关于Spring动态代理

Posted 2020-09-18 sunbylm

默认情况下，spring会按照如下规则生成代理：

当类有实现接口，spring会生成JdkDynamicAopProxy代理

当类没有实现接口，spring会生成CglibAopProxy代理

如果想强制spring生成CglibAopProxy代理，可以<aop:config proxy-target-class="true"> </aop:config>

当需要使用CGLIB代理和@AspectJ自动代理支持，请按照如下的方式设置 <aop:aspectj-autoproxy> 的 proxy-target-class 属性：<aop:aspectj-autoproxy proxy-target-class="true"/>

---------------------------------------------------------------------当通过JdkDynamicAopProxy实现代理的时候，如何获取到目标对象-------------------------------------------------------------

private static Object getJdkDynamicProxyTargetObject(Object proxy) throws Exception {
　　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);

　　Object target = ((AdvisedSupport) advised.get(aopProxy)).getTargetSource().getTarget();

　　return target;
}

--------------------------------------------------------------------当通过CglibAopProxy实现代理的时候，如何获取目标对象---------------------------------------------------------------------------

private static Object getCglibProxyTargetObject(Object proxy) throws Exception {
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);

Object target = ((AdvisedSupport) advised.get(dynamicAdvisedInterceptor)).getTargetSource().getTarget();

return target;
}