/**
 * 業(yè)務(wù)實(shí)現(xiàn)類接口
 */
public interface OrderService {
    //減庫存操作
    void reduceStock();
}

/**
 * 業(yè)務(wù)實(shí)現(xiàn)類
 */
@Slf4j
public class OrderServiceImpl implements OrderService {
    @Override
    public void reduceStock() {
        try {
            log.info("預(yù)減庫存中……");
            Thread.sleep(1000);
        }catch (Exception e){
            e.printStackTrace();
        }
    }
}

/**
 * 代理類
 */
@Slf4j
public class OrderServiceLogProxy extends OrderServiceImpl{
    @Override
    public void reduceStock() {
        log.info("預(yù)減庫存開始……");
        super.reduceStock();
        log.info("預(yù)減庫存結(jié)束……");
    }
}

    /**
     * 測(cè)試?yán)^承方式實(shí)現(xiàn)的靜態(tài)代理
     */
    @Test
    public void testOrderServiceProxy(){
        OrderServiceLogProxy proxy = new OrderServiceLogProxy();
        proxy.reduceStock();
    }

/**
 * 聚合方式實(shí)現(xiàn)靜態(tài)代理：代理類中引入業(yè)務(wù)類
 */
@Slf4j
public class OrderServiceLogProxy2 implements OrderService {
    private OrderServiceImpl orderService;
    public OrderServiceLogProxy2(OrderServiceImpl orderService) {
        this.orderService = orderService;
    }
    @Override
    public void reduceStock() {
        log.info("預(yù)減庫存開始……");
        orderService.reduceStock();
        log.info("預(yù)減庫存結(jié)束……");
    }
}

    /**
     * 測(cè)試聚合方式實(shí)現(xiàn)的靜態(tài)代理
     */
    @Test
    public void testOrderServiceProxy2() {
        OrderServiceImpl orderService = new OrderServiceImpl();
        OrderServiceLogProxy2 proxy2 = new OrderServiceLogProxy2(orderService);
        proxy2.reduceStock();
    }

/**
 * 聚合方式實(shí)現(xiàn)靜態(tài)代理--日志記錄功能疊加改造
 */
@Slf4j
public class OrderServiceLogProxy3 implements OrderService {
    //注意，這里換成了接口
    private OrderService orderService;
    public OrderServiceLogProxy3(OrderService orderService) {
        this.orderService = orderService;
    }
    @Override
    public void reduceStock() {
        log.info("預(yù)減庫存開始……");
        orderService.reduceStock();
        log.info("預(yù)減庫存結(jié)束……");
    }
}

/**
 * 聚合方式實(shí)現(xiàn)靜態(tài)代理--日志記錄功能疊加改造
 */
@Slf4j
public class OrderServicePermissionProxy implements OrderService {
    //注意，這里換成了接口
    private OrderService orderService;
    public OrderServicePermissionProxy(OrderService orderService) {
        this.orderService = orderService;
    }
    @Override
    public void reduceStock() {
        log.info("權(quán)限驗(yàn)證開始……");
        orderService.reduceStock();
        log.info("權(quán)限驗(yàn)證結(jié)束……");
    }
}

    /**
     * 測(cè)試聚合方式實(shí)現(xiàn)的靜態(tài)代理-功能疊加
     */
    @Test
    public void testOrderServiceProxy3() {
        OrderServiceImpl orderService = new OrderServiceImpl();
        OrderServiceLogProxy2 logProxy2 = new OrderServiceLogProxy2(orderService);
        OrderServicePermissionProxy permissionProxy = new OrderServicePermissionProxy(logProxy2);
        permissionProxy.reduceStock();
    }

import lombok.extern.slf4j.Slf4j;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
/**
 * JDK動(dòng)態(tài)代理實(shí)現(xiàn)，必須實(shí)現(xiàn)InvocationHandler接口
 * InvocationHandler可以理解為事務(wù)處理器，所有切面級(jí)別的邏輯都在此完成
 */
@Slf4j
public class DynamicLogProxy implements InvocationHandler {
    //需要代理的對(duì)象類
    private Object target;

    public DynamicLogProxy(Object target) {
        this.target = target;
    }
    /**
     * @param obj    代理對(duì)象
     * @param method 對(duì)象方法
     * @param args   方法參數(shù)
     * @return
     * @throws Throwable
     */
    @Override
    public Object invoke(Object obj, Method method, Object[] args) throws Throwable {
        log.info("這里是日志記錄切面，日志開始……");
        //使用方法的反射
        Object invoke = method.invoke(target, args);
        log.info("這里是日志記錄切面，日志結(jié)束……");
        return invoke;
    }
}

