#### 動態代理 ``` 1.代理對象,不需要實現接口 2.代理對象的生成,是利用JDK的API,動態的在內存中構建代理對象(需要我們指定創建代理對象/目標對象實現的接口的類型) 3.動態代理也叫做:JDK代理,接口代理 ``` #### 示例: InvocationHandlerImpl ~~~ public class InvocationHandlerImpl implements InvocationHandler { private Object target; public InvocationHandlerImpl(Object target) { this.target = target; } @Override public Object invoke(Object proxy, Method method, Object[] args) throws Throwable { Object result = null; System.out.println("調用開始....."); result = method.invoke(target, args); System.out.println("調用結束....."); return result; } } ~~~ 測試 ~~~ IUserDao userDao = new IUserDaoImpl(); InvocationHandlerImpl invocationHandler = new InvocationHandlerImpl(userDao); ClassLoader loader = userDao.getClass().getClassLoader(); Class<?>[] interfaces = userDao.getClass().getInterfaces(); IUserDao newProxyInstance = (IUserDao) Proxy.newProxyInstance(loader, interfaces, invocationHandler); newProxyInstance.save(); ~~~