通过自定义注解,可以轻松在方法或者类执行时去前置执行各种想要的方法

先导入pom坐标

 <!-- AOP依赖模块 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-aop</artifactId>
        </dependency>
<!-- web依赖相关 -->
 <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

1.先定义自定义注解

@Target({ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
public @interface LogAnnotation {
    String module() default "";

}

2.准备完整服务链 controller层,service层

@RestController
public class HelloWorldController {

   @Autowired
    private SysLogService helloWorldService;

    @LogAnnotation
    @RequestMapping(value = "/info3", method = RequestMethod.GET)
    public void hello() {
      System.out.println("进入controll层");
        helloWorldService.save();
        System.out.println("controller层save方法执行完毕...");
    }

}

@Service
public class SysLogServiceImpl implements SysLogService {
//中间接口就不贴上来了
   

    @Override
    public void save() {
        System.out.println("执行了impl_save方法");
    }

    @Override
    public void myInterface() {
        System.out.println("执行了impl_myInterface方法");
    }




}

3.定义切面

@Aspect
@Component
public class LogAdvice {

    @Autowired
    private SysLogService sysLogService;

    @Around(value = "@annotation(LogAnnotation)")
    public Object logSave(ProceedingJoinPoint joinPoint) throws Throwable {
       

 System.out.println("进入到切点处理方法");
        MethodSignature methodSignature = (MethodSignature) joinPoint.getSignature();
        System.out.println("切点执行1");
        LogAnnotation logAnnotation = methodSignature.getMethod().getDeclaredAnnotation(LogAnnotation.class);
        System.out.println("切点执行2");
            Object object = joinPoint.proceed();
            System.out.println("切点执行3");
            sysLogService.myInterface();
            System.out.println("切点执行4");


}
}

例如设置端口是8099的话,启动访问
http://localhost:8089/info3
得到如下结果

image.png

后续待补充,感觉这个是比较简单的实例了