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");
    }

}