retofit2 how to post plain String in body

Question

I'm using retrofit2

com.squareup.retrofit2:retrofit:2.0.1

My rest API(Post) returns plain string as response

how to post String in body?

My code is

I'm using custom String Converter Factory

public final class ToStringConverterFactory extends Converter.Factory {
        @Override
        public Converter<ResponseBody, ?> responseBodyConverter(Type type, Annotation[] annotations, Retrofit retrofit) {
            //noinspection EqualsBetweenInconvertibleTypes
            if (String.class.equals(type)) {
                return new Converter<ResponseBody, Object>() {

                    @Override
                    public Object convert(ResponseBody responseBody) throws IOException {
                        return responseBody.string();
                    }
                };
            }

            return null;
        }

        @Override
        public Converter<?, RequestBody> requestBodyConverter(Type type, Annotation[] parameterAnnotations, Annotation[] methodAnnotations, Retrofit retrofit) {
            if (String.class.equals(type)) {
                return new Converter<String, RequestBody>() {

                    @Override
                    public RequestBody convert(String value) throws IOException {
                        return RequestBody.create(MediaType.parse("text/plain"), value);
                    }
                };
            }

            return null;
        }


    }

and my Retrofit builder is

Retrofit retrofit = new Retrofit.Builder().baseUrl(root_url).addConverterFactory(new ToStringConverterFactory()).build();

and my callback is

Callback<String>  callback = new Callback<String>() {
            @Override
            public void onResponse(Call<String> call, Response<String> response) {



                System.out.println("===>>> onResponse body res "+response.body());
                System.out. println("===>>> onResponse error body res "+response.errorBody());

            }

            @Override
            public void onFailure(Call<String> call, Throwable t) {
                System.out.println("===>>> onFailure "+call.toString()+" "+t.toString());
                t.printStackTrace();
            }
        };

My RetroService interface is

public interface RetroService {


    @POST("/validateUser")
    Call<String> login(@Body String body);

}

and the API call

Call<String> loginCall = service.login(req);
                    loginCall.enqueue(callback);

What i'm getting is in onresponse() response.body its always showing as null.

Please clarify what i'm doing wrong.

Thx in adv.

why do you use converter? and are you sure the server is sending back respose? — Uriel Frankel

xiaoyaoworm xiaoyaoworm · Accepted Answer · 2016-04-12T19:00:37

I google online, finding that latest GSON can handle plain text response. Add this into gradle:

compile 'com.google.code.gson:gson:2.6.2'
compile 'com.squareup.okhttp3:okhttp:3.1.2'
compile 'com.squareup.retrofit2:converter-gson:2.0.1'
compile 'com.squareup.okhttp3:logging-interceptor:3.2.0'

Using this in your code

import com.google.gson.Gson;
import okhttp3.OkHttpClient;
import okhttp3.logging.HttpLoggingInterceptor;
import retrofit2.Retrofit;
import retrofit2.converter.gson.GsonConverterFactory;

// Add log
HttpLoggingInterceptor logging = new HttpLoggingInterceptor();
logging.setLevel(HttpLoggingInterceptor.Level.BODY);
OkHttpClient.Builder httpClient = new OkHttpClient.Builder();
httpClient.interceptors().add(logging);

Gson gson = new GsonBuilder()
                    .setDateFormat("yyyy-MM-dd'T'HH:mm:ssZ")
                    .create();

Retrofit retrofit = new Retrofit.Builder()
            .baseUrl(root_url)
            .addConverterFactory(GsonConverterFactory.create(gson))
            .addCallAdapterFactory(RxJavaCallAdapterFactory.create())
            .client(httpClient.build())
            .build();

Please give a try to see whether you can handle String in response.

This is what I find online, not sure whether it is working for u. Please give a try. link

retofit2 how to post plain String in body

1 Answers