Spring/SpringBoot--AOP--获取注解信息

我会带着你远行 2022-09-15 12:27 841阅读 0赞

原文网址：[Spring/SpringBoot--AOP--获取注解信息\_IT利刃出鞘的博客-CSDN博客][Spring_SpringBoot--AOP--_IT_-CSDN]

# 简介 #

**说明**

本文介绍Spring的AOP的用法：自定义注解，在接口上使用此注解，然后在AOP中获得注解的相关信息。

**其他**

因为AOP可以将切点设为注解类，因此，若想控制Controller，只需要控制@RequestMapping，即：

@Pointcut("@annotation(org.springframework.web.bind.annotation.RequestMapping)")

# 创建工程 #

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2ZlaXlpbmcwY2FuZ2xhbmc_size_16_color_FFFFFF_t_70][]

**pom.xml**

<?xml version="1.0" encoding="UTF-8"?>
    <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
        <modelVersion>4.0.0</modelVersion>
        <parent>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-parent</artifactId>
            <version>2.3.1.RELEASE</version>
            <relativePath/> 
        </parent>
        <groupId>com.example</groupId>
        <artifactId>demo_springaop-simple</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <name>demo_springaop-simple</name>
        <description>Demo project for Spring Boot</description>
    
        <properties>
            <java.version>1.8</java.version>
        </properties>
    
        <dependencies>
            <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>
    
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-test</artifactId>
                <scope>test</scope>
                
                
                
                
                
                
            </dependency>
    
            <dependency>
                <groupId>org.projectlombok</groupId>
                <artifactId>lombok</artifactId>
                <version>1.16.20</version>
                <scope>provided</scope>
            </dependency>
    
        </dependencies>
    
        <build>
            <plugins>
                <plugin>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-maven-plugin</artifactId>
                </plugin>
            </plugins>
        </build>
    
    </project>

# 公共代码 #

**注解类**

package com.example.demo.annotation;
    
    import java.lang.annotation.*;
    
    @Target({ElementType.METHOD})
    @Retention(RetentionPolicy.RUNTIME)
    @Documented
    public @interface OperationLog {
        //操作的类型，添加，更新，删除
        String type() default "add";
    
        //操作描述
        String desc() default "";
    }

**Controller**

package com.example.demo.controller;
    
    import com.example.demo.annotation.OperationLog;
    import com.example.demo.entity.User;
    import com.example.demo.service.UserService;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Controller;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.ResponseBody;
    
    @RequestMapping("/user")
    @Controller
    public class UserController {
        @Autowired
        UserService userService;
    
        @RequestMapping("/print")
        @ResponseBody
        public User testPrint(User user) {
            userService.printUser(user);
            return user;
        }
    
        @RequestMapping("/add")
        @ResponseBody
        @OperationLog(type = "添加", desc = "添加数据")
        public User testAdd(User user) {
            return user;
        }
    
        @RequestMapping("/update")
        @ResponseBody
        @OperationLog(type = "更新", desc = "更新数据")
        public User testUpdate(User user) {
            userService.printUser(user);
            return user;
        }
    }

**Entity**

package com.example.demo.entity;
    
    import lombok.Data;
    
    @Data
    public class User {
        private Integer id;
        private String userName;
        private String note;
    }

**Service**

package com.example.demo.service;
    
    import com.example.demo.entity.User;
    
    public interface UserService {
        public void printUser(User user);
    }

package com.example.demo.service.impl;
    
    import com.example.demo.entity.User;
    import com.example.demo.service.UserService;
    import org.springframework.stereotype.Service;
    
    @Service
    public class UserServiceImpl implements UserService {
        @Override
        public void printUser(User user) {
            if (user == null) {
                throw new RuntimeException("检查用户参数是否为空");
            }
            System.out.print("id = " + user.getId());
            System.out.print("\t userName = " + user.getUserName());
            System.out.println("\t note = " + user.getNote());
        }
    }

