Develop Reference

Why I am getting JsonSyntaxException Error

I am new to retrofit (I was using volley before), before this I was doing fine with retrofit until this error comes :-
com.google.gson.JsonSyntaxException: java.lang.IllegalStateException:
Expected int but was Boolean at line 8 column 37 path
$.response.data.book_service_id
I tried with every solution provided in this site but could not help myself since I am new to retrofit.
I think it's because of the JSON parsing error. I don't know how to handle it.
This may be a duplicate question but please help.
Below is my code:
Request and fetching data:
private void makeBookingRequest(String position) {
final CustomProgressDialog dialog = new CustomProgressDialog();
dialog.show(getSupportFragmentManager(),"tag");
SharedPreferences preferences = getSharedPreferences("MYSharedPref",MODE_PRIVATE);
String sessionkey = preferences.getString("sessionkey",null);
System.out.println(sessionkey);
String serviceId = position;
System.out.println(position);
APIEndPoints endPoints = Url.getInstance().create(APIEndPoints.class);
Call<Book> call = endPoints.makeBookingRequest(serviceId,sessionkey);
call.enqueue(new Callback<Book>() {
#Override
public void onResponse(Call<Book> call, retrofit2.Response<Book> response) {
dialog.dismiss();
if (!response.isSuccessful()) {
Toast.makeText(HomeActivity.this, "server is not responding", Toast.LENGTH_SHORT).show();
}
else if(response.body() != null){
Book bookData = response.body();
String message = bookData.response.message;
Toast.makeText(HomeActivity.this, message, Toast.LENGTH_SHORT).show();
}
}
#Override
public void onFailure(Call<Book> call, Throwable t) {
dialog.dismiss();
Toast.makeText(HomeActivity.this, "Error" + t.getLocalizedMessage(),
Toast.LENGTH_SHORT).show();
System.out.println(t);
}
});
}
Model Class:
package com.medpal.medpal_client.Models;
import com.google.gson.annotations.SerializedName;
public class Book {
#SerializedName("response")
public ResponseEntity response;
public class ResponseEntity{
#SerializedName("data")
public DataEntity data;
#SerializedName("secondary_message")
public String secondary_message;
#SerializedName("message")
public String message;
#SerializedName("code")
public int code;
}
public class DataEntity {
#SerializedName("book_service_id")
public int book_service_id;
}
}
APIENDPOINTS
#FormUrlEncoded
#Headers({"apikey: testapikey", "Content-Type:application/x-www-form-urlencoded" })
#POST("service/accept?")
Call<Book> makeBookingRequest(
#Field("service_id") String ServiceId,
#Field("session_key") String sessionKey);
URL class
public class Url {
public static final String base_url = "http://www.medpal.net/api/v1/";
public static final String serviceUrl = "http://www.medpal.net/api/v1/services?";
public static Retrofit retrofit;
public static Retrofit getInstance() {
if (retrofit == null) {
retrofit = new Retrofit.Builder()
.baseUrl(base_url)
.addConverterFactory(GsonConverterFactory.create())
.build();
}
return retrofit;
}
}
Finallyy Response from server:
{
"response": {
"error": [],
"code": 200,
"message": "Service booked",
"secondary_message": "Service booked successfully",
"data": {
"book_service_id": 35
}
}
}

To detect the problem exactly, You need to use an interceptor to log the server response, to log the server responses you can use OkHttp3 here is an example of it.
private OkHttpClient provideOkhttpClient() {
OkHttpClient.Builder client = new OkHttpClient.Builder();
client.readTimeout(15000, TimeUnit.MILLISECONDS);
client.writeTimeout(70000, TimeUnit.MILLISECONDS);
HttpLoggingInterceptor interceptor = new HttpLoggingInterceptor();
interceptor.setLevel(HttpLoggingInterceptor.Level.BODY);
client.addInterceptor(interceptor);
return client.build();
}
And add this to your Retrofit.Builder
.client(provideOkhttpClient())
And these are for Gradle
implementation 'com.squareup.okhttp3:okhttp:3.12.0'
implementation 'com.squareup.okhttp3:logging-interceptor:3.5.0'
If you do this you will see everything you sent and got from the server at your Logcat.

