SpringBoot+自定义注解+AOP高级玩法打造通用开关

1.项目结构
在这里插入图片描述
2.引入依赖

    <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-data-redis</artifactId></dependency></dependencies>

3.yml配置

server:port: 8080
spring:redis:database: 0host: x.x.x.xport: 6379password: 123456jedis:pool:max-active: 10max-wait: -1msmax-idle: 5min-idle: 1

4.自定义注解

package com.example.springbootaop.annotation;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/*** 通用开关注解* @author shixc* 2023/10/17*/
@Target({ElementType.METHOD})  // 作用在方法上
@Retention(RetentionPolicy.RUNTIME)  // 运行时起作用
public @interface ServiceSwitch {/*** 业务开关的key（不同key代表不同功效的开关）* {@link Constant.ConfigCode}*/String switchKey();// 开关，0:关(拒绝服务并给出提示)，1:开(放行)String switchVal() default "0";// 提示信息，默认值可在使用注解时自行定义。String message() default "当前请求人数过多，请稍后重试。";
}

5.定义常量

package com.example.springbootaop.constant;
/*** 常量* @author shixc* 2023/10/17*/
public class Constant {// .... 其他业务相关的常量 ....// 配置相关的常量public static class ConfigCode {// 挂号支付开关(0:关，1:开)public static final String REG_PAY_SWITCH = "reg_pay_switch";// 其他业务相关的配置常量// ....}
}

6.AOP核心实现

package com.example.springbootaop.aop;
import com.example.springbootaop.annotation.ServiceSwitch;
import com.example.springbootaop.constant.Constant;
import com.example.springbootaop.util.Result;
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.data.redis.core.StringRedisTemplate;
import org.springframework.http.HttpStatus;
import org.springframework.stereotype.Component;
import java.lang.reflect.Method;
/*** AOP核心实现* @author shixc* 2023/10/17*/
@Aspect
@Component
public class ServiceSwitchAOP {private final StringRedisTemplate redisTemplate;public ServiceSwitchAOP(StringRedisTemplate redisTemplate) {this.redisTemplate = redisTemplate;}/*** 定义切点，使用了@ServiceSwitch注解的类或方法都拦截*/@Pointcut("@annotation(com.example.springbootaop.annotation.ServiceSwitch)")public void pointcut() {}@Around("pointcut()")public Object around(ProceedingJoinPoint point) {// 获取被代理的方法的参数Object[] args = point.getArgs();// 获取被代理的对象Object target = point.getTarget();// 获取通知签名MethodSignature signature = (MethodSignature) point.getSignature();try {// 获取被代理的方法Method method = target.getClass().getMethod(signature.getName(), signature.getParameterTypes());// 获取方法上的注解ServiceSwitch annotation = method.getAnnotation(ServiceSwitch.class);// 核心业务逻辑if (annotation != null) {String switchKey = annotation.switchKey();String switchVal = annotation.switchVal();String message = annotation.message();/*获取配置项说明这里有两种方式：1、配置加在Redis，查询时从Redis获取；2、配置加在数据库，查询时从表获取。(MySQL单表查询其实很快，配置表其实也没多少数据)我在工作中的做法：直接放到数据库，但是获取配置项的方法用SpringCache缓存，然后在后台管理中操作配置项，变更时清理缓存即可。我这么做就是结合了上面两种各自的优点，因为项目中配置一般都是用后台管理来操作的，查表当然更舒适，同时加上缓存提高查询性能。*/// 下面这块查询配置项，大家可以自行接入并修改。// 数据库这么查询：String configVal = systemConfigService.getConfigByKey(switchKey);// 这里我直接从redis中取，使用中大家可以按照意愿自行修改。String configVal = redisTemplate.opsForValue().get(Constant.ConfigCode.REG_PAY_SWITCH);if (switchVal.equals(configVal)) {// 开关打开，则返回提示。return Result.fail(HttpStatus.FORBIDDEN.value()+"", message);}}// 放行return point.proceed(args);} catch (Throwable e) {throw new RuntimeException(e.getMessage(), e);}}
}

7.使用注解

package com.example.springbootaop.service;
import com.example.springbootaop.annotation.ServiceSwitch;
import com.example.springbootaop.constant.Constant;
import com.example.springbootaop.util.Result;
import org.springframework.http.HttpStatus;
import org.springframework.stereotype.Service;
/*** @author shixc* 2023/10/17*/
@Service
public class RegService {/*** 挂号下单*/@ServiceSwitch(switchKey = Constant.ConfigCode.REG_PAY_SWITCH)public Result createOrder() {// 具体下单业务逻辑省略....return Result.succeed("挂号下单成功");}
}

8.工具类

import java.io.Serializable;
/*** @author shixc* 2023/10/17*/
public final class Result<T> implements Serializable {private static final long serialVersionUID = -8780880627029425781L;private String code;private long timestamp = System.currentTimeMillis();private String message;private T data;public Result() {}private Result(String code, String message, T data) {this.code = code;this.message = message;this.data = data;}public String getCode() {return this.code;}public long getTimestamp() {return this.timestamp;}public String getMessage() {return this.message;}public T getData() {return this.data;}public static <T> Result<T> succeed() {return new Result("0", "", (Object) null);}public static <T> Result<T> succeed(T data) {return new Result("0", "", data);}public static <T> Result<T> panic() {return new Result("000000", "系统运行发生异常，请联系IT处理", (Object) null);}public static <T> Result<T> illegalArgument(String message) {return new Result("000001", message, (Object) null);}public static <T> Result<T> fail(String code, String message) {return new Result(code, message, (Object) null);}public static <T> Result<T> fail(String code, String message, T data) {return new Result(code, message, data);}public boolean success() {return this.code.equals("0");}public boolean failure() {return !this.success();}
}

9.测试接口

package com.example.springbootaop.controller;
import com.example.springbootaop.service.RegService;
import com.example.springbootaop.util.Result;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
/*** 挂号Controller* @author shixc* 2023/10/17*/
@RestController
@RequestMapping("reg")
public class RegController {private final RegService regService;public RegController(RegService regService) {this.regService = regService;}@GetMapping("/create")public Result createOrder() {return regService.createOrder();}
}