Springboot中自定义注解实现AOP接口开发

1、自定义一个注解

package com.example.demo.wb;


import java.lang.annotation.*;

//自定义注解，名叫WB
@Target({ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
@documented
@Inherited
public @interface WB {

}

2、建一个controller，并在需要aop拦截的方法上添加自定义注解

package com.example.demo.wb;

import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class MyController {

    @WB
    @RequestMapping("/myrequest")
    public String doRequest(){
        return "已处理";
    }
}

3、编写AOP接口，最最最关节的注解是@Aspect

package com.example.demo.wb;

import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.springframework.stereotype.Component;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.servlet.http.HttpServletRequest;

@Aspect
@Component
public class MyAop {

    //切面连接处
    @Pointcut("@annotation(com.example.demo.wb.WB)")
    public void cutMethod(){}

    @Before(value="cutMethod()")
    public void doCut() throws Exception {
        //获取请求属性
        ServletRequestAttributes attributes =
                (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
        //获取请求对象
        HttpServletRequest request = attributes.getRequest();

        //获取请求头中的tt参数
        String string=request.getHeader("tt");
        System.out.println("请求头中的tt参数为："+string);

        if(string==null){
            //如果tt参数为空，抛异常
            //也可做其他操作
            throw new Exception("请求头中的tt参数为空");
        }

    }


}

4、postman测试，发一个请求