springBoot学习笔记切换数据源

Posted 2022-12-12 拐柒

springBoot学习笔记（六）切换数据源

• 切换数据源
• • 代码实现
  • • 实体bean
    • ProductMapper
    • ProductService
    • ProductController
    • 配置文件
    • MyDataSourceConfiguratioin
    • RoutingDataSource
    • RoutingDataSourceContext
    • DruidConfig
    • RoutingAspect
    • RoutingWith
    • Springboot03DataaccessApplication

切换数据源

代码实现

实体bean

package com.lagou.pojo;

import lombok.Data;

@Data
public class Product 
	private Integer id;
	private String name;
	private double price;

ProductMapper

public interface ProductMapper 
	@Select("select * from product")
	public List<Product> findAllMaster();
	@Select("select * from product")
	public List<Product> findAllSlave();

ProductService

@Service
public class ProductService 
	@Autowired
	ProductMapper productMapper;
	public void findAllM()
		List<Product> allMaster = productMapper.findAllMaster();
		for (Product product : allMaster) 
			System.out.println(product);
		
	
	public void findAllS()
		List<Product> allMaster = productMapper.findAllSlave();
		for (Product product : allMaster) 
			System.out.println(product);
		
	

ProductController

@RestController
public class ProductController 
	@Autowired
	ProductService productService;
	@RequestMapping("findAllM")
	@RoutingWith("master")
	public String findAllProM()
//		RoutingDataSourceContext master = new RoutingDataSourceContext("master");
		productService.findAllM();
		return "master";
	
	@RequestMapping("findAllS")
	@RoutingWith("slave")
	public String findAllProS()
//		RoutingDataSourceContext master = new RoutingDataSourceContext("slave");
		productService.findAllS();
		return "slave";
	

配置文件

# 数据库连接配置
spring.datasource.master.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.master.jdbc-url=jdbc:mysql:///product_master? useUnicode=true&characterEncoding=utf-8&useSSL=true&serverTimezone=UTC
spring.datasource.master.username=root
spring.datasource.master.password=root

spring.datasource.slave.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.slave.jdbc-url=jdbc:mysql:///product_slave?useUnicode=true&characterEncoding=utf-8&useSSL=true&serverTimezone=UTC
spring.datasource.slave.username=root
spring.datasource.slave.password=root

MyDataSourceConfiguratioin

@Configuration
public class MyDataSourceAutoConfiguration 
	Logger logger = LoggerFactory.getLogger(MyDataSourceAutoConfiguration.class);
	//master
	@Bean
	@ConfigurationProperties(prefix = "spring.datasource.master")
	public DataSource masterDataSource()
		logger.info("master ................... dataSource");
		return DataSourceBuilder.create().build();
	
	//slave
	@Bean
	@ConfigurationProperties(prefix = "spring.datasource.slave")
	public DataSource slaveDataSource()
		logger.info("slave ................... dataSource");
		return DataSourceBuilder.create().build();
	

	@Bean
	@Primary
	public DataSource primaryDataSource(
			@Autowired @Qualifier("masterDataSource")DataSource masterDataSource,
			@Autowired @Qualifier("slaveDataSource")DataSource slaveDataSource
	)
		RoutingDataSource routingDataSource = new RoutingDataSource();
		Map<Object, Object> map = new HashMap<>();
		map.put("master",masterDataSource);
		map.put("slave",slaveDataSource);
		routingDataSource.setTargetDataSources(map);
		return routingDataSource;
	

RoutingDataSource

public class RoutingDataSource extends AbstractRoutingDataSource 
	@Override
	protected Object determineCurrentLookupKey() 
		return RoutingDataSourceContext.getDataSourceRoutingKey();
	

RoutingDataSourceContext

public class RoutingDataSourceContext 
	static final ThreadLocal<String> threadLocal=new ThreadLocal<>();
	//指定数据源类型
	public RoutingDataSourceContext(String key) 
		threadLocal.set(key);
	

	public static String getDataSourceRoutingKey()
		String s = threadLocal.get();
		return s==null?"master":s;
	
	public void close()
		threadLocal.remove();
	

DruidConfig

@Configuration
public class DruidConfig 
	@Bean
	@ConfigurationProperties(prefix = "spring.datasource")
	public DataSource dataSource()
		return new DruidDataSource();
	

RoutingAspect

@Aspect
@Component
public class RoutingAspect 
	@Around("@annotation(routingWith)")
	public Object routingDataSource(ProceedingJoinPoint joinPoint,RoutingWith routingWith) throws Throwable 
		String value = routingWith.value();
		RoutingDataSourceContext master = new RoutingDataSourceContext(value);
		return joinPoint.proceed();
	

RoutingWith

@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
public @interface RoutingWith 
	String value() default "master";

Springboot03DataaccessApplication

@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)
@MapperScan("com.lagou.mapper")
public class Springboot03DataaccessApplication 

	public static void main(String[] args) 
		SpringApplication.run(Springboot03DataaccessApplication.class, args);