retrofit header not change immediately

In my app I have a spinner that includes some language abbreviation example (en, az, and others), I want to set selected language abbreviation as the request header and I need this in every request so I am saving abbreviation in shared preferences and get abbreviation in my ApiClient class,
every time that spinner selection has changed I change shared preferences abbreviation value but header only set the first time I select a language and when I change spinner selection header not change
This is my ApiClient class
private static final String BASE_URL = ApiUrls.server_url;
public static Retrofit getClient(Context context)
{
SharedPrefUtil sharedPrefUtil = new SharedPrefUtil(context);
String locale = sharedPrefUtil.getSelectedLanguage();
OkHttpClient.Builder httpClient = new OkHttpClient.Builder();
httpClient = httpClient.addInterceptor(new Interceptor() {
#Override
public Response intercept(Chain chain) throws IOException
{
Request request = chain.request().newBuilder().header("Accept-Language",
locale).build();
return chain.proceed(request);
}
});
Retrofit retrofit = new Retrofit.Builder().baseUrl(BASE_URL)
.addConverterFactory(GsonConverterFactory.create()).client(httpClient.build())
.build();
return retrofit;
}
This is my ApiRequester class method for sending a request to server
public static void sendLogin(final Context context, Map<String, String> params,
final HttpResponses.onLoginSuccess onLoginSuccess) {
DialogHelper.ProgressDialog progressDialog = showWaitDialog(context);
if (hasInternetConnection(context)) {
params.put("grant_type", "password");
params.put("client_id", "raymon-client");
params.put("client_secret", "raymon-secret");
ApiInterface apiService = ApiClient.getClient(context).create(ApiInterface.class);
Call<ResponseBody> call = apiService.loginRequest(params);
call.enqueue(new Callback<ResponseBody>() {
#Override
public void onResponse(Call<ResponseBody> call, Response<ResponseBody> response) {
progressDialog.dismiss();
//result ok
if (response.code() == 200)
{
try
{
onLoginSuccess.loginResponse(JsonSuccessParser.parseLoginResponse
(context, response.body().string()));
} catch (IOException e)
{
e.printStackTrace();
}
}
else if (response.code() == 403)
{
onLoginSuccess.loginError(response.code());
}
else
{
try
{
JsonErrorParser.parseServerError(context,response.errorBody().string());
} catch (IOException e)
{
e.printStackTrace();
}
}
}
#Override
public void onFailure(Call<ResponseBody> call, Throwable t) {
progressDialog.dismiss();
showNoConnectionDialog(context);
}
});
} else {
progressDialog.dismiss();
showNoConnectionDialog(context);
}
}
This is my code for setting language abbreviation in shared preferences
private void setUserLocale()
{
String selected_country = countryCodeAdapter.getItem(country_code_spinner.
getSelectedItemPosition()).language.abbreviation.toLowerCase();
LocaleHelper.setLocale(this,selected_country);
}
How can I change header immediately when user change spinner position?

In ApiClient class, you should initialize locale variable inside of interceptor methods to reflect your changes.
Example)
private static final String BASE_URL = ApiUrls.server_url;
public static Retrofit getClient(Context context)
{
OkHttpClient.Builder httpClient = new OkHttpClient.Builder();
httpClient = httpClient.addInterceptor(new Interceptor() {
#Override
public Response intercept(Chain chain) throws IOException
{
SharedPrefUtil sharedPrefUtil = new SharedPrefUtil(context);
String locale = sharedPrefUtil.getSelectedLanguage();
Request request = chain.request().newBuilder().header("Accept-Language",
locale).build();
return chain.proceed(request);
}
});
Retrofit retrofit = new Retrofit.Builder().baseUrl(BASE_URL)
.addConverterFactory(GsonConverterFactory.create()).client(httpClient.build())
.build();
return retrofit;
}
However, if the value changes constantly, it may be possible to explicitly pass the value of the Header as an argument to the Service instead of the Interceptor.
Example)
public interface ApiService {
Call<...> loginRequest(#Header("Accept-Language") String language, #QueryMap Map<String, String> params);
}
public static void sendLogin(final Context context, Map<String, String> params,
final HttpResponses.onLoginSuccess onLoginSuccess) {
DialogHelper.ProgressDialog progressDialog = showWaitDialog(context);
if (hasInternetConnection(context)) {
params.put("grant_type", "password");
params.put("client_id", "raymon-client");
params.put("client_secret", "raymon-secret");
SharedPrefUtil sharedPrefUtil = new SharedPrefUtil(context);
String locale = sharedPrefUtil.getSelectedLanguage();
ApiInterface apiService = ApiClient.getClient(context).create(ApiInterface.class);
Call<ResponseBody> call = apiService.loginRequest(locale, params);
call.enqueue(new Callback<ResponseBody>() {
#Override
public void onResponse(Call<ResponseBody> call, Response<ResponseBody> response) {
progressDialog.dismiss();
//result ok
if (response.code() == 200)
{
try
{
onLoginSuccess.loginResponse(JsonSuccessParser.parseLoginResponse
(context, response.body().string()));
} catch (IOException e)
{
e.printStackTrace();
}
}
else if (response.code() == 403)
{
onLoginSuccess.loginError(response.code());
}
else
{
try
{
JsonErrorParser.parseServerError(context,response.errorBody().string());
} catch (IOException e)
{
e.printStackTrace();
}
}
}
#Override
public void onFailure(Call<ResponseBody> call, Throwable t) {
progressDialog.dismiss();
showNoConnectionDialog(context);
}
});
} else {
progressDialog.dismiss();
showNoConnectionDialog(context);
}
}