**启动类**

package com.example.demo;
    
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    
    @SpringBootApplication
    public class DemoSpringaopSimpleApplication {
        public static void main(String[] args) {
            SpringApplication.run(DemoSpringaopSimpleApplication.class, args);
        }
    }

# 单入参有返回值 #

package com.example.demo.aspect;
    
    import com.example.demo.annotation.OperationLog;
    import com.example.demo.entity.User;
    import org.aspectj.lang.ProceedingJoinPoint;
    import org.aspectj.lang.annotation.Around;
    import org.aspectj.lang.annotation.Aspect;
    import org.aspectj.lang.annotation.Pointcut;
    import org.aspectj.lang.reflect.MethodSignature;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Component;
    
    import java.lang.annotation.Annotation;
    import java.lang.reflect.Method;
    import java.text.SimpleDateFormat;
    
    @Aspect
    @Component
    public class OperationLogAspect {
        //切点表达式，表示加了OperationLog注解的都是切点，路径是自定义注解的全路径
        @Pointcut("@annotation(com.example.demo.annotation.OperationLog)")
        public void pointcut() {
    
        }
    
    //    有ProceedingJoinPoint无注解类，有返回值
        @Around("pointcut()")
        public Object around1(ProceedingJoinPoint joinPoint) throws Throwable {
            MethodSignature methodSignature = (MethodSignature) joinPoint.getSignature();
            Method method = methodSignature.getMethod();
            System.out.println("joinPoint.getTarget().toString()  : " + joinPoint.getTarget().toString());
            System.out.println("methodSignature.getName()         : " + methodSignature.getName());
            System.out.println("method.getName()                  : " + method.getName());
            System.out.println("method.getReturnType().getName()  : " + method.getReturnType().getName());
            System.out.println("-----------------------------------------------");
    
            Object object = joinPoint.proceed();
    
            OperationLog operationLog = method.getAnnotation(OperationLog.class);
            System.out.print("type: " + operationLog.type());
            System.out.println("\tdesc: " + operationLog.desc());
            System.out.println("-----------------------------------------------");
    
            Object[] objects = joinPoint.getArgs();
            for (Object o : objects) {
                System.out.println(o);
                if (o instanceof User) {
                    System.out.println("id是：" + ((User)(o)).getId() +
                                        "; 名字是：" + ((User)(o)).getUserName() +
                                        "; 备注是：" + ((User)(o)).getNote());
                }
            }
            return object;
        }
    }

**测试**

postman访问：[http://localhost:8080/user/add?id=321&userName=Tony&note=abc][http_localhost_8080_user_add_id_321_userName_Tony_note_abc]

后端结果

joinPoint.getTarget().toString()  : com.example.demo.controller.UserController@10852612
    methodSignature.getName()         : testAdd
    method.getName()                  : testAdd
    method.getReturnType().getName()  : com.example.demo.entity.User
    -----------------------------------------------
    type: 添加	desc: 添加数据
    -----------------------------------------------
    User(id=321, userName=Tony, note=abc)
    id是：321; 名字是：Tony; 备注是：abc

postman结果

{
        "id": 321,
        "userName": "Tony",
        "note": "abc"
    }

postman访问：[http://localhost:8080/user/update?id=321&userName=Tony&note=abc][http_localhost_8080_user_add_id_321_userName_Tony_note_abc]

后端结果

joinPoint.getTarget().toString()  : com.example.demo.controller.UserController@10852612
    methodSignature.getName()         : testUpdate
    method.getName()                  : testUpdate
    method.getReturnType().getName()  : com.example.demo.entity.User
    -----------------------------------------------
    id = 321	 userName = Tony	 note = abc
    type: 更新	desc: 更新数据
    -----------------------------------------------
    User(id=321, userName=Tony, note=abc)
    id是：321; 名字是：Tony; 备注是：abc

postman结果

{
        "id": 321,
        "userName": "Tony",
        "note": "abc"
    }

# 双参数有返回值 #

package com.example.demo.aspect;
    
