jdk 动态代理两种方法实现

不念不忘少年蓝@ 2023-06-12 06:25 22阅读 0赞

方法一: 自己实现invocationHandler

package com.czh.Utils;
    
    import java.lang.reflect.InvocationHandler;
    import java.lang.reflect.Method;
    import java.lang.reflect.Proxy;
    
    public class proxy_class<T> implements InvocationHandler { 
        private  Class<T> target_class;
    
        public proxy_class(Class<T> target_class) { 
            this.target_class = target_class;
        }
    
    
        public Object  newInstance () { 
            return Proxy.newProxyInstance(target_class.getClassLoader(),target_class.getInterfaces(),this);
        }
    
        @Override
        public Object invoke(Object proxy, Method method, Object[] args) throws Throwable { 
            System.out.println("这是动态代理实现类!");
            method.invoke(target_class.newInstance(),args);
            return null;
        }
    
    }

方法二 :

package com.czh.Utils;
    
    import com.czh.domain.impl.userDaoimpl;
    import com.czh.domain.userDao;
    import com.sun.deploy.net.proxy.ProxyHandler;
    import org.junit.Test;
    
    import java.lang.reflect.InvocationHandler;
    import java.lang.reflect.Method;
    import java.lang.reflect.Proxy;
    
    public class jdkpoxy { 
        public static void main(String[] args) { 
            userDao UD = new userDaoimpl();
           /* userDao proxy =(userDao) new Proxy.getInvocationHandler();*/
            /*匿名内部类 实现*/
            userDao proxy = (userDao)Proxy.newProxyInstance(jdkpoxy.class.getClassLoader(),
                  UD.getClass().getInterfaces(),
                  new InvocationHandler() { 
                      @Override
                      public Object invoke(Object proxy, Method method, Object[] args) throws Throwable { 
                          System.out.println("系统执行前:"+System.currentTimeMillis());
                          return method.invoke(UD, args);
                      }
                  });
            proxy.eat("小明!");
            proxy.run();
        }
        /*测试 方法一 实现类*/
        @Test
        public  void  demo2(){ 
            proxy_class<userDaoimpl> userDaoimplproxy_class = new proxy_class<>(userDaoimpl.class);
            userDao o = (userDao)userDaoimplproxy_class.newInstance();
            o.eat("王雪雪");
            o.run();
        }
    
    }