动态代理的两种实现方式

JDK的动态代理

必须满足条件：
实现动态代理类和核心类满足实现同一个接口

    public void t2(){
        InvocationHandler invocationHandler = new InvocationHandler() {
            @Override
            public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
                System.out.println(method.getName());
                System.out.println(args.length);
                return null;
            }
        };
        ApplicationContext applicationContext  = new ClassPathXmlApplicationContext("applicationContext.xml");
        UserService userservice = applicationContext.getBean("userservice", UserService.class);
        UserService o = (UserService) Proxy.newProxyInstance(App.class.getClassLoader(), userservice.getClass().getInterfaces(), invocationHandler);
        <!-- 三个参数 
        1、当前类的类加载器
        2、实现动态代理的所有接口
        3、InvocationHanlder 匿名内部类-->
        User queryOne = o.findQueryOne(22);
        System.out.println(queryOne);
    }
}

cglib动态代理

//目标
final UserService us = new UserServiceImpl();
//额外功能
MethodInterceptor mi = new MethodInterceptor(){
    @Override
    public Object intercept(Object o, Method method, Object[] objects, MethodProxy methodProxy) 
        throws Throwable {
        System.out.println("###   before invocation");
        Object result = method.invoke(us, objects);
        System.out.println("###   end invocation");
        return result;
    }
}

Enhancer enhancer = new Enhancer();
// 设置需要代理的对象
enhancer.setSuperclass(us.getClass());
// 设置代理人
enhancer.setCallback(mi);
UserServiceImpl proxy = (UserServiceImpl)enhancer.create();