控制層方法不加@ResponseBody返回的json的方法：

1、使用@ResponseBody表示直接在response中加入一實體(如Json格式)并直接返回
??? @RequestMapping(value = "/{courseId}",method = RequestMethod.GET)
??? public @ResponseBody Course getCourseInJson(@PathVariable Integer courseId) {
??????? Course course = courseService.getCoursebyId(courseId);
??????? return course;
??? }

2、返回Json格式數(shù)據(jù)方法2：
??? @RequestMapping(value = "/jsonType/{courseId}",method = RequestMethod.GET)
??? public ResponseEntity<Course> getCourseInJson2(@PathVariable Integer courseId) {
??????? Course course = courseService.getCoursebyId(courseId);
??????? return new ResponseEntity<>(course, HttpStatus.OK);
??? }

按著視頻中代碼，不加會直接報錯

控制器類加上@RestController即可，方法上使用@GetMapping、@PostMapping等。