package com.lyms.etl.util;

import org.springframework.aop.framework.AdvisedSupport;
import org.springframework.aop.framework.AopProxy;
import org.springframework.aop.support.AopUtils;

import java.lang.reflect.Field;

/**
 * spring自动注入的对象 通过getClass()获取到的是proxy对象
 * 通过此类获取到真实对象
 * @Author: litao
 * @Date: 2017/5/6 0006 11:21
 * @Version: V1.0
 */
public class AopTargetUtil {
    /**
     * 获取 目标对象
     * @param proxy 代理对象
     * @return
     * @throws Exception
     */
    public static Object getTarget(Object proxy) {
        if(!AopUtils.isAopProxy(proxy)) {
            return proxy;//不是代理对象
        }

        if(AopUtils.isJdkDynamicProxy(proxy)) {
            return getJdkDynamicProxyTargetObject(proxy);
        } else { //cglib
            return getCglibProxyTargetObject(proxy);
        }
    }


    private static Object getCglibProxyTargetObject(Object proxy) {
        Object target = null;
        try {
            Field h = proxy.getClass().getDeclaredField("CGLIB$CALLBACK_0");
            h.setAccessible(true);
            Object dynamicAdvisedInterceptor = h.get(proxy);

            Field advised = dynamicAdvisedInterceptor.getClass().getDeclaredField("advised");
            advised.setAccessible(true);

            target = ((AdvisedSupport)advised.get(dynamicAdvisedInterceptor)).getTargetSource().getTarget();
        } catch (Exception e) {

        }
        return target;
    }


    private static Object getJdkDynamicProxyTargetObject(Object proxy) {
       Object target = null;
       try {
           Field h = proxy.getClass().getSuperclass().getDeclaredField("h");
           h.setAccessible(true);
           AopProxy aopProxy = (AopProxy) h.get(proxy);
           Field advised = aopProxy.getClass().getDeclaredField("advised");
           advised.setAccessible(true);
           target = ((AdvisedSupport)advised.get(aopProxy)).getTargetSource().getTarget();
       } catch (Exception e) {
       }
       return target;
    }

}