How to fix Expected BEGIN_OBJECT but was STRING in Retrofit? [duplicate]

This question already has an answer here:
How to fix Expected BEGIN_OBJECT in Retrofit?
(1 answer)
Closed 4 years ago.
In my application i want use Retrofit for get some data from server.
I write below codes but when run application and call api show me below error :
E/socketLogResponse: Err : com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected BEGIN_OBJECT but was STRING at line 1 column 1 path $
Please see my above codes and help me
API response from server :
{
"status": "ok",
"time": 0.014972925186157227
}
ApiService interface :
#POST("api/log")
Call<SocketPingResponse> getSocketPingLog(#Header("jwt") String jwt, #Body SocketPingBodySendData socketPingBodySendData);
SocketPingResponse class :
public class SocketPingResponse {
#SerializedName("status")
#Expose
private String status;
#SerializedName("time")
#Expose
private Double time;
public String getStatus() {
return status;
}
public void setStatus(String status) {
this.status = status;
}
public Double getTime() {
return time;
}
public void setTime(Double time) {
this.time = time;
}
}
SocketPingBodySendData class :
public class SocketPingBodySendData {
#SerializedName("auction_id")
#Expose
int auction_id;
#SerializedName("data")
#Expose
List<SocketPingEntity> data;
public int getAuction_id() {
return auction_id;
}
public void setAuction_id(int auction_id) {
this.auction_id = auction_id;
}
public List<SocketPingEntity> getData() {
return data;
}
public void setData(List<SocketPingEntity> data) {
this.data = data;
}
}
Api call codes in activity :
pingEntityList.addAll(socketPingDatabase.socketPingDao().getSocketPingEntityList());
SocketPingBodySendData pingBodySendData = new SocketPingBodySendData();
pingBodySendData.setAuction_id(auctionID);
pingBodySendData.setData(pingEntityList);
Toast.makeText(context, ""+pingEntityList.size(), Toast.LENGTH_SHORT).show();
Call<SocketPingResponse> pingResponseCall = apis.getSocketPingLog(jwtToken, pingBodySendData);
pingResponseCall.enqueue(new Callback<SocketPingResponse>() {
#Override
public void onResponse(Call<SocketPingResponse> call, Response<SocketPingResponse> response) {
if (response.body() != null) {
Toast.makeText(context, response.body().getStatus(), Toast.LENGTH_SHORT).show();
if (response.body().getStatus().equals("ok")) {
pingEntityList.clear();
socketPingDatabase.socketPingDao().deleteAll();
}
}
}
#Override
public void onFailure(Call<SocketPingResponse> call, Throwable t) {
Log.e("socketLogResponse", "Err : " + t.toString());
}
});
ApiClient class :
public class ApiClient {
private static final String BASE_URL = Constants.SERVER;
private static Retrofit retrofit = null;
private static Context context;
public static Retrofit getClient() {
HttpLoggingInterceptor interceptor = new HttpLoggingInterceptor();
interceptor.setLevel(HttpLoggingInterceptor.Level.BODY);
OkHttpClient.Builder client = new OkHttpClient.Builder();
client.interceptors().add(interceptor);
client.addInterceptor(new Interceptor() {
#Override
public Response intercept(Chain chain) throws IOException {
Request request = chain.request().newBuilder().addHeader("X-Client-Version", Constants.getAppVersionName()).build();
return chain.proceed(request);
}
});
client.addInterceptor(new Interceptor() {
#Override
public Response intercept(Chain chain) throws IOException {
Request request = chain.request().newBuilder().addHeader("uuid", Constants.getUUID(Constants.currentActivity)).build();
return chain.proceed(request);
}
});
client.addInterceptor(new Interceptor() {
#Override
public Response intercept(Chain chain) throws IOException {
Request request = chain.request().newBuilder().addHeader("agent", Constants.getAgent()).build();
return chain.proceed(request);
}
});
OkHttpClient client2 = client
.connectTimeout(60, TimeUnit.SECONDS)
.writeTimeout(60, TimeUnit.SECONDS)
.readTimeout(60, TimeUnit.SECONDS)
.build();
Gson gson = new GsonBuilder()
.setLenient()
.create();
if (retrofit == null) {
retrofit = new Retrofit.Builder()
.baseUrl(BASE_URL)
.addConverterFactory(GsonConverterFactory.create(gson))
.client(client2)
.build();
}
return retrofit;
}
}
How can i fix this issue?