    import com.example.demo.annotation.OperationLog;
    import com.example.demo.entity.User;
    import org.aspectj.lang.ProceedingJoinPoint;
    import org.aspectj.lang.annotation.Around;
    import org.aspectj.lang.annotation.Aspect;
    import org.aspectj.lang.annotation.Pointcut;
    import org.aspectj.lang.reflect.MethodSignature;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Component;
    
    import java.lang.annotation.Annotation;
    import java.lang.reflect.Method;
    import java.text.SimpleDateFormat;
    
    @Aspect
    @Component
    public class OperationLogAspect {
        //切点表达式，表示加了OperationLog注解的都是切点，路径是自定义注解的全路径
        @Pointcut("@annotation(com.example.demo.annotation.OperationLog)")
        public void pointcut() {
    
        }
    
    //    有ProceedingJoinPoint和注解类，有返回值
        @Around("@annotation(operationLog)")
        public Object around2(ProceedingJoinPoint joinPoint, OperationLog operationLog) throws Throwable{
            MethodSignature methodSignature = (MethodSignature) joinPoint.getSignature();
            Method method = methodSignature.getMethod();
            System.out.println("joinPoint.getTarget().toString()  : " + joinPoint.getTarget().toString());
            System.out.println("methodSignature.getName()         : " + methodSignature.getName());
            System.out.println("method.getName()                  : " + method.getName());
            System.out.println("method.getReturnType().getName()  : " + method.getReturnType().getName());
            System.out.println("-----------------------------------------------");
    
            Object object = joinPoint.proceed();
    
            System.out.println("method.getName(): " + method.getName());
            System.out.print("type: " + operationLog.type());
            System.out.println("\tdesc: " + operationLog.desc());
            System.out.println("-----------------------------------------------");
    
            Object[] objects = joinPoint.getArgs();
            for (Object o : objects) {
                System.out.println(o);
                if (o instanceof User) {
                    System.out.println("id是：" + ((User)(o)).getId() +
                            "; 名字是：" + ((User)(o)).getUserName() +
                            "; 备注是：" + ((User)(o)).getNote());
                }
            }
            return object;
        }
    }

**测试**

postman访问：[http://localhost:8080/user/add?id=321&userName=Tony&note=abc][http_localhost_8080_user_add_id_321_userName_Tony_note_abc]

后端结果

joinPoint.getTarget().toString()  : com.example.demo.controller.UserController@36efe205
    methodSignature.getName()         : testAdd
    method.getName()                  : testAdd
    method.getReturnType().getName()  : com.example.demo.entity.User
    -----------------------------------------------
    method.getName(): testAdd
    type: 添加	desc: 添加数据
    -----------------------------------------------
    User(id=321, userName=Tony, note=abc)
    id是：321; 名字是：Tony; 备注是：abc

postman结果

{
        "id": 321,
        "userName": "Tony",
        "note": "abc"
    }

postman访问：[http://localhost:8080/user/update?id=321&userName=Tony&note=abc][http_localhost_8080_user_add_id_321_userName_Tony_note_abc]

后端结果

joinPoint.getTarget().toString()  : com.example.demo.controller.UserController@36efe205
    methodSignature.getName()         : testUpdate
    method.getName()                  : testUpdate
    method.getReturnType().getName()  : com.example.demo.entity.User
    -----------------------------------------------
    id = 321	 userName = Tony	 note = abc
    method.getName(): testUpdate
    type: 更新	desc: 更新数据
    -----------------------------------------------
    User(id=321, userName=Tony, note=abc)
    id是：321; 名字是：Tony; 备注是：abc

postman结果

{
        "id": 321,
        "userName": "Tony",
        "note": "abc"
    }

# 单入参无返回值 #

package com.example.demo.aspect;
    
    import com.example.demo.annotation.OperationLog;
    import com.example.demo.entity.User;
    import org.aspectj.lang.ProceedingJoinPoint;
    import org.aspectj.lang.annotation.Around;
    import org.aspectj.lang.annotation.Aspect;
    import org.aspectj.lang.annotation.Pointcut;
    import org.aspectj.lang.reflect.MethodSignature;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Component;
    
    import java.lang.annotation.Annotation;
    import java.lang.reflect.Method;
    import java.text.SimpleDateFormat;
    
