REST简介

• REST，表现形式状态转换

• REST风格描述资源的访问形式

• 按照REST风格来访问资源叫做RESTful

• 按照REST风格访问资源时使用行为动作区分对资源进行了何种操作

  • POST ====>增加
  • DELETE===>删除
  • PUT=====>修改
  • GET=====>查询

RESTful快速开发（标准开发）

• 实体类User

@Data
@AllArgsConstructor
@NoArgsConstructor
public class User {
    private int id;
    private String name;
    private int age;
}

• UserController类

//@Controller
//@ResponseBody
@RestController
@RequestMapping("/users")
public class UserController {

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

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

    @PutMapping
    public String update(@RequestBody User user){
        System.out.println("update  user "+user);
        return "{'module':'update user'}";
    }

    @GetMapping
    public String selectAll(){
        System.out.println("select all users");
        return "{'module':'selectAll users'}";
    }

    @GetMapping("/{id}")
    public String selectById(@PathVariable Integer id){
        System.out.println("select  users"+id);
        return "{'module':'selectById users'}";
    }
}

• 简化开发
  • 使用@RestController代替（@Controller和@ResponseBody）的合体
  • 将@RequestMapping("/users")写在类上面
  • 使用@PostMapping、 @DeleteMapping、@PutMapping、@GetMapping精确请求方式