jdk动态代理与cglib动态代理简单样例

你的名字 2022-05-27 02:50 98阅读 0赞

***概述:     ***jdk动态代理代理的是接口, 根据具体的实现类动态生成接口的实现类

cglib动态代理代理的是类, 根据具体的实现类生成实现类的子类

*接口与实现类:   *

1.接口:IUserService

package proxy;
    
    /**
     * @author: lybing
     * @create: 2018-04-10-11:24
     * @desc: jdk proxy
     */
    
    public interface IUserService {
    
        /**
         * method test
         */
        void test();
    }

2.实现类UserServiceImpl

package proxy;
    
    /**
     * @author: lybing
     * @create: 2018-04-10-11:25
     * @desc: userService implements
     */
    
    public class UserServiceImpl implements IUserService{
    
        @Override
        public void test() {
            System.out.println("do test...");
        }
    }

***jdk动态代理:***

package proxy;
    
    import java.lang.reflect.InvocationHandler;
    import java.lang.reflect.Method;
    import java.lang.reflect.Proxy;
    
    /**
     * @author: lybing
     * @create: 2018-04-10-11:27
     * @desc: jdk proxy
     */
    
    public class JdkProxyUserService implements InvocationHandler{
    
        private Object target;
    
        public JdkProxyUserService(IUserService target) {
            this.target = target;
        }
    
        public IUserService getProxy(){
            return (IUserService) Proxy.newProxyInstance(JdkProxyUserService.class.getClassLoader(),
                    target.getClass().getInterfaces(), this);
        }
    
        @Override
        public Object invoke(Object o, Method method, Object[] objects) throws Throwable {
            System.out.println("---------BEFORE INVOKE---------");
            // 调用者为具体实例对象
            Object result = method.invoke(target, objects);
            System.out.println("---------AFTER INVOKE---------");
            return result;
        }
    
        public static void main(String[] args) {
            IUserService userService = new UserServiceImpl();
            IUserService proxy = new JdkProxyUserService(userService).getProxy();
            System.out.println(userService.getClass().getName());
            System.out.println(proxy.getClass().getName());
            proxy.test();
        }
    }

***cglib动态代理:***

package proxy;
    
    import org.springframework.cglib.proxy.Enhancer;
    import org.springframework.cglib.proxy.MethodInterceptor;
    import org.springframework.cglib.proxy.MethodProxy;
    
    import java.lang.reflect.Method;
    
    /**
     * @author: lybing
     * @create: 2018-04-10-11:43
     * @desc: cglib proxy
     */
    
    public class CglibProxyUserService implements MethodInterceptor{
    
        private Object target;
    
        public CglibProxyUserService(Object object){
            this.target = object;
        }
    
        public IUserService getProxy(){
            Enhancer enhancer = new Enhancer();
            enhancer.setSuperclass(target.getClass());
            enhancer.setCallback(this);
            return (IUserService)enhancer.create();
        }
    
        @Override
        public Object intercept(Object o, Method method, Object[] objects, MethodProxy methodProxy) throws Throwable {
            System.out.println("=======BEFORE INVOKE======");
            // 调用者为具体实例对象
            Object result = method.invoke(target, objects);
            System.out.println("=======AFTER INVOKE======");
            return result;
        }
    
        public static void main(String[] args) {
            IUserService userService = new UserServiceImpl();
            IUserService proxy = new CglibProxyUserService(userService).getProxy();
            System.out.println(userService.getClass().getName());
            System.out.println(proxy.getClass().getName());
            proxy.test();
        }
    }