动态代理

 1 分为jdk自带代理
 2 实现接口 InvocationHandler  ，用反射调用方法
 3 获取代理类：Proxy.newProxyInstance(cls.getClassLoader(),cls.getInterfaces(), new TestProxy(obj));
 4 
 5 实例：
 6 public interface ReadFile {
 7     public void read();
 8 }
 9 
10 public class Boss implements ReadFile {
11     @Override
12     public void read() {
13         System.out.println("I'm reading files.");
14     }
15 }
16 
17 public class Secretary implements InvocationHandler {
18     private Object object;
19     public Secretary(Object object) {
20         this.object = object;
21     }
22     @Override
23     public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
24         System.out.println("I'm secretary.");
25         Object result = method.invoke(object, args);
26         return result;
27     }
28 }
29 
30 public class Main {
31     public static void main(String[] args) {
32         ReadFile boss = new Boss();
33         InvocationHandler handler = new Secretary(boss);
34         ReadFile secretary = (ReadFile) Proxy.newProxyInstance(
35                 boss.getClass().getClassLoader(),
36                 boss.getClass().getInterfaces(),
37                 handler);
38         secretary.read();
39     }
40 }
41 
42 
43 
44 CGLIB具有简单易用，它的运行速度要远远快于JDK的Proxy动态代理：
45 public class CglibProxy implements MethodInterceptor {
46     @Override
47     public Object intercept(Object o, Method method, Object[] args, MethodProxy methodProxy) throws Throwable {
48         System.out.println("++++++before " + methodProxy.getSuperName() + "++++++");
49         System.out.println(method.getName());
50         Object o1 = methodProxy.invokeSuper(o, args);
51         System.out.println("++++++before " + methodProxy.getSuperName() + "++++++");
52         return o1;
53     }
54 }
55 public class Main2 {
56     public static void main(String[] args) {
57         CglibProxy cglibProxy = new CglibProxy();
58  
59         Enhancer enhancer = new Enhancer();
60         enhancer.setSuperclass(UserServiceImpl.class);
61         enhancer.setCallback(cglibProxy);
62  
63         UserService o = (UserService)enhancer.create();
64         o.getName(1);
65         o.getAge(1);
66     }
67 }