现状：在项目中，可能前后端需要分开写，这时将会出现拒绝访问情况 解决方案：在后端方法定义接收头文件即可（亲测有效） 在方法内部加入这三行代码，既可以解决前后端跨域问题
response.addHeader("Access-Control-Allow-Origin", "*"); response.addHeader("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE, OPTIONS"); response.addHeader("Access-Control-Allow-Headers", "Content-Type,X-Requested-With,accept,Origin,Access-Control-Request-Method,Access-Control-Request-Headers,token")一下时项目中，具体实现方法
@ResponseBody @RequestMapping(value = "/findAll") public String FindAll(HttpServletResponse response) { System.out.println("进入 /image_face/findAll 方法"); response.addHeader("Access-Control-Allow-Origin", "*"); response.addHeader("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE, OPTIONS"); response.addHeader("Access-Control-Allow-Headers", "Content-Type,X-Requested-With,accept,Origin,Access-Control-Request-Method,Access-Control-Request-Headers,token") return ""; }