package com.kuaff.jdk5;

import java.lang.annotation.*;

@Retention(RetentionPolicy.RUNTIME)

@Target(ElementType.METHOD)

public @interface BookAuthor

{

    String name();

       String email();

}

package com.kuaff.jdk5;

import java.lang.annotation.Annotation;

public class MetadataShow

{

    @BookAuthor(name="曹雪芹",email="[email protected]")

    public void introHongLouMeng()

    {

        System.out.println("这是一本好书啊");

    }

    public static void main(String[] args)

    {

        MetadataShow metadata = new MetadataShow();

        try

        {

            Annotation[] annotation = metadata.getClass().getMethod("introHongLouMeng").getAnnotations();

            for(Annotation  a : annotation)

            {

                System.out.printf("作者:%s%n", ((BookAuthor)a).name());

                System.out.printf("他的电子邮件(可能已被注销):%s%n", ((BookAuthor)a).email());

            }

        }

        catch (SecurityException e)

        {

            e.printStackTrace();

        }

        catch (NoSuchMethodException e)

        {

            e.printStackTrace();

        }

    }

}