    /**
     * 測(cè)試JDK動(dòng)態(tài)代理實(shí)現(xiàn)的日志代理類
     */
    @Test
    public void testDynamicLogProxy() {
        OrderServiceImpl orderService = new OrderServiceImpl();
        Class<?> clazz = orderService.getClass();
        DynamicLogProxy logProxyHandler = new DynamicLogProxy(orderService);
        //通過Proxy.newProxyInstance(類加載器, 接口s, 事務(wù)處理器Handler) 加載動(dòng)態(tài)代理
        OrderService os = (OrderService) Proxy.newProxyInstance(clazz.getClassLoader(), clazz.getInterfaces(), logProxyHandler);
        os.reduceStock();
    }

import lombok.extern.slf4j.Slf4j;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
/**
 * 基于JDK動(dòng)態(tài)代理實(shí)現(xiàn)的權(quán)限認(rèn)證代理類
 */
@Slf4j
public class DynamicPermissionProxy implements InvocationHandler{
    private Object target;
    public DynamicPermissionProxy(Object target) {
        this.target = target;
    }
    /**
     * @param obj    代理對(duì)象
     * @param method 對(duì)象方法
     * @param args   方法參數(shù)
     * @return
     * @throws Throwable
     */
    @Override
    public Object invoke(Object obj, Method method, Object[] args) throws Throwable {
        log.info("這里是權(quán)限認(rèn)證切面，開始驗(yàn)證……");
        Object invoke = method.invoke(target,args);
        log.info("這里是權(quán)限認(rèn)證切面，結(jié)束驗(yàn)證……");
        return invoke;
    }
}

    /**
     * 測(cè)試JDK動(dòng)態(tài)代理實(shí)現(xiàn)的日志、權(quán)限功能代理類
     */
    @Test
    public void testDynamicLogAndPermissProxy() {
        OrderServiceImpl orderService = new OrderServiceImpl();
        Class<?> clazz = orderService.getClass();
        DynamicLogProxy logProxyHandler = new DynamicLogProxy(orderService);
        OrderService os = (OrderService) Proxy.newProxyInstance(clazz.getClassLoader(), clazz.getInterfaces(), logProxyHandler);
        //注：這里把日志代理類實(shí)例對(duì)象傳入權(quán)限認(rèn)證代理類中
        DynamicPermissionProxy dynamicPermissionProxy = new DynamicPermissionProxy(os);
        OrderService os2 = (OrderService)Proxy.newProxyInstance(os.getClass().getClassLoader(),os.getClass().getInterfaces(),dynamicPermissionProxy);
        os2.reduceStock();
    }

public class HashMapProxyTest {
    public static void main(String[] args) {
        final HashMap<String, Object> hashMap = new HashMap<>();
        Map<String, Object> mapProxy = (Map<String, Object>) Proxy.newProxyInstance(HashMap.class.getClassLoader(), HashMap.class.getInterfaces(), new InvocationHandler() {
            @Override
            public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
                return method.invoke(hashMap, args);
            }
        });
        mapProxy.put("key1", "value1");
        System.out.println(mapProxy);
    }
}

<aop:aspectj-autoproxy proxy-target-class="true"/>

@EnableAspectJAutoProxy(proxyTargetClass = true)

import lombok.extern.slf4j.Slf4j;
import org.springframework.cglib.proxy.Enhancer;
import org.springframework.cglib.proxy.MethodInterceptor;
import org.springframework.cglib.proxy.MethodProxy;
import java.lang.reflect.Method;
/**
 * 基于Cglib方式實(shí)現(xiàn)動(dòng)態(tài)代理-日志功能
 * 它是針對(duì)類實(shí)現(xiàn)代理的，類不用實(shí)現(xiàn)接口，CGlib對(duì)目標(biāo)類產(chǎn)生一個(gè)子類，通過方法攔截技術(shù)攔截所有的方法調(diào)用
 */
@Slf4j
public class DynamicCglibLogProxy implements MethodInterceptor {
    private Enhancer enhancer = new Enhancer();
    public Object getProxyObj(Class clazz) {
        //設(shè)置父類
        enhancer.setSuperclass(clazz);
        enhancer.setCallback(this);
        enhancer.setUseCache(false);
        return enhancer.create();
    }
    /**
     * 攔截所有目標(biāo)類的方法調(diào)用
     *
     * @param o           目標(biāo)對(duì)象
     * @param method      目標(biāo)方法
     * @param args        方法參數(shù)
     * @param methodProxy 代理類實(shí)例
     * @return
     * @throws Throwable
     */
    @Override
    public Object intercept(Object o, Method method, Object[] args, MethodProxy methodProxy) throws Throwable {
        log.info("這里是日志記錄切面，日志開始……");
        //代理類對(duì)象實(shí)例調(diào)用父類方法
        Object result = methodProxy.invokeSuper(o, args);
        log.info("這里是日志記錄切面，日志結(jié)束……");
        return result ;
    }
}

    /**
     * 測(cè)試Cglib實(shí)現(xiàn)的動(dòng)態(tài)代理-日志功能
     */
    @Test
    public void testGclibDynamicLogProxy(){
        DynamicCglibLogProxy dynamicCglibLogProxy = new DynamicCglibLogProxy();
        OrderServiceImpl orderService = (OrderServiceImpl)dynamicCglibLogProxy.getProxyObj(OrderServiceImpl.class);
        orderService.reduceStock();
    }

<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-core</artifactId>
    <version>4.1.0.RELEASE</version>
</dependency>

<dependency>
     <groupId>junit</groupId>
     <artifactId>junit</artifactId>
     <version>4.11</version>
     <scope>test</scope>
</dependency>