springboot 动态多数据源_@switchdatasourcean

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springboot 动态多数据源

 

应用：同一个应用中使用多个数据库，根据需要切换数据库

 

 

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相关类与接口

 

AbstractRoutingDataSource

public abstract class AbstractRoutingDataSource extends AbstractDataSource implements InitializingBean {
 
 
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部分字段
 
    @Nullable
    private Map<Object, Object> targetDataSources;   //目标数据源
 
    @Nullable
    private Object defaultTargetDataSource;         //默认数据源
 
 
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常用方法
 
    public void setTargetDataSources(Map<Object, Object> targetDataSources) {
        this.targetDataSources = targetDataSources;
    }                         //设置目标数据源
 
    public void setDefaultTargetDataSource(Object defaultTargetDataSource) {
        this.defaultTargetDataSource = defaultTargetDataSource;
    }                         //设置默认数据源
 
    @Nullable
    protected abstract Object determineCurrentLookupKey();
                              //抽象方法，设置数据源的key

 

 

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示例：同一应用中向不同的数据库中插入数据

 

数据库h1：表user

数据库h2：表person

 

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config 层

 

DynamicDatasource：动态数据源切换

public class DynamicDataSource extends AbstractRoutingDataSource {
 
    private ThreadLocal<DataSource_Enum> threadLocal=new ThreadLocal<>();
 
    public void switchDataSource(DataSource_Enum dataSource_enum){
        threadLocal.set(dataSource_enum);
    }
 
    @Override
    protected Object determineCurrentLookupKey() {
        return threadLocal.get();
    }

 

DataConfig：配置数据源

@Configuration
@EnableAspectJAutoProxy
@MapperScan("com.example.demo.dao")
public class DataConfig {
 
    @Bean("one")
    @ConfigurationProperties("spring.datasource.druid.one")
    public DataSource initOneDataSource(){
        return DruidDataSourceBuilder.create().build();
    }
 
    @Bean("two")
    @ConfigurationProperties("spring.datasource.druid.two")
    public DataSource initSecondDataSource(){
        return DruidDataSourceBuilder.create().build();
    }
 
    @Bean
    @Primary
    public DynamicDataSource initDynamicDataSource(@Qualifier("one") DataSource ds1, @Qualifier("two") DataSource ds2){
        DynamicDataSource dynamicDataSource=new DynamicDataSource();
 
        Map<Object,Object> map=new HashMap<>();
        map.put(DataSource_Enum.one,ds1);
        map.put(DataSource_Enum.two,ds2);
        dynamicDataSource.setTargetDataSources(map);
 
        dynamicDataSource.setDefaultTargetDataSource(ds1);
 
        return dynamicDataSource;
    }

 

DataSource_Enum

public enum DataSource_Enum{
    one,two
}

 

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aop 层

 

CustomAspect

@Aspect
@Component
public class CustomAspect {
 
    @Resource
    private DynamicDataSource dataSource;
 
    @Pointcut("execution(* *..UserMapper.*(..))")
    public void funOne(){
    }
 
    @Pointcut("execution(* *..PersonMapper.*(..))")
    public void funTwo(){
    }
 
    @Before("funOne()")
    public void beforeOne(){     //使用UserMapper时，使用数据库：one
        dataSource.switchDataSource(DataSource_Enum.one);
    }
 
    @Before("funTwo()")
    public void beforeTwo(){     //使用PersonMapper时，使用数据库：two
        dataSource.switchDataSource(DataSource_Enum.two);
    }
}

 

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controller 层

 

UserController

@RestController
@RequestMapping("/user")
public class UserController {
 
    @Resource
    private UserMapper userMapper;
 
    @RequestMapping("/save")
    public String save(){
        for (int i=0;i<10;i++){
            User user=new User();
            user.setName("瓜田李下 "+i);
            user.setAge(i%5+10);
 
            userMapper.insert(user);
        }
 
        return "success";
    }
}

 

PersonController

@RestController
@RequestMapping("/person")
public class PersonController {
 
    @Resource
    private PersonMapper personMapper;
 
    @RequestMapping("/save")
    public String save(){
        for (int i=0;i<10;i++){
            Person person=new Person();
            person.setName("海贼王 "+i);
            person.setAge(i%4+12);
 
            personMapper.insert(person);
        }
 
        return "success";
    }
}

 

 

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插入数据测试

 

表 user

              

 

表 person