REST风格的表现形式转化

传统风格资源描述形式
- http://localhost/user/getById?id=1
- http://localhost/user/saveUser
REST风格描述形式
- http://localhost/user/1
- http://localhost/user
优点
- 隐藏资源的访问行为，无法通过地址得知对资源是何种操作
- 书写简化
按照REST风格访问资源时使用行为动作区分
- http://localhost/users 查询全部用户信息 GET (查询)
- http://localhost/users 添加用户信息 POST (添加)
- http://localhost/users 修改用户信息 PUT (修改)
- http://localhost/users/1 查询指定用户信息 GET (查询)
- http://localhost/users/1 删除指定用户 DELETE (删除)
步骤
- @RequestMapping的属性
  1. value（默认）: 设置请求访问路径
  2. method：http请求动作，标准动作(GET/POST/PUT/DELETE)
- 设定http请求动作
  1. @RequestMapping(value = "/users",method = RequestMethod.POST)
  2. @GetMapping @PostMapping @PutMapping @DeleteMapping
- 设定请求参数
  1. @RequestMapping(value = "/users/{id}",method = RequestMethod.DELETE)
  2. @GetMapping("/{id}")
  3. @PathVariable 绑定路径参数与形参名
  4. @RequestBody 用于接收JSON数据
  5. @RequestParam 用户接收url地址传参或表单传参
案例

@RestController
@RequestMapping("/users")
public class UserController {
    //@RequestMapping(value = "/users",method = RequestMethod.POST)
    @PostMapping
    public String save(@RequestBody User user){
        System.out.println("user save ..."+ user);
        return "{'module':user save}";
    }

    //@RequestMapping(value = "/users/{id}",method = RequestMethod.DELETE)
    @DeleteMapping("/{id}")
    public String delete(@PathVariable Integer id){
        System.out.println("user delete ..."+ id);
        return "{'module':user delete}";
    }

    //@RequestMapping(value = "/users",method = RequestMethod.PUT)
    @PutMapping
    public String update(@RequestBody User user){
        System.out.println("user update ..."+ user);
        return "{'module':user update}";
    }

    //@RequestMapping(value = "/users/{id}",method = RequestMethod.GET)
    @GetMapping("/{id}")
    public String getById(@PathVariable Integer id){
        System.out.println("user getById ..."+ id);
        return "{'module':user getById}";
    }

    //@RequestMapping(value = "/users",method = RequestMethod.GET)
    @GetMapping
    public String getAll(){
        System.out.println("user getAll ...");
        return "{'module':user getAll}";
    }
}