前后端分离项目 遇到请求跨域问题Access to XMLHttpRequest at......has been blocked by CORS policy: Response to

报错信息：

Access to XMLHttpRequest at 'http://localhost/login' from origin 'http://xxx.xxx.x.x:8080' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: It does not have HTTP ok status.

1.前端–首先Vue发起请求：

axios.post('http://localhost/login',{"userName":this.userName,"password":this.password})
    .then(response=>{
       console.log(response)
     }).catch(error=>{
       this.errorInfo=error;
})

2.后端-- Controller方法接收请求：

/**
     * 管理员登录
     * 由于是前后端分离  使用@RequestBody将json串解析成实体 否则参数无法接收
     * @return
     * @throws Exception
     */
    @RequestMapping("/login")
    public R login(@RequestBody Admin admin)throws Exception{
        Admin u=adminService.login(admin);
        R r=new R();
        if(u==null){
            return R.error("用户名或者密码错误");
        }else{
            String token= JwtUtils.createJWT(String.valueOf(u.getId()),u.getUserName(), SystemConstant.JWT_TTL);
            r.put("token",token);
        }
        return r;
    }

3.解决前后端分离项目 跨域问题 ：增加配置类

import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.CorsRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

/**
    解决跨域问题 配置类
 */
@Configuration
public class WebAppConfigurer implements WebMvcConfigurer {

    @Override
    public void addCorsMappings(CorsRegistry registry) {
        registry.addMapping("/**")
                .allowedOrigins("*")
                .allowCredentials(true)
                .allowedMethods("GET", "HEAD", "POST", "PUT", "DELETE","OPTIONS")
                .maxAge(3600);
    }
}