注解

注解模拟的Test方法

package com.ail.annotation;

import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;

/**
* 自定义注解
* @author why
*
*/
//把编译时间放入到运行时间

@Retention(RetentionPolicy.RUNTIME)
public @interface Mytt {

}

package com.ail.annotation;

public class Mytest {

@Mytt
public void ren() {

    System.out.println("wode zhujie");
}

@Mytt
public void ren1() {

    System.out.println("wode zhujie2");
}

public void ren2() {

    System.out.println("wode zhujie3");
}

}

package com.ail.annotation;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

public class MyAnnotation {

    public static void main(String[] args) throws ClassNotFoundException, IllegalArgumentException, IllegalAccessException, InvocationTargetException, InstantiationException {

        //模拟test 方法
        //获得类的Class 对象

        Class c = Class.forName("com.ail.annotation.Mytest");

        //获得类的全部方法
         Method[] m = c.getMethods();
         //遍历
         for (Method mm : m) {
             //查找时不是有我自己定义的注解
             boolean b = mm.isAnnotationPresent(Mytt.class);
             if(b==true) {
                 //通过反射执行方法

                 mm.invoke(c.newInstance(), null);

             }


        }

    }

}