问题
So when I make a POST API call to my server, I get a 400 Bad Request error with JSON response.
{
"userMessage": "Blah",
"internalMessage": "Bad Request blah blah",
"errorCode": 1
}
I call it by
Call.enqueue(new Callback<ResponseBody>() {
@Override
public void onResponse(Call<ResponseBody> call, Response<ResponseBody> response) {
//AA
}
@Override
public void onFailure(Call<ResponseBody> call, Throwable t) {
//BB
}
}
However the problem is that once I get the response, onFailure() is invoke so that //BB is called. Here, I have no way to access the JSON response. When I log the api request and response, it doesn't show JSON response at all. And Throwable t is IOException. However, strangely, when I make the same call on Postman, it does return the expected JSON response with 400 error code.
So my question is how can I get the json response when I get 400 Bad Request error? Should I add something to okhttpclient?
Thanks
回答1:
You can do it like in your onResponse method, remember 400 is a response status not an error:
if (response.code() == 400) {
Log.v("Error code 400",response.errorBody().string());
}
And you can handle any response code except 200-300 with Gson like :
if (response.code() == 400) {
Gson gson = new GsonBuilder().create();
ErrorPojoClass mError=new ErrorPojoClass();
try {
mError= gson.fromJson(response.errorBody().string(),ErrorPojoClass .class);
Toast.makeText(getApplicationContext(), mError.getErrorDescription(), Toast.LENGTH_LONG).show();
} catch (IOException e) {
// handle failure to read error
}
}
Add this to your build.gradle : compile 'com.google.code.gson:gson:2.7'
If you want create Pojo class go to Json Schema 2 Pojo and paste your example Json response. Select source type Json and annotation Gson .
回答2:
You can try the below code to get 400 response. You can get error response from errorBody() method.
Call.enqueue(new Callback<ResponseBody>() {
@Override
public void onResponse(Call<ResponseBody> call, Response<ResponseBody> response) {
//get success and error response here
if (response.code() == 400) {
if(!response.isSuccessful()) {
JSONObject jsonObject = null;
try {
jsonObject = new JSONObject(response.errorBody().string());
String userMessage = jsonObject.getString("userMessage");
String internalMessage = jsonObject.getString("internalMessage");
String errorCode = jsonObject.getString("errorCode");
} catch (JSONException e) {
e.printStackTrace();
}
}
}
@Override
public void onFailure(Call<ResponseBody> call, Throwable t) {
//get failure response here
}
}
}
EDIT: Fixed method name from toString to string
回答3:
I got similar issue, but existing code was stick to RxJava 2 chain. Here's my solution:
public static <T> Observable<T> rxified(final Call<T> request, final Class<T> klazz) {
return Observable.create(new ObservableOnSubscribe<T>() {
AtomicBoolean justDisposed = new AtomicBoolean(false);
@Override
public void subscribe(final ObservableEmitter<T> emitter) throws Exception {
emitter.setDisposable(new Disposable() {
@Override
public void dispose() {
request.cancel();
justDisposed.set(true);
}
@Override
public boolean isDisposed() {
return justDisposed.get();
}
});
if (!emitter.isDisposed())
request.enqueue(new Callback<T>() {
@Override
public void onResponse(Call<T> call, retrofit2.Response<T> response) {
if (!emitter.isDisposed()) {
if (response.isSuccessful()) {
emitter.onNext(response.body());
emitter.onComplete();
} else {
Gson gson = new Gson();
try {
T errorResponse = gson.fromJson(response.errorBody().string(), klazz);
emitter.onNext(errorResponse);
emitter.onComplete();
} catch (IOException e) {
emitter.onError(e);
}
}
}
}
@Override
public void onFailure(Call<T> call, Throwable t) {
if (!emitter.isDisposed()) emitter.onError(t);
}
});
}
});
}
transforming 400-like responses into rx chain is pretty simple:
Call<Cat> request = catApi.getCat();
rxified(request, Cat.class).subscribe( (cat) -> println(cat) );
回答4:
public void onResponse(Call<ResponseBody> call, Response<ResponseBody> response) {
DialogHelper.dismiss();
if (response.isSuccessful()) {
// Success
} else {
try {
JSONObject jObjError = new JSONObject(response.errorBody().string());
Toast.makeText(getContext(), jObjError.getString("message"), Toast.LENGTH_LONG).show();
} catch (Exception e) {
Toast.makeText(getContext(), e.getMessage(), Toast.LENGTH_LONG).show();
}
}
}
回答5:
First step:
Create your POJO class for error response. In my case, ApiError.java
public class ApiError {
@SerializedName("errorMessage")
@Expose
private String errorMessage;
public String getErrorMessage() {
return errorMessage;
}
public void setErrorMessage(String errorMessage) {
this.errorMessage= errorMessage;
}
}
Second Step:
Write below code in your api callback.
Call.enqueue(new Callback<RegistrationResponse>() {
@Override
public void onResponse(Call<RegistrationResponse> call, Response<RegistrationResponse> response)
{
if (response.isSuccessful()) {
// do your code here
} else if (response.code() == 400) {
Converter<ResponseBody, ApiError> converter =
ApiClient.retrofit.responseBodyConverter(ApiError.class, new Annotation[0]);
ApiError error;
try {
error = converter.convert(response.errorBody());
Log.e("error message", error.getErrorMessage());
Toast.makeText(context, error.getErrorMessage(), Toast.LENGTH_LONG).show();
} catch (IOException e) {
e.printStackTrace();
}
}
}
@Override
public void onFailure(Call<RegistrationResponse> call, Throwable t) {
//do your failure handling code here
}
}
Here ApiClient.retrofit is your retrofit instance which is static.
回答6:
This is how you can handle the response message I am handling for error 500 you can add as much you want
switch (response.code()) {
case HttpURLConnection.HTTP_OK:
break;
case HttpURLConnection.HTTP_UNAUTHORIZED:
callback.onUnAuthentic();
break;
case HttpURLConnection.HTTP_INTERNAL_ERROR:
try {
String errorResponse = response.errorBody().string();
JSONObject object = new JSONObject(errorResponse);
String message = "Error";
if (object.has("Message"))
message = String.valueOf(object.get("Message"));
callback.onError(message);
} catch (IOException e) {
e.printStackTrace();
}
break;
case HttpURLConnection.HTTP_GATEWAY_TIMEOUT:
case HttpURLConnection.HTTP_CLIENT_TIMEOUT:
default:
callback.onNetworkError();
break;
}
来源：https://stackoverflow.com/questions/38255291/retrofit-2-0-how-to-get-response-body-for-400-bad-request-error