    @Aspect
    @Component
    public class OperationLogAspect {
        //切点表达式，表示加了OperationLog注解的都是切点，路径是自定义注解的全路径
        @Pointcut("@annotation(com.example.demo.annotation.OperationLog)")
        public void pointcut() {
    
        }
    
    //    有ProceedingJoinPoint无注解类，无返回值
        @Around("pointcut()")
        public void around3(ProceedingJoinPoint joinPoint) throws Throwable {
            MethodSignature methodSignature = (MethodSignature) joinPoint.getSignature();
            Method method = methodSignature.getMethod();
            System.out.println("joinPoint.getTarget().toString()  : " + joinPoint.getTarget().toString());
            System.out.println("methodSignature.getName()         : " + methodSignature.getName());
            System.out.println("method.getName()                  : " + method.getName());
            System.out.println("method.getReturnType().getName()  : " + method.getReturnType().getName());
            System.out.println("-----------------------------------------------");
    
            Object object = joinPoint.proceed();
    
            OperationLog operationLog = method.getAnnotation(OperationLog.class);
            System.out.print("type: " + operationLog.type());
            System.out.println("\tdesc: " + operationLog.desc());
            System.out.println("-----------------------------------------------");
    
            Object[] objects = joinPoint.getArgs();
            for (Object o : objects) {
                System.out.println(o);
                if (o instanceof User) {
                    System.out.println("id是：" + ((User)(o)).getId() +
                            "; 名字是：" + ((User)(o)).getUserName() +
                            "; 备注是：" + ((User)(o)).getNote());
                }
            }
        }
    }

**测试**

postman访问：[http://localhost:8080/user/add?id=321&userName=Tony&note=abc][http_localhost_8080_user_add_id_321_userName_Tony_note_abc]

后端结果：

joinPoint.getTarget().toString()  : com.example.demo.controller.UserController@71e616a3
    methodSignature.getName()         : testAdd
    method.getName()                  : testAdd
    method.getReturnType().getName()  : com.example.demo.entity.User
    -----------------------------------------------
    type: 添加	desc: 添加数据
    -----------------------------------------------
    User(id=321, userName=Tony, note=abc)
    id是：321; 名字是：Tony; 备注是：abc

postman结果

无

postman访问：[http://localhost:8080/user/update?id=321&userName=Tony&note=abc][http_localhost_8080_user_add_id_321_userName_Tony_note_abc]

后端结果：

joinPoint.getTarget().toString()  : com.example.demo.controller.UserController@71e616a3
    methodSignature.getName()         : testUpdate
    method.getName()                  : testUpdate
    method.getReturnType().getName()  : com.example.demo.entity.User
    -----------------------------------------------
    id = 321	 userName = Tony	 note = abc
    type: 更新	desc: 更新数据
    -----------------------------------------------
    User(id=321, userName=Tony, note=abc)
    id是：321; 名字是：Tony; 备注是：abc

postman结果

无

# 其他网址 #

另见《深入浅出Spring Boot 2.x》=> 4.3 AOP开发详解

[Spring_SpringBoot--AOP--_IT_-CSDN]: https://knife.blog.csdn.net/article/details/120711603
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2ZlaXlpbmcwY2FuZ2xhbmc_size_16_color_FFFFFF_t_70]: /images/20220828/cee4f82db192498c9c39e33b4fe75901.png
[http_localhost_8080_user_add_id_321_userName_Tony_note_abc]: http://localhost:8080/user/add?id=321&userName=Tony&note=abc