上海闵行网站_b2b的模式_注册公司多少钱啊_杭州seo搜索引擎优化公司
public class ItemController {@Autowiredprivate ItemService itemService;@PostMappingpublic ResponseEntity<Item> createItem(@RequestBody Item item) {Item newItem = itemService.create(item);return new ResponseEntity<>(newItem, HttpStatus.CREATED);}@GetMapping("/{itemId}")public ResponseEntity<Item> getItemById(@PathVariable Long itemId) {Item item = itemService.findById(itemId);if (item != null) {return new ResponseEntity<>(item, HttpStatus.OK);} else {return new ResponseEntity<>(HttpStatus.NOT_FOUND);}}">