jdk动态代理与CGLib动态代理

jdk动态代理

目标对象

package com.study;/*** 目标对象（被代理的对象）**/
public class Target implements TargetInf{public String name;public Target() {}public Target(String name) {this.name = name;}public String buyCola (String name){System.out.println("买了一瓶"+name+"可乐");return "给你可乐";}public void byMilk(){System.out.println("买牛奶");}
}

代理对象

package com.study;import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;public class JDKProxyUtil {public static  TargetInf getProxy(Target target){/** ClassLoader loader,Class<?>[] interfaces,InvocationHandler h*/TargetInf o = (TargetInf)Proxy.newProxyInstance(JDKProxyUtil.class.getClassLoader(),new Class[]{TargetInf.class},new InvocationHandler() {@Overridepublic Object invoke(Object proxy, Method method, Object[] args) throws Throwable {System.out.println("before...");Object o1 = method.invoke(target, args);System.out.println("after...");return o1;}});return o;}
}

测试方法

package com.study;import java.lang.reflect.Proxy;/*** jdk动态代理*/
public class Test {public static void main(String[] args) {TargetInf target = (TargetInf) JDKProxyUtil.getProxy(new Target("Tom"));String 百事 = target.buyCola("百事");System.out.println(百事);target.byMilk();}}

jdk动态代理增强的对象必须要实现接口

CGLib动态代理

目标对象可以不实现接口，也可以实现接口

代理对象

package com.study;import net.sf.cglib.proxy.Enhancer;
import net.sf.cglib.proxy.MethodInterceptor;
import net.sf.cglib.proxy.MethodProxy;import java.lang.reflect.Method;public class CGLibProxyUtil {public static  TargetInf getProxy(Target target){Enhancer enhancer = new Enhancer();enhancer.setSuperclass(TargetInf.class);enhancer.setCallback(new MethodInterceptor() {@Overridepublic Object intercept(Object o, Method method, Object[] objects, MethodProxy methodProxy) throws Throwable {System.out.println("CGLIB Before...");Object res = method.invoke(target, objects);System.out.println("CGLIB After...");return res;}});TargetInf o = (TargetInf) enhancer.create();return o;}
}

测试代码

package com.study;import java.lang.reflect.Proxy;/*** jdk动态代理*/
public class Test {public static void main(String[] args) {Target target1 = new Target("Jerry");TargetInf proxy = CGLibProxyUtil.getProxy(target1);String kekou = proxy.buyCola("可口");System.out.println(kekou);proxy.byMilk();}}