I think the problem returns string when no data is returned. Backend can usually do such errors. this error had happened to me before. you should check the response json when no data is available

Retrofit is typesafe library. It means that it waits only particular (predefined) types of objects. If server sends something else - it crashes with error. This is your case. Just check raw server response and you'll see what's wrong.

Try changing your API call
from
#POST("api/log")
Call<SocketPingResponse> getSocketPingLog(#Header("jwt") String jwt, #Body SocketPingBodySendData socketPingBodySendData);
to
#POST("api/log")
Call<String> getSocketPingLog(#Header("jwt") String jwt, #Body SocketPingBodySendData socketPingBodySendData);
pingEntityList.addAll(socketPingDatabase.socketPingDao().getSocketPingEntityList());
SocketPingBodySendData pingBodySendData = new SocketPingBodySendData();
pingBodySendData.setAuction_id(auctionID);
pingBodySendData.setData(pingEntityList);
Toast.makeText(context, ""+pingEntityList.size(), Toast.LENGTH_SHORT).show();
Call<String> pingResponseCall = apis.getSocketPingLog(jwtToken, pingBodySendData);
pingResponseCall.enqueue(new Callback<String>() {
#Override
public void onResponse(Call<String> call, Response<String> response) {
if (response.body() != null) {
//Convert here your string response to Other POJO format
}
}
#Override
public void onFailure(Call<String> call, Throwable t) {
Log.e("socketLogResponse", "Err : " + t.toString());
}
});

Retrofit: Redirect to LoginActivity if response code is 401

How to start LoginActivity from the interceptor(non-activity class)? I have tried the code (Interceptor) below but not working for me.
Interceptor
OkHttpClient client = new OkHttpClient.Builder().addInterceptor(new Interceptor() {
#Override
public Response intercept(Chain chain) throws IOException {
Request newRequest = chain.request().newBuilder()
.addHeader("Authorization", "Bearer " + auth_token_string)
.build();
Response response = chain.proceed(newRequest);
Log.d("MyApp", "Code : "+response.code());
if (response.code() == 401){
Intent intent = new Intent(SplashActivity.getContextOfApplication(), LoginActivity.class);
startActivity(intent);
finish(); //Not working
return response;
}
return chain.proceed(newRequest);
}
}).build();
This is the current solution I'm using, is there any better solution than this? This solution has to keep repeat on every api call.
MainActivity
call.enqueue(new Callback<Token>() {
#Override
public void onResponse(Call<Token> call, Response<Token> response) {
if(response.isSuccessful())
{
//success
}
else
{
Intent intent = new Intent(MainActivity.this.getApplicationContext(), LoginActivity.class);
startActivity(intent);
finish();
}
}
#Override
public void onFailure(Call<Token> call, Throwable t) {
}
});

