public class OrderServiceImpl implements OrderService {
    @Override
    public Map executeFoodOrder(String userName, Map<String,Integer> foodMap) {
        // 日志记录
        System.out.println("开始记录日志...");
        // 权限校验
        System.out.println("开始校验权限...");
        // 核心业务
        System.out.println("执行下单核心业务...");
        // 日志记录
        System.out.println("结束记录日志...");
        return resultMap;
    }
}

// 1. 定义接口
public interface SmsService {
    String send(String message);
}

// 2. 真实实现类
public class SmsServiceImpl implements SmsService {
    @Override
    public String send(String message) {
        System.out.println("send message:" + message);
        return message;
    }
}

// 3. 静态代理类（需要手动编写）
public class SmsProxy implements SmsService {
    private final SmsService smsService;
    
    public SmsProxy(SmsService smsService) {
        this.smsService = smsService;
    }
    
    @Override
    public String send(String message) {
        System.out.println("before method send()");  // 前置增强
        smsService.send(message);                    // 调用目标方法
        System.out.println("after method send()");   // 后置增强
        return null;
    }
}

// 4. 客户端调用
SmsService smsService = new SmsServiceImpl();
SmsProxy proxy = new SmsProxy(smsService);
proxy.send("java");

before method send()
send message:java
after method send()

// 1. 定义InvocationHandler
public class LoggingInvocationHandler implements InvocationHandler {
    private final Object target;  // 持有被代理对象
    
    public LoggingInvocationHandler(Object target) {
        this.target = target;
    }
    
    @Override
    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
        System.out.println("Before " + method.getName());   // 前置增强
        Object result = method.invoke(target, args);       // 调用目标方法（必须调用！）
        System.out.println("After " + method.getName());    // 后置增强
        return result;
    }
}

// 2. 动态创建代理对象
SmsService target = new SmsServiceImpl();
LoggingInvocationHandler handler = new LoggingInvocationHandler(target);
SmsService proxy = (SmsService) Proxy.newProxyInstance(
    target.getClass().getClassLoader(),
    target.getClass().getInterfaces(),
    handler
);
proxy.send("java");

// 1. 定义目标类（无需实现接口）
public class AliSmsService {
    public String send(String message) {
        System.out.println("send message:" + message);
        return message;
    }
}

// 2. 定义MethodInterceptor
public class DebugMethodInterceptor implements MethodInterceptor {
    @Override
    public Object intercept(Object obj, Method method, Object[] args, MethodProxy proxy) throws Throwable {
        System.out.println("before method " + method.getName());   // 前置增强
        Object object = proxy.invokeSuper(obj, args);              // 调用父类方法
        System.out.println("after method " + method.getName());    // 后置增强
        return object;
    }
}

// 3. 通过Enhancer创建代理
Enhancer enhancer = new Enhancer();
enhancer.setSuperclass(AliSmsService.class);
enhancer.setCallback(new DebugMethodInterceptor());
AliSmsService proxy = (AliSmsService) enhancer.create();
proxy.send("java");