报错如下：
Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Circular view path [jxsr2]: would dispatch back to the current handler URL [/jxsr2] again. Check your ViewResolver setup! (Hint: This may be the result of an unspecified view, due to default view name generation.)] with root cause
解决方法：
加上@ResponseBody
参考链接：
【1】https://blog.csdn.net/weixin_44259720/article/details/103185972
- dispatcherServlet path exception Circular Servletdispatcherservlet path exception circular dispatcherservlet servlet service context exception dispatcherservlet springframework servlet dispatcherservlet 39 name dispatcherservlet servlet bean dispatcherservlet circular dispatcherservlet springmvc web xml dispatcherservlet 39 name with converting typeerror structure circular