cglib代理与jdk动态代理示例

先看基于jdk实现的动态代理实现例子

1、先声明一个接口类

 public interface UserService{

     public String getName(String msg);
 }

2、实现上面定义的接口类

 public class UserServiceImpl implements UserService {

       @Override
       public String getName(String msg) {
              System.out.println("###enter getName method###");
              return msg;
       }
 }

3、实现InvocationHandler接口类

 import java.lang.reflect.Method;
 import java.lang.reflect.InvocationHandler;

 public class MyInvocationHandler implements InvocationHandler {

       private Object targetObj;

       public MyInvocationHandler(){}

       public MyInvocationHandler(Object obj) {

              this.targetObj = obj;
       }

       @Override
       public Object invoke(Object proxy, Method method, Object[] args)
       throws  Throwable {

                 System.out.println("###enter invoke method pre###");
                 Object result = method.invoke(targetObj, args);
                 System.out.println("###enter invoke method after###");
                 return result;
       }
 }    

4、测试类

 public class JdkProxyMain{

     public static void main(String[] args) {

            UserService service = new UserServiceImpl();
            InvocationHandler invoke = new MyInvocationHandler();

            UserService proxy = (UserService)Proxy.newProxyInstance(service.getClass().getClassLoader(), service.getClass().getInterfaces(), invoke);
            proxy.getName();
     }
 }

Cglib动态代理示例(还是基于上面的接口类及实现接口类,cglib也支持类的实现方式来支持动态代理，需引入cglib jar包)

 public class CglibProxy implements MethodInterceptor {

       @Override
       public Object intercept(Object target, Method method, Object[] params,  MethodProxy methodProxy) throws Throwable {
                System.out.println("....enter invoke pre...");
                methodProxy.invokeSuper(target, params); 
                System.out.println("...enter invoke end...");
               return null;
       }
 }

 public class CglibMain{

     public static void main(String[] args) {
             System.setProperty(DebuggingClassWriter.DEBUG_LOCATION_PROPERTY, "F:\\code");//设置生成代理类的路径
             CglibProxy cglib = new CglibProxy();
             Enhancer enhancer = new Enhancer();
             enhancer.setSuperclass(UserServiceImpl.class);
             enhancer.setCallback(cglib);

             UserService service = (UserService)enhancer.create();
             String result service.getName("cglib");
     }

 }