Springboot AOP导致@Autowired注入失败问题

1、使用AOP做日志记录，pom.xml添加依赖。

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

2、新建切面类

package com.study.nms.aop;

import com.alibaba.fastjson.JSON;

import com.alibaba.fastjson.JSONObject;
import com.study.nms.model.security.User;
import com.study.nms.model.system.Log;
import com.study.nms.service.system.LogService;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.AfterReturning;
import org.aspectj.lang.annotation.AfterThrowing;
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 org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.Servlet;
import javax.servlet.ServletContext;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import java.lang.reflect.Method;
import java.text.SimpleDateFormat;
import java.util.Date;

/**
 * 系统日志：切面处理类
 */
@Aspect
@Component
public class SystemLogAspect {


    @Autowired
    private LogService logService;

    //定义切点 @Pointcut
    //在注解的位置切入代码
    @Pointcut("@annotation( com.haige.nms.aop.SystemLogInterface)")
    public void logPoinCut() {
    }

    //切面 配置通知
    @AfterReturning("logPoinCut()")
    public void saveSysLog(JoinPoint joinPoint) {
        //保存日志
        Log saveLog = new Log();

        //从切面织入点处通过反射机制获取织入点处的方法
        MethodSignature signature = (MethodSignature) joinPoint.getSignature();
        //获取切入点所在的方法
        Method method = signature.getMethod();

        //获取操作
        SystemLogInterface myLog = method.getAnnotation(SystemLogInterface.class);
        if (myLog != null) {
            String value = myLog.value();
            saveLog.setOperation(value);//保存获取的操作
            saveLog.setLevel(myLog.level());
        }

        //获取请求的类名
        String className = joinPoint.getTarget().getClass().getName();
        //获取请求的方法名
        String methodName = method.getName();
        saveLog.setMethodName(methodName);

        //请求的参数
        Object[] args = joinPoint.getArgs();
        //将参数所在的数组转换成json
        Object[] arguments  = new Object[args.length];
        for (int i = 0; i < args.length; i++) {//排除不能序列化的参数
            if (args[i] instanceof ServletRequest || args[i] instanceof ServletResponse || args[i] instanceof MultipartFile) {
                continue;
            }
            arguments[i] = args[i];
        }
        String paramter = "";
        if (arguments != null) {
            try {
                paramter = JSONObject.toJSONString(arguments);
            } catch (Exception e) {
                paramter = arguments.toString();
            }
        }
        saveLog.setArgs(paramter);

        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        saveLog.setDate(sdf.format(new Date()));
        //获取用户名
        ServletRequestAttributes requestAttributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
        HttpServletRequest request = requestAttributes.getRequest();
        User user = (User)request.getSession().getAttribute("user");
        if(user != null){
            saveLog.setUsername(user.getUsername());
        }else{
            saveLog.setUsername("未知");
        }
        //获取用户ip地址
        if(request.getRemoteAddr().equals("0:0:0:0:0:0:0:1")){
            saveLog.setHost("localhost");
        }else{
            saveLog.setHost(request.getRemoteAddr());
        }
        saveLog.setUrl(request.getRequestURI());
        //调用service保存SysLog实体类到数据库
        logService.saveLog(saveLog);

    }

    @AfterThrowing("logPoinCut()")
    public void saveThrowingSysLog(JoinPoint joinPoint) {
        System.out.println("切面方法异常");
    }

}

3、新建接口类，实现自定义操作内容及日志级别

import java.lang.annotation.*;

@Target(ElementType.METHOD) //注解放置的目标位置,METHOD是可注解在方法级别上
@Retention(RetentionPolicy.RUNTIME) //注解在哪个阶段执行
@Documented //生成文档
public @interface SystemLogInterface {

    String value() default "";
    String level() default "INFO";
}

4、在Controller类添加注解。

import com.study.nms.aop.SystemLogInterface;
import com.study.nms.model.security.User;
import com.study.nms.service.security.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.support.SessionStatus;

import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.util.Map;

@Controller
public class LoginController {
    @Autowired
    private UserService userService;

    @SystemLogInterface(value = "账号登录",level = "INFO")
    @RequestMapping("/login")
    public String login(@RequestParam(value = "username")String username,
                        @RequestParam(value = "password")String password,
                        Map<String,Object> map,HttpSession session,
                        HttpServletResponse response){

        User user = userService.findUserByUsername(username);
        session.setAttribute("user",user);
        if(user != null){
            if(user.getPassword().equals(password)){
                if(user.isEnabled()){
                    Cookie cookie=new Cookie("username",user.getUsername());
                    cookie.setPath("/");
                    cookie.setMaxAge(30 * 24 * 60 * 60);
                    response.addCookie(cookie);
                    return "redirect:/index.html";
                }else{
                    map.put("msg","该账号已被禁用");
                    return "login";
                }
            }else{
                map.put("msg","用户名密码错误");
                return "login";
            }
        }else{
            map.put("msg","用户名不存在");
            return "login";
        }
    }

}

5、重点！！！！！！！！！！！！！！！！！！！

AOP注解的Controller类方法必须为 public 或 protect ，千万不能用private！！！！！！！！否则会@Autowired注入的service会报空指针异常。