在成功请求 200 中改造空响应

Question

当我尝试登录我的系统时，它 return 一个来自后端的用户对象，它正在 return 使用 http 200:

连接这个 json

{
"data": [1]
  0:{
   "id": 14
   "name": "Adam"
   "email": "email@gmail.com"
   "password": "adam"
   "avatar": ""
   "activity": ""
   "bio": ""
   "member_since": "0000-00-00"
   "remember_token": null
   "created_at": "2016-05-17 17:10:42"
   "updated_at": "2016-05-17 17:10:42"
   }-
   -
}

显然一切正常。但是在 Android studio 中，当我访问 response.body()

时，我获得了一个空对象

我的登录界面方法是这样的：

@GET("users/{name}/{password}")
    Call<UserDTO> login(@Path("name") String name, @Path("password") String password);

这是我得到错误的部分：

Call<UserDTO> call = mRestApi.getService().login(email, password);

        call.enqueue(new Callback<UserDTO>() {
            @Override
            public void onResponse(Call<UserDTO> call, Response<UserDTO> response) {
                //call.cancel();
                if(response.code() == 401) //login incorrecto
                {
                    onLoginFailed();

                }else if(response.code() == 200) {
                    //TODO usuario nulo al venir de una peticion rest

                    Log.d("DEBUG",  response.body().getUser().getName());
                    onLoginSuccess();
                }
            }

            @Override
            public void onFailure(Call<UserDTO> call, Throwable t) {
                call.cancel();
                Toast.makeText(getBaseContext(), "Error de conexión al servidor", Toast.LENGTH_LONG).show();
            }
        });

这一行失败了：

Log.d("DEBUG",  response.body().getUser().getName());

最后Android工作室的错误：

FATAL EXCEPTION: main
Process: myapp.myapp, PID: 3349
java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String myapp.flattomate.Model.User.getName()' on a null object reference

我现在正在使用 DTO 模式，但没有这个我会得到同样的错误。

发生了什么事？

编辑改造 class:

public class restAPI {

    private static final String ENDPOINT = "http://192.168.2.102:8000/";
    private final FlattomateService mService;

    public interface FlattomateService{
        @GET("users/{username}")
        Call<User> getUser(@Path("username") Integer username);

        @GET("users/index")
        Call<List<UserDTO>> allUsers();

        @GET("group/{id}/users")
        Call<List<User>> groupList(@Path("id") int groupId, @Query("sort") String sort);

        @POST("users")
        Call<User> register(@Body User user);

        @GET("users/{name}/{password}")
        Call<UserDTO> login(@Path("name") String name, @Path("password") String password);


    }

    public restAPI(){
        Gson gson = new GsonBuilder()
                .serializeNulls()
                .excludeFieldsWithoutExposeAnnotation()
                .create();

        Retrofit retrofit = new Retrofit.Builder()
                .baseUrl(ENDPOINT)
                .addConverterFactory(GsonConverterFactory.create(gson))
                .build();

        mService = retrofit.create(FlattomateService.class);
    }

    public FlattomateService getService(){ return mService; }


}

UserDTO.java:

public class UserDTO {

    User user;

    public User getUser() { return user; }
}

User.java:

public class User {

    @SerializedName("id")
    @Expose
    private Integer id;
    @SerializedName("name")
    @Expose
    private String name;
    @SerializedName("email")
    @Expose
    private String email;
    @SerializedName("avatar")
    @Expose
    private String avatar;
    @SerializedName("activity")
    @Expose
    private String activity;
    @SerializedName("bio")
    @Expose
    private String bio;
    @SerializedName("member_since")
    @Expose
    private String memberSince;

    @SerializedName("password")
    private String password;

    public User(){}

    public User(String name, String email, String password){
        this.name = name;
        this.email = email;
        this.password = password;

    }
    /**
     *
     * @return
     * The id
     */
    public Integer getId() {
        return id;
    }

    /**
     *
     * @param id
     * The id
     */
    public void setId(Integer id) {
        this.id = id;
    }

    /**
     *
     * @return
     * The name
     */
    public String getName() {
        return name;
    }

    /**
     *
     * @param name
     * The name
     */
    public void setName(String name) {
        this.name = name;
    }

    /**
     *
     * @return
     * The email
     */
    public String getEmail() {
        return email;
    }

    /**
     *
     * @param email
     * The email
     */
    public void setEmail(String email) {
        this.email = email;
    }

    /**
     *
     * @return
     * The avatar
     */
    public String getAvatar() {
        return avatar;
    }

    /**
     *
     * @param avatar
     * The avatar
     */
    public void setAvatar(String avatar) {
        this.avatar = avatar;
    }

    /**
     *
     * @return
     * The activity
     */
    public String getActivity() {
        return activity;
    }

    /**
     *
     * @param activity
     * The activity
     */
    public void setActivity(String activity) {
        this.activity = activity;
    }

    /**
     *
     * @return
     * The bio
     */
    public String getBio() {
        return bio;
    }

    /**
     *
     * @param bio
     * The bio
     */
    public void setBio(String bio) {
        this.bio = bio;
    }

    /**
     *
     * @return
     * The memberSince
     */
    public String getMemberSince() {
        return memberSince;
    }

    /**
     *
     * @param memberSince
     * The member_since
     */
    public void setMemberSince(String memberSince) {
        this.memberSince = memberSince;
    }


}

Answer 1

问题是 json laravel 发送：

$response = Response::make(json_encode(['data'=>$user]), 200)->header('Location', $BASE_URL.$user->id)->header('Content-Type', 'application/json');
    return $response;

Laravel 正在发送改造不知道如何处理的数组。

解决方案就是像这样发送 $user：

$response = Response::make(json_encode($user), 200)->header('Content-Type', 'application/json');

在成功请求 200 中改造空响应

Retrofit null response in a success request 200

rest

android

nullreferenceexception

android-studio

retrofit2