错误org.springframework.web.HttpMediaTypeNotSupportedException

我在控制器上的rest和方法发布有问题，我有这个2类，第一个是我的类用户，我有我的类，带有getter和setter和默认构造函数，因为最后我想使用Hibernate。：

@Entity
@Table(name="Utilisateur") // mapping with hibernate (but not using in this situation)
public class User {

    @Id
    private long id;
    @Column(name="nom")
    private String nom;
    @Column(name="prenom")
    private String prenom;
    @Column(name="admin")
    private boolean admin;
    @Column(name="actif")
    private boolean actif;
    @Column(name="logins")
    private String logins;
    @Column(name="email")
    private String email;
    @Column(name="naissance")
    private String naissance;
    @Column(name="pwd")
    private String pwd;
    @Column(name="compte")
    private String compte;

    public User(){

    }
    /*
     with getter and setter.
    */
}

和我的类控制器（用户控制器）：主要用于使api成为api。

@RestController
public class UserController {
    @RequestMapping(
        value="/api/greetings/post",
            method = RequestMethod.POST,
            consumes = MediaType.APPLICATION_JSON_VALUE,
            produces=MediaType.APPLICATION_JSON_VALUE
    )
    @ResponseBody
    public ResponseEntity<User> getByEmail(@RequestBody User user){
        if(user==null){

            return new ResponseEntity<User>(HttpStatus.INTERNAL_SERVER_ERROR);
        }
        return new ResponseEntity<User>(user, HttpStatus.OK);
    }

我得到这个错误我正在使用邮递员进行查询，并在我的查询参数中发送此Json查询：

{"id":"3","nom":"Gille","prenom":"Laurent","admin":"1","actif":"0","logins":"gilaur","email":""[email protected],"naissance":"1990/09/09","pwd":"gal","compte":"autre"}

我得到这个错误：

{"timestamp":1457906727481,"status":415,"error":"Unsupported Media Type","exception":"org.springframework.web.HttpMediaTypeNotSupportedException","message":"Content type 'text/plain;charset=UTF-8' not supported","path":"/api/greetings/post/"}

谢谢