配置信息 DataSourceConfig.java，創建默認的數據源

1. package utry.hikaricp.config;
2. import com.zaxxer.hikari.HikariDataSource;
3. import org.springframework.beans.factory.annotation.Value;
4. import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
5. import org.springframework.context.annotation.Bean;
6. import org.springframework.context.annotation.Configuration;
7. import org.springframework.transaction.annotation.EnableTransactionManagement;
8. import utry.hikaricp.DataSourceProvider;
9. import utry.hikaricp.info.DataSourceInfo;
10. import utry.hikaricp.source.MyHikariDataSource;
11. @Configuration
12. @EnableTransactionManagement
13. publicclassDataSourceConfig{
14. @Value("${spring.datasource.url}")
15. privateString url;
16. @Value("${spring.datasource.username}")
17. privateString userName;
18. @Value("${spring.datasource.password}")
19. privateString password;
20. @Bean
21. @ConditionalOnMissingBean(MyHikariDataSource.class)
22. publicMyHikariDataSource dataSource() {
23. DataSourceInfo info = newDataSourceInfo();
24. info.setUrl(url);
25. info.setUsername(userName);
26. info.setPassword(password);
27. HikariDataSource dataSource = DataSourceProvider.create(info);
28. MyHikariDataSource hikariCPDataSource = newMyHikariDataSource();
29. hikariCPDataSource.updateDataSourceMap("1", dataSource);
30. return hikariCPDataSource;
31. }
32. }

通過 DataSourceProvider 創建 HikariDataSource

1. package utry.hikaricp;
2. import com.zaxxer.hikari.HikariConfig;
3. import com.zaxxer.hikari.HikariDataSource;
4. import utry.hikaricp.info.DataSourceInfo;
5. publicclassDataSourceProvider{
6. publicstaticHikariDataSource create(DataSourceInfo sourceInfo) {
7. HikariConfig hikariConfig = newHikariConfig();
8. hikariConfig.setUsername(sourceInfo.getUsername());
9. hikariConfig.setPassword(sourceInfo.getPassword());
10. hikariConfig.setJdbcUrl(sourceInfo.getUrl());
11. hikariConfig.setDriverClassName("com.mysql.jdbc.Driver");
12. returnnewHikariDataSource(hikariConfig);
13. }
14. }

最核心的數據源的類 MyHikariDataSource.java

1. package utry.hikaricp.source;
2. import com.zaxxer.hikari.HikariDataSource;
3. import org.springframework.jdbc.datasource.AbstractDataSource;
4. import javax.sql.DataSource;
5. import java.io.Closeable;
6. import java.io.IOException;
7. import java.sql.Connection;
8. import java.sql.SQLException;
9. import java.util.HashMap;
10. import java.util.Map;
11. publicclassMyHikariDataSourceextendsAbstractDataSource{
12. privatestaticMap<string> dataSourceMap = newHashMap<>(1);/<string>
13. @Override
14. publicConnection getConnection() throwsSQLException{
15. return dataSourceMap.get("1").getConnection();
16. }
17. @Override
18. publicConnection getConnection(String username, String password) throwsSQLException{
19. return dataSourceMap.get("1").getConnection(username, password);
20. }
21. privatevoid destroy(){
22. DataSource dataSource = dataSourceMap.get("1");
23. Closeable closeable = (Closeable) dataSource;
24. if(closeable != null) {
25. try{
26. closeable.close();
27. } catch(IOException e) {
28. e.printStackTrace();
29. }
30. }
31. }
32. publicvoid updateDataSourceMap(String key, HikariDataSource value) {
33. destroy();
34. dataSourceMap.put(key, value);
35. }
36. }

只要將上面這個類中的 DataSourceMap 集合中的 HikariDataSource 修改就能實現數據源的切換了，調用 updateDataSourceMap() 方法修改即可（修改之前，先關閉之前的數據源，這裡寫死的 map 中 key=1，讀者可以實現動態設置）

實體類 UserInfo.java

1. package utry.hikaricp.model;
2. publicclassUserInfo{
3. privateInteger id;
4. privateString remarks;
5. publicUserInfo() {
6. }
7. publicUserInfo(Integer id, String remarks) {
8. this.id = id;
9. this.remarks = remarks;
10. }
11. publicInteger getId() {
12. return id;
13. }
14. publicvoid setId(Integer id) {
15. this.id = id;
16. }
17. publicString getRemarks() {
18. return remarks;
19. }
20. publicvoid setRemarks(String remarks) {
21. this.remarks = remarks;
22. }
23. }

HikariCpController.java 兩個接口：

1. 更新數據源
2. 查詢用戶信息
3. package utry.hikaricp.controller;
4. import org.springframework.beans.factory.annotation.Autowired;
5. import org.springframework.web.bind.annotation.RequestMapping;
6. import org.springframework.web.bind.annotation.RestController;
7. import utry.hikaricp.factory.HikariCPDataSourceFactory;
8. import utry.hikaricp.mapper.UserInfoMapper;
9. import utry.hikaricp.model.UserInfo;
10. @RestController
11. publicclassHikariCpController{
12. @Autowired
13. privateUserInfoMapper mapper;
14. @Autowired
15. privateHikariCPDataSourceFactory factory;
16. @RequestMapping("update")
17. publicvoid info(String username, String password, String url) {
18. factory.reload(username, password, url);
19. }
20. @RequestMapping("get")
21. publicUserInfoget() {
22. try{
23. UserInfo userInfo = mapper.selectByPrimaryKey(1);
24. return userInfo;
25. } catch(Exception e) {
26. e.printStackTrace();
27. }
28. returnnull;
29. }
30. }

啟動項目

1、調用 get 接口，返回的數據是 test 庫中的

2、調用 update 請求更新數據源

調用成功之後，可以看到，之前的數據源已經被 shutdown，初始化了一個新的數據源

3、再次調用 get 請求，可以看到獲取的 test2 數據庫中的數據

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關鍵字: 數據源 數據庫 庫中