关于张孝祥老师的基础加强中动态代理技术的问题 - 黑马程序员技术交流社区

package com.study.day3;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.util.ArrayList;
import java.util.Collection;
public class TestTest {
public static void main(String[] args) throws Exception {
ArrayList target = new ArrayList();
Advise advise = new MyAdvise();
Collection proxy4 = (Collection) getProxy(target,advise);//问题在这里,只能用强转成Collection和List,不能专程ArrayList
System.out.println(proxy4.toString());//注意:从Object继承来的方法,只有toString,hashCode,equals,
System.out.println(proxy4.getClass());//调用时委托给InvocationHandler,其他的方法Proxy自己都有实现.
}
private static Object getProxy(final Object target,final Advise advise) {
Object proxy3 = Proxy.newProxyInstance(
target.getClass().getClassLoader(),
target.getClass().getInterfaces(),
new InvocationHandler(){
@Override
public Object invoke(Object proxy, Method method, Object[] args)
throws Throwable {
advise.before(method);
Object reValue = method.invoke(target, args);
advise.after(method);
return reValue;
}
}
);
return proxy3;
}
}

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