Personally, I would like to suggest using event bus pattern here. You can use greenrobot implementation or whatever you want, since it's more about an architecture approach rather than concrete implementation.
Create event model
public class UnauthorizedEvent {
private static final UnauthorizedEvent INSTANCE = new UnauthorizedEvent();
public static UnauthorizedEvent instance() {
return INSTANCE;
}
private UnauthorizedEvent() {
}
}
Implement custom Interceptor which disptaches event about unauthorized reqeusts
class UnauthorizedInterceptor implements Interceptor {
#Override
public Response intercept(#NonNull Chain chain) throws IOException {
Response response = chain.proceed(chain.request());
if (response.code() == 401) {
EventBus.getDefault().post(UnauthorizedEvent.instance());
}
return response;
}
}
Create BaseActivity class which handles UnauthorizedEvent
public class BaseActivity extends Activity {
#Override
public void onStart() {
super.onStart();
EventBus.getDefault().register(this);
}
#Override
public void onStop() {
super.onStop();
EventBus.getDefault().unregister(this);
}
#Subscribe
public final void onUnauthorizedEvent(UnauthorizedEvent e) {
handleUnauthorizedEvent();
}
protected void handleUnauthorizedEvent() {
Intent intent = new Intent(this, LoginActivity.class);
startActivity(intent);
}
}
Prevent launching LoginActivity from LoginActivity
public class LoginActivty extends BaseActivity {
#Override
protected void handleUnauthorizedEvent() {
//Don't handle unauthorized event
}
}
Another approach is to not extending BaseActivity here.
Register your interceptor
OkHttpClient client = new OkHttpClient.Builder()
.addInterceptor(new UnauthorizedInterceptor())
.build();
Pros:
Loose coupling between components
Easaly extending the logic by overriding handleUnauthorizedEvent
No need to rewrite code to use new types of callbacks
Reduce human factor about making mistakes (using Callback instead of BaseCallback)
Cons:
EventBus pattern makes debugging more complicated
One more dependency or own implementation which brings new code to the project
Also, please take into account, that this example doesn't cover multithreading issues. It solves your problem of handling unauthorized requests. Thus, if two requests receive 401 than it is possible that 2 instances of LoginActivity is started.

Consider introducing a custom implementation of retrofit2.Callback interface, e.g. BaseCallback:
public abstract class BaseCallback<T> implements Callback<T> {
private final Context context;
public BaseCallback(Context context) {
this.context = context;
}
#Override
public void onResponse(Call<T> call, Response<T> response) {
if (response.code() == 401) {
// launch login activity using `this.context`
} else {
onSuccess(response.body());
}
}
#Override
public void onFailure(Call<T> call, Throwable t) {
}
abstract void onSuccess(T response);
}
Now, from the caller site you should change new Callback<Token> with new BaseCallback<Token>:
call.enqueue(new BaseCallback<Token>(context) {
#Override
void onSuccess(Token response) {
// do something with token
}
});
Although, this approach doesn't fulfil your following statement:
so I don't have to keep repeat the same code over again for each api call
nevertheless, I cannot come up with a better approach.

