package com.espread.common.aspect;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;

import com.espread.common.annotation.DataSourceChange;
import com.espread.common.datasource.DynamicDataSource;
import com.espread.common.exception.DataSourceAspectException;

/**
 * 动态数据源切换
 * @author itdragons 2016-9-20 15:47:33
 * {@link com.espread.common.annotation.DataSourceChange} -> 注解方法
 */
@Aspect
@Component
public class DataSourceAspect {
    private static final Logger LOGGER = LoggerFactory.getLogger(DataSourceAspect.class);
    
    @Around("@annotation(dataSourceChange)")
    public Object doAround(ProceedingJoinPoint pjp, DataSourceChange dataSourceChange) {
        Object retVal = null;
        boolean selectedDataSource = false;
        try {
        	selectedDataSource = true;
        	DynamicDataSource.setDataSource(dataSourceChange.value());
            retVal = pjp.proceed();
        } catch (Throwable e) {
            LOGGER.warn("数据源切换错误", e);
            throw new DataSourceAspectException("数据源切换错误", e);
        } finally {
        	if (selectedDataSource) {
        		//重置数据源
                DynamicDataSource.resetDataSource();
            }
        }
        return retVal;
    }
}