动态代理和cglib代理（精简小例子）

1.

@RunWith(AndroidJUnit4.class)
public class ExampleInstrumentedTest {
    final String TAG = "GenericTest";

    //测试通过反射获取到类（class）的方法（method）修饰符（public、private等等）对应的整数值
    @Test(timeout = 100)
    public void testModifierFinalNum() {

        try {
            Log.e(TAG, "try: ");
            Class<?> clazz = Class.forName("com.example.androidstudydemo.ExampleInstrumentedTest");//当前类路径
            Method[] declaredMethods = clazz.getDeclaredMethods();
            for (Method method : declaredMethods) {
                Log.e(TAG, method.getName());
                int modifier = method.getModifiers(); //每个修饰符对应一个整数值，返回的数值是多个修饰符对应数值之和
                Log.e(TAG, method.getName() + "---" + modifier);

                Log.e(TAG, String.valueOf(method.getReturnType().equals(void.class)));
                Log.e(TAG + '1', String.valueOf(method.getReturnType() == int.class));
            }
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
    }
    //fun1()  fun2(),用于验证反射获取其修饰符的值
    private static int fun1() { return 1; }
    public static void fun2() {}

    @Test
    public void testProxy() {
        BuyHouse buyHouse = new BuyHouseImpl();
        BuyHouse proxyBuyHouse = (BuyHouse) Proxy.newProxyInstance(BuyHouse.class.getClassLoader(), new
                Class[]{BuyHouse.class}, new DynamicProxyHandler(buyHouse));
        proxyBuyHouse.buyHosue();
    }

    class DynamicProxyHandler implements InvocationHandler {
        String TAG ="BuyHouseImpl";

        private Object object;

        public DynamicProxyHandler(Object object) {
            this.object = object;
        }

        @Override
        public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
            Log.e(TAG, "买房前");
            Object result = method.invoke(object, args);
            Log.e(TAG, "买房后");
            return (Integer)(result);
        }
    }


    @Test
    public void testCglibProxy(){
//        System.setProperty(DebuggingClassWriter.DEBUG_LOCATION_PROPERTY, "./");
        Enhancer enhancer = new Enhancer();
        enhancer.setSuperclass(BuyBook.class);
        enhancer.setCallback((MethodInterceptor) (obj, method, args, proxy) -> {
            System.out.println("事务开始......" + method.getName());
            Object o1 = proxy.invokeSuper(obj, args);
            System.out.println("事务结束......." + method.getName());
            return o1;
        });
        BuyBook buyBook = (BuyBook) enhancer.create();
        buyBook.buy();
    }

}





interface BuyHouse {
    int buyHosue();
}

class BuyHouseImpl implements BuyHouse {
    String TAG = "BuyHouseImpl";
    @Override
    public int buyHosue() {
        Log.e(TAG, "买房中");
        return 200;
    }
}