The simplest way is to inject activity context in Interceptor instance.
If you are using some DI tools, like Dagger2 or Toothpick it will be very simple. I recommend to use toothpick)
https://github.com/stephanenicolas/toothpick
The most code near by will be in kotlin, because it's my boilerplate code. Those thinks, that you are need to solve your problem i will write in Java.
The solution will be like this:
#Qualifier
annotation class BackendUrl
class ActivityModule(activity: BaseActivity): Module() {
init {
bind(Activity::class.java).toInstance(activity)
}
}
class NetworkModule: Module() {
init {
bind(String::class.java).withName(BackendUrl::class.java).toInstance(Constants.URL)
bind(Gson::class.java).toInstance(GsonBuilder().setDateFormat("yyyy-MM-dd'T'HH:mm:ss").create())
bind(CacheHolder::class.java).toProvider(CacheProvider::class.java).singletonInScope()
bind(OkHttpClient::class.java).toProvider(OkHttpProvider::class.java).instancesInScope()
bind(BackendApi::class.java).toProvider(BackendApiProvider::class.java).instancesInScope()
bind(RedirectInterceptor::class.java).to(RedirectInterceptor::class.java)
}
}
Than you need to create Providers for injection dependency
class BackendApiProvider #Inject constructor(
private val okHttpClient: OkHttpClient,
private val gson: Gson,
#BackendUrl private val serverPath: String
) : Provider<BackendApi> {
override fun get() =
Retrofit.Builder()
.addConverterFactory(GsonConverterFactory.create(gson))
.addCallAdapterFactory(RxJava2CallAdapterFactory.create())
.client(okHttpClient)
.baseUrl(serverPath)
.build()
.create(BackendApi::class.java)
}
And your redirect interceptor:
public class RedirectInterceptor implements Interceptor {
private final Context context;
#Inject
public RedirectInterceptor(Activity context) {
this.context = context;
}
#Override
public Response intercept(Chain chain) throws IOException {
Request newRequest = chain.request().newBuilder()
.build();
Response response = chain.proceed(newRequest);
Log.d("MyApp", "Code : "+response.code());
if (response.code() == 401){
Intent intent = new Intent(context, LoginActivity.class);
context.startActivity(intent);
((Activity) context).finish();
return response;
}
return chain.proceed(newRequest);
}
}
Oh, yes. For Authorization header will be better to create new instance of another interceptor
class HeaderInterceptor(private val token: String?) : Interceptor {
#Throws(IOException::class)
override fun intercept(chain: Interceptor.Chain): Response {
val request = chain.request()
val newRequest = request.newBuilder()
Log.d(TAG, "token: $token")
if (token != null && token.isNotBlank()) {
newRequest.addHeader("Authorization", "Bearer $token")
}
return chain.proceed(newRequest.build())
}
companion object {
private val TAG = HeaderInterceptor::class.java.toString()
}
}
And your OkhttpProvder
class OkHttpProvider #Inject constructor(cacheHolder: CacheHolder, prefs: IPreferences, redirectInterceptor: RedirectInterceptor) : Provider<OkHttpClient> {
private val client: OkHttpClient
init {
val builder = OkHttpClient.Builder()
builder
.addNetworkInterceptor(redirectInterceptor)
.addNetworkInterceptor(HeaderInterceptor(prefs.getAuthToken()))
.readTimeout(30, TimeUnit.SECONDS)
.cache(cacheHolder.okHttpCache)
client = builder.build()
}
override fun get() = client
}
Thats all! Now, you just only need to place you modules in right scopes.
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.init_view)
Toothpick.openScopes("activity scope").apply {
installModules(ActivityModule(this#YourActivity))
Toothpick.inject(this#YourActivity, this)
}
Toothpick.openScopes("activity scope", "network scope").apply {
installModules(NetworkModule())
}
// your activity code
}

This is how interceptor worked for handling 401 globally
public class ResponseHeaderInterceptor implements Interceptor {
private final Context context;
public ResponseHeaderInterceptor(Context context) {
this.context = context;
}
#NotNull
#Override
public Response intercept(#NotNull Chain chain) throws IOException {
Response response = chain.proceed(chain.request());
if(response.code() == 401){
SharedPreferences pref = context.getSharedPreferences(Constants.PREFERENCES, 0);
String userName = pref.getString("key_user_email", "");
//clear shared preferences
pref.edit().clear().apply();
Bundle params = new Bundle();
params.putString("user", userName);
FirebaseAnalytics.getInstance(context).logEvent(Constants.USER_UNAUTHORIZED_EVENT, params);
Intent intent = new Intent(this.context, IntroActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
this.context.startActivity(intent);
}
return response;
}
}
adding to okhttp client of retrofit
var okHttpClient: OkHttpClient = OkHttpClient()
.newBuilder()
.addInterceptor(ResponseHeaderInterceptor(MyApplication.getMyApplicationContext()))//Header interceptor for logging network responses
.build()
private var retrofit: Retrofit? = null
val client: Retrofit?
get() {
if (retrofit == null) {
retrofit = Retrofit.Builder()
.client(okHttpClient)
.baseUrl(BuildConfig.SERVER)
.addConverterFactory(GsonConverterFactory.create())
.build()
}
return retrofit
}

