Can't POST using Retrofit on Body raw

Question

I want to Post data on API using body raw but always got null on response.body and data not send.

Here is my retrofit class:

public class ApiClient {
public static Retrofit retrofit;
private static final String BASE_URL = BuildConfig.BASE_URL;

public static Retrofit getRetrofitInstance(){
    if (retrofit == null){
        retrofit =  new Retrofit.Builder()
                .baseUrl(BASE_URL)
                .addConverterFactory(GsonConverterFactory.create())
                .build();
    }

    return  retrofit;
}

}

then here is the interface:

public interface SendData {
@POST("/")
Call<DataItem> sendData(@Body DataItem body);}

there is class model:

public class DataItem{
private String date;
private String imgUrl;
private double probability;
private String latitude;
private String longtitude;
private String className;

public DataItem(String date, String imgUrl, double probability, String latitude, String longtitude, String className) {
    this.date = date;
    this.imgUrl = imgUrl;
    this.probability = probability;
    this.latitude = latitude;
    this.longtitude = longtitude;
    this.className = className;
}

public String getDate(){
    return date;
}

public String getImgUrl(){
    return imgUrl;
}

public double getProbability(){
    return probability;
}

public String getLatitude(){
    return latitude;
}

public String getLongtitude(){
    return longtitude;
}

public String getClassName(){
    return className;
}

}

here is call the retrofit to post data:

DataItem data = new DataItem(currentDate, imgUrl, probability, latitude, longitude, class_name);

                    SendData service = ApiClient.getRetrofitInstance().create(SendData.class);
                    Call<DataItem> call = service.sendData(data);
                    call.enqueue(new Callback<DataItem>() {
                        @Override
                        public void onResponse(Call<DataItem> call, Response<DataItem> response) {
                            String result = String.valueOf(response.body());
                            Log.d("MainActivity", "response = " + response.message());
                            Log.d("MainActivity", "result = " + result);
                            timingSendData();
                            Toast.makeText(MainActivity.this, "Data Send!", Toast.LENGTH_SHORT).show();
                        }

                        @Override
                        public void onFailure(Call<DataItem> call, Throwable t) {
                            Log.d(TAG, "onFailure: "+t.getMessage());
                            Log.d(TAG, "onFailure: "+t.getLocalizedMessage());
                            Toast.makeText(MainActivity.this, "Cannot Send Data!", Toast.LENGTH_SHORT).show();
                        }
                    });

I already used serilaizaton in model also I used hashmap<string,string> but still not able to post data. API also tested in postman and it's worked

EDIT: after follow @DinkarKumar suggestion, Post data to API is work. but it makes me confused that the response is not on method onResponse() but on method onFailure(), at least data can be Post to API. PS: I moved the URL of API

@DinkarKumar not error and there is no messsage but data not added in API — Thoriqul Umar
@DinkarKumar no it's not , i already checked. status code = 500 — Thoriqul Umar

DinkarKumar DinkarKumar · Accepted Answer · 2021-05-31T15:53:55

You should either change the className to class_name as that is the real field name, or if you want to stick with className then you should annotate class_name. Something like below, the example is using GSON library syntax.

@SerializedName("class_name")
public String className;

And also your response is not of DataItem it's a String Image Added when I tested the same with Postman.

So I think you should also change the

Call<DataItem> sendData(@Body DataItem body);

to

Call<String> sendData(@Body DataItem body);

Can't POST using Retrofit on Body raw

3 Answers