JDK動態代理的用法是什麼？

使用Proxy和InvocationHandler兩個類，並實現invoke方法

代碼示例如下：

/**
 * @author xuleyan
 * @version MainClass.java, v 0.1 2019-04-08 8:27 PM xuleyan
 */
public class MainClass2 {

    public static void main(String[] args) {

        JdkProxyTest2 jdkProxyTest2 = new JdkProxyTest2();
        Worker worker = (Worker) jdkProxyTest2.bind(new Programmer());
        worker.doWork();

    }
}

/**
 * @author xuleyan
 * @version JdkProxyTest2.java, v 0.1 2020-04-06 10:14 AM xuleyan
 */
public class JdkProxyTest2 implements InvocationHandler {

    /**
     * 真實對象
     */
    private Object target;

    @Override
    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
        System.out.println("do something pre..");
        Object invoke = method.invoke(target, args);
        System.out.println("do something end..");
        return invoke;
    }

    /**
     * 傳入真實對象，返回代理對象
     * @param target
     */
    public Object bind(Object target) {
        this.target = target;
        return Proxy.newProxyInstance(target.getClass().getClassLoader(), target.getClass().getInterfaces(), this);
    }
}

/**
 * @author xuleyan
 * @version Programmer.java, v 0.1 2019-04-08 8:19 PM xuleyan
 */
public class Programmer implements Worker {

    @Override
    public void doWork() {
        System.out.println("寫代碼");
    }
}

/**
 * @author xuleyan
 * @version Worker.java, v 0.1 2019-04-08 8:19 PM xuleyan
 */
public interface Worker {
    void doWork();
}