Generalized Solution:
You can solve it by generalizing the error handling. You can use custom CallAdapterFactory to the Retrofit builder. Please refer below classes :
RxErrorHandlingCallAdapterFactory :
public class RxErrorHandlingCallAdapterFactory extends CallAdapter.Factory {
private static Context mContext = null;
private final RxJava2CallAdapterFactory original;
private RxErrorHandlingCallAdapterFactory() {
original = RxJava2CallAdapterFactory.create();
}
public static CallAdapter.Factory create(Context context) {
mContext = context;
return new RxErrorHandlingCallAdapterFactory();
}
#Override
public CallAdapter<?, ?> get(Type returnType, Annotation[] annotations, Retrofit retrofit) {
return new RxCallAdapterWrapper(retrofit, original.get(returnType, annotations, retrofit));
}
private static class RxCallAdapterWrapper<R> implements CallAdapter<R, Object> {
private final Retrofit retrofit;
private final CallAdapter<R,
Object> wrapped;
public RxCallAdapterWrapper(Retrofit retrofit, CallAdapter<R, Object> wrapped) {
this.retrofit = retrofit;
this.wrapped = wrapped;
}
#Override
public Type responseType() {
return wrapped.responseType();
}
#Override
public Object adapt(Call<R> call) {
Object result = wrapped.adapt(call);
if (result instanceof Single) {
return ((Single) result).onErrorResumeNext(new Function<Throwable, SingleSource>() {
#Override
public SingleSource apply(#NonNull Throwable throwable) throws Exception {
return Single.error(asRetrofitException(throwable));
}
});
}
if (result instanceof Observable) {
return ((Observable) result).onErrorResumeNext(new Function<Throwable, ObservableSource>() {
#Override
public ObservableSource apply(#NonNull Throwable throwable) throws Exception {
return Observable.error(asRetrofitException(throwable));
}
});
}
if (result instanceof Completable) {
return ((Completable) result).onErrorResumeNext(new Function<Throwable, CompletableSource>() {
#Override
public CompletableSource apply(#NonNull Throwable throwable) throws Exception {
return Completable.error(asRetrofitException(throwable));
}
});
}
return result;
}
private RetrofitException asRetrofitException(Throwable throwable) {
// We had non-200 http error
Log.v("log", "eror");
throwable.printStackTrace();
if (throwable instanceof HttpException) {
HttpException httpException = (HttpException) throwable;
final Response response = httpException.response();
//if ((mContext instanceof Activity)) {
String s = "Something went wrong."; //mContext.getString(R.string.something_went_wrong);
try {
s = new JSONObject(response.errorBody().string()).getString("message");
if (response.code() == 401) { // 401 Unauthorized
Intent intent = new Intent(mContext, LoginActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
mContext.startActivity(intent);
}
} catch (JSONException | IOException e) {
e.printStackTrace();
}
return RetrofitException.unexpectedError(s, response, retrofit);
//showErrorDialog(mContext, response);
//}
// return RetrofitException.httpError(response.errorBody().toString(), response, retrofit);
}
// A network error happened
if (throwable instanceof IOException) {
return RetrofitException.networkError((IOException) throwable);
}
// We don't know what happened. We need to simply convert to an unknown error
return RetrofitException.unexpectedError(throwable);
}
}
}
RetrofitException :
public class RetrofitException extends RuntimeException {
private final String url;
private final Response response;
private final Kind kind;
private final Retrofit retrofit;
RetrofitException(String message, String url, Response response, Kind kind, Throwable exception, Retrofit retrofit) {
super(message, exception);
this.url = url;
this.response = response;
this.kind = kind;
this.retrofit = retrofit;
}
public static RetrofitException httpError(String url, Response response, Retrofit retrofit) {
String message = response.code() + " " + response.message();
return new RetrofitException(message, url, response, Kind.HTTP, null, retrofit);
}
public static RetrofitException networkError(IOException exception) {
return new RetrofitException(exception.getMessage(), null, null, Kind.NETWORK, exception, null);
}
public static RetrofitException unexpectedError(Throwable exception) {
return new RetrofitException(exception.getMessage(), null, null, Kind.UNEXPECTED, exception, null);
}
public static RetrofitException unexpectedError(String s, Response response, Retrofit retrofit) {
return new RetrofitException(s, null, null, Kind.UNEXPECTED, null, null);
}
/**
* The request URL which produced the error.
*/
public String getUrl() {
return url;
}
/**
* Response object containing status code, headers, body, etc.
*/
public Response getResponse() {
return response;
}
/**
* The event kind which triggered this error.
*/
public Kind getKind() {
return kind;
}
/**
* The Retrofit this request was executed on
*/
public Retrofit getRetrofit() {
return retrofit;
}
/**
* HTTP response body converted to specified {#code type}. {#code null} if there is no
* response.
*
* #throws IOException if unable to convert the body to the specified {#code type}.
*/
public <T> T getErrorBodyAs(Class<T> type) throws IOException {
if (response == null || response.errorBody() == null) {
return null;
}
Converter<ResponseBody, T> converter = retrofit.responseBodyConverter(type, new Annotation[0]);
return converter.convert(response.errorBody());
}
/**
* Identifies the event kind which triggered a {#link RetrofitException}.
*/
public enum Kind {
/**
* An {#link IOException} occurred while communicating to the server.
*/
NETWORK,
/**
* A non-200 HTTP status code was received from the server.
*/
HTTP,
/**
* An internal error occurred while attempting to execute a request. It is best practice to
* re-throw this exception so your application crashes.
*/
UNEXPECTED
}
}
Retrofit Builder :
Retrofit retrofit = new Retrofit.Builder()
.addCallAdapterFactory(RxErrorHandlingCallAdapterFactory.create(context))
.addConverterFactory(GsonConverterFactory.create())
.baseUrl(API_URL)
.client(client)
.build();
You can handle 401 in RxErrorHandlingCallAdapterFactory and other errors through Throwable.

