DataSource Annotation

package com.example.datasource.config;

import java.lang.annotation.*;

@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface DataSource {
    String name() default "";
}

AspectJ Implementation

package com.example.datasource.config;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.*;
import org.springframework.core.Ordered;
import org.springframework.stereotype.Component;

@Aspect
@Component
public class DataSourceInterceptor implements Ordered {

    @Pointcut("@annotation(DataSource)")
    public void dataSourcePointcut() {}

    @Around("dataSourcePointcut()")
    public Object switchDataSource(ProceedingJoinPoint pjp) throws Throwable {
        DataSource annotation = getDataSourceAnnotation(pjp);
        String dsName = annotation != null ? annotation.name() : DataSourceConstants.PRIMARY;
        
        DynamicDataSource.setCurrentDataSource(dsName);
        try {
            return pjp.proceed();
        } finally {
            DynamicDataSource.clearDataSource();
        }
    }

    private DataSource getDataSourceAnnotation(ProceedingJoinPoint pjp) {
        MethodSignature signature = (MethodSignature) pjp.getSignature();
        return signature.getMethod().getAnnotation(DataSource.class);
    }

    @Override
    public int getOrder() {
        return 1;
    }
}

Data Source Constants

package com.example.datasource.config;

public class DataSourceConstants {
    public static final String PRIMARY = "primary";
    public static final String SECONDARY = "secondary";
}

Dynamic Data Source

package com.example.datasource.config;

import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;
import java.util.Map;
import com.alibaba.druid.pool.DruidDataSource;

public class DynamicDataSource extends AbstractRoutingDataSource {
    private static final ThreadLocal<string> currentDataSource = new ThreadLocal<>();

    public DynamicDataSource(DruidDataSource defaultDs, Map<object object=""> targetDataSources) {
        super.setDefaultTargetDataSource(defaultDs);
        super.setTargetDataSources(targetDataSources);
        super.afterPropertiesSet();
    }

    @Override
    protected Object determineCurrentLookupKey() {
        return currentDataSource.get();
    }

    public static void setCurrentDataSource(String dsName) {
        currentDataSource.set(dsName);
    }

    public static void clearDataSource() {
        currentDataSource.remove();
    }
}
</object></string>

Configuration

package com.example.datasource.config;

import com.alibaba.druid.pool.DruidDataSource;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import java.util.HashMap;
import java.util.Map;

@Configuration
public class DataSourceConfig {

    @Bean
    @ConfigurationProperties("spring.datasource.primary")
    public DruidDataSource primaryDataSource() {
        return new DruidDataSource();
    }

    @Bean
    @ConfigurationProperties("spring.datasource.secondary")
    public DruidDataSource secondaryDataSource() {
        return new DruidDataSource();
    }

    @Bean
    @Primary
    public DynamicDataSource routingDataSource(
            DruidDataSource primaryDataSource,
            DruidDataSource secondaryDataSource) {
        
        Map<object object=""> dataSources = new HashMap<>();
        dataSources.put(DataSourceConstants.PRIMARY, primaryDataSource);
        dataSources.put(DataSourceConstants.SECONDARY, secondaryDataSource);
        
        return new DynamicDataSource(primaryDataSource, dataSources);
    }
}
</object>