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SpringAop 自定义注解 解析

• 1、依赖引入
• 2、新建自定义注解
• 3、新建消息类型枚举
• 4、新建aop切面类解析
• 5、新建controller
• 6、测试方法

1、依赖引入

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>
    
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-aop</artifactId>
</dependency>

2、新建自定义注解

package com.annotation.annotation;

import com.annotation.constant.MessageType;

import java.lang.annotation.*;

/**
 * @author wuzhenyong
 * ClassName:Message.java
 * date:2022-05-23 14:06
 * Description:
 */
@Target({ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface Message {
    /**
     * 消息内容
     */
    public String content() default "";

    /**
     * 发送人
     */
    public String sendUser() default "admin";

    /**
     * 接收人
     */
    public String recvUser() default "admin";

    /**
     * 自定义消息类型
     */
    public MessageType messageType() default MessageType.DEFAULT;
}

3、新建消息类型枚举

package com.annotation.constant;

/**
 * @author wuzhenyong
 * ClassName:MessageType.java
 * date:2022-05-23 14:09
 * Description:
 */
public enum MessageType {
    /**
     * 消息类型
     */
    DEFAULT,
    ONE,
    TWO,
    THREE,

}

4、新建aop切面类解析

package com.annotation.aop;

import com.annotation.annotation.Message;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.Signature;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.stereotype.Component;

import java.lang.reflect.Method;

/**
 * @author wuzhenyong
 * ClassName:MessageAspect.java
 * date:2022-05-23 14:05
 * Description:
 */
@Aspect
@Component
public class MessageAspect {
	/**
     * @annotation(注解类所在路径)
     */
    @Pointcut("@annotation(com.annotation.annotation.Message)")
    public void sendMessagePointCut() {

    }
	
    /**
     * 获取方法上注解
     */
    @Before("sendMessagePointCut()")
    public void sendMessageBefor(JoinPoint joinPoint) {
        MethodSignature methodSignature = (MethodSignature) joinPoint.getSignature();
        Method method = methodSignature.getMethod();
        // 获取注解参数
        Message annotation = method.getAnnotation(Message.class);
        System.out.println("before message ：");
        System.out.println(annotation);
    }

    @After("sendMessagePointCut()")
    public void sendMessageAfter(JoinPoint joinPoint) {

    }

}

5、新建controller

package com.annotation.controller;

import com.annotation.annotation.Message;
import com.annotation.constant.MessageType;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

/**
 * @author wuzhenyong
 * ClassName:MessageController.java
 * date:2022-05-23 14:24
 * Description:
 */
@RestController
@RequestMapping("/message")
public class MessageController {

    @GetMapping("/sendMessage")
    @Message(content = "发送信息", recvUser = "send1", messageType = MessageType.ONE)
    public String sendMessage() {
        return "发送成功";
    }

}

6、测试方法