Can't update member variable

Somehow line mResponseText = response.body().string(); isn't writing member variable. Instead it appears to be creating and logging it locally.
Any ideas why? The more I look at it the more clueless I'm getting :(
public class Gateway {
private static final String TAG = Gateway.class.getSimpleName();
public static final MediaType JSON
= MediaType.parse("application/json; charset=utf-8");
private String mResponseText = "[{'comment' : 'fake' , 'psn_nickname' : 'fake', 'created':'now', 'parent_class':''}]";
public Gateway (String url, String json, final Context context) {
if(isNetworkAvailable(context)) {
//if network is available build request
OkHttpClient client = new OkHttpClient();
// RequestBody body = RequestBody.create(JSON, json);
Request request = new Request.Builder()
.url(url)
//.post(body)
.build();
Call call = client.newCall(request);
call.enqueue(new Callback() {
//execute call
#Override
public void onFailure(Request request, IOException e) {
// if request failed
Toast.makeText(context, "request failed", Toast.LENGTH_LONG).show();
}
#Override
public void onResponse(Response response) throws IOException {
// if succeeded
if(response.isSuccessful()){
mResponseText = response.body().string();
Log.v(TAG, "SETTING RESPONSE");
// THIS LOGS PROPER JSON LOADED FROM NETWORK
Log.v(TAG, mResponseText);
} else {
//alertUserAboutError(context);
Toast.makeText(context, "Something wrong with response", Toast.LENGTH_LONG).show();
}
}
});
} else {
Toast.makeText(context, "Network is not available", Toast.LENGTH_LONG).show();
}
}
public String getResponse () {
Log.v(TAG, "GETTING RESPONSE");
// THIS LOGS FAKE SAMPLE JSON --- WTF???
Log.v(TAG, mResponseText);
return mResponseText;
}
// check if network is available
private boolean isNetworkAvailable(Context c) {
ConnectivityManager manager = (ConnectivityManager) c.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo networkInfo = manager.getActiveNetworkInfo();
boolean isAvailable = false;
if (networkInfo != null && networkInfo.isConnected()) {
isAvailable = true;
}
return isAvailable;
}
/*
private void alertUserAboutError(Context c) {
AlertDialogFragment dialog = new AlertDialogFragment();
dialog.show(c.getFragmentManager(), "error_dialog");
}
*/
}
Here's the code that's using this class
Gateway gateway = new Gateway(mCommentURL, "", this);
String mJsonData = gateway.getResponse();
EDIT Code update - removed extends Activity

You're calling getResponse() too early. The async operation has not completed yet and the value returned is the one you initialize there in the first place, not the one written in the Callback.
Put the code that uses the response in the Callback, or call that code from the callback.