public interface Performer {
    void play(String subject);
    String introduction();
}
public interface Director {
    List<String> getCreations();
}
public class DefaultActor implements Performer {
    @Override
    public void play(String subject) {
        System.out.println("[DefaultActor]: 默認(rèn)男演員正在即興表演《" + subject + "》");
    }
    @Override
    public String introduction() {
        return "李白·上李邕： 大鵬一日同風(fēng)起，扶搖直上九萬(wàn)里。假令風(fēng)歇時(shí)下來(lái)，猶能顛卻滄溟水。世人見(jiàn)我恒殊調(diào)，聞?dòng)啻笱越岳湫?。宣父尚能畏后生，丈夫未可輕年少。";
    }
}
public class DefaultDirector implements Director {
    @Override
    public List<String> getCreations() {
        List<String> creations = new ArrayList<>();
        creations.add("《霸王別姬》");
        creations.add("《活著》");
        return creations;
    }
}

package guzb.diy.proxy;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
public class ProxyForInterceptor implements InvocationHandler {
    private Object target;
    public ProxyForInterceptor(Object target) {
        this.target = target;
    }
    @Override
    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
        System.out.println("前置攔截邏輯：開(kāi)始執(zhí)行 " + method.getName() + " 方法");
        Object result = method.invoke(target, args);
        System.out.println("后置攔截邏輯：完成執(zhí)行 " + method.getName() + " 方法");
        return result;
    }
}

public class IntercepterTestMain {
    public static void main(String[] args) {
        // 創(chuàng)建原始對(duì)象
        Performer actor = new DefaultActor();
        Director director = new DefaultDirector();
        // 創(chuàng)建代理對(duì)象
        Performer actorProxy = (Performer) Proxy.newProxyInstance(
                Performer.class.getClassLoader(),
                new Class[]{Performer.class},
                new ProxyForInterceptor(actor)
        );
        Director directorProxy = (Director) Proxy.newProxyInstance(
                Director.class.getClassLoader(),
                new Class[]{Director.class},
                new ProxyForInterceptor(director)
        );
        // 通過(guò)代理對(duì)象調(diào)用方法
        actorProxy.play("京劇");
        System.out.println(actorProxy.introduction());
        System.out.println("導(dǎo)演的作品集：");
        directorProxy.getCreations().forEach(System.out::println);
    }
}

public interface UserMapper {
    @Select("SELECT * FROM user WHERE name = #{name}")
    User findUserByName(String name);
}
// User的POJO類(lèi)
class User {
    private Integer id;
    private String name;
    // getters and setters
}

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
public class MyBatisInvocationHandler implements InvocationHandler {
    @Override
    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
        // 這里假設(shè)能夠獲取到注解并解析它
        // 實(shí)際上，你需要一個(gè)SQL執(zhí)行器來(lái)執(zhí)行這里定義的SQL
        System.out.println("Executing method: " + method.getName());
        System.out.println("Parameters: " + Arrays.toString(args));
        // 模擬的SQL執(zhí)行結(jié)果
        User user = new User();
        user.setId(1);
        user.setName((String) args[0]);
        return user;
    }
}

import java.lang.reflect.Proxy;
public class MyBatisProxyDemo {
    public static void main(String[] args) {
        MyBatisInvocationHandler handler = new MyBatisInvocationHandler();
        UserMapper mapper = (UserMapper) Proxy.newProxyInstance(
            UserMapper.class.getClassLoader(),
            new Class[]{UserMapper.class},
            handler
        );
        User user = mapper.findUserByName("Alice");
        System.out.println("Found user: " + user.getName());
    }
}