java.lang.NoClassDefFoundError retrofit2.Utils

Question

I\'m using Retrofit to handle the Serverside Data from Mobile. After Implementing retrofit, I am Getting the below Exception.

What am I doing wrong?

Answer 1

You should make Utils class like this:

public class AppUtil{
public static Retrofit getRetrofitInstance(){
        HttpLoggingInterceptor logging=new HttpLoggingInterceptor();
        if(isEnableLogging)
            logging.setLevel(HttpLoggingInterceptor.Level.BODY);
        else
            logging.setLevel(HttpLoggingInterceptor.Level.NONE);
        Gson gson = new GsonBuilder()
                .setExclusionStrategies(new ExclusionStrategy() {
                    @Override
                    public boolean shouldSkipField(FieldAttributes f) {
                        return f.getDeclaringClass().equals(RealmObject.class);
                    }

                    @Override
                    public boolean shouldSkipClass(Class clazz) {
                        return false;
                    }
                })
                .create();
        OkHttpClient.Builder httpClient = new OkHttpClient.Builder();
        httpClient.addInterceptor(logging);

        return new Retrofit.Builder()
                .baseUrl(Constants.URL_BASE_URL)
                .addConverterFactory(GsonConverterFactory.create(gson))
                .client(httpClient.build())
                .build();

    }



}

Create an interface like this for the http methods:

public interface EndPointInterface{
 @FormUrlEncoded
    @POST(Constants.URL_LOGON)
    Call login(@Field(Constants.EMAIL) String email,
                       @Field(Constants.PASSWORD) String password);
} 

In your activity where you are calling the webservices,please proceed like this:

 @OnClick(R.id.btn_login)
    public void onLoginButtonClick() {
        String emailString = edtEmail.getText().toString().trim();
        String passwordString = edtPassword.getText().toString().trim();

        if (emailString.length() == 0) {
            emailWrapper.setError("Please enter E-Mail ID");
        } else if (!AppUtil.isEmailValid(emailString)) {
            emailWrapper.setError("Please enter valid E-Mail ID");
        } else if (passwordString.length() == 0) {
            passwordWrapper.setError("Please enter password");
        } else if (AppUtil.isNetworkConnectionAvailable(this, true)) {
            login(emailString,passwordString);
        }
    }

 private void login(String email, String pwd) {
        final MaterialDialog dialog = AppUtil.showIndeterminateProgressDialog(this,getString(R.string.please_wait));
        EndPointInterface apiService = AppUtil.getRetrofitInstance().create(EndPointInterface.class);
        Call call = apiService.login(email, pwd);
        call.enqueue(new Callback() {
            @Override
            public void onResponse(Call call, Response response) {
                dialog.dismiss();
                if (response.code() == 200) {
                    Doctor doctor = response.body();
                    if (doctor == null) {
                        AppUtil.showSimpleDialog(LoginActivity.this, getString(R.string.userid_pwd_mismatched),
                                getString(R.string.login_credential_mismatch));
                    } else {
                        SharedPreferences.Editor editor = mAppPreferences.edit();
                        editor.putString(Constants.SETTINGS_OBJ_DOCTOR, new Gson().toJson(doctor));
                        editor.putBoolean(Constants.SETTINGS_IS_LOGGED_IN, true);
                        editor.commit();

                        startActivity(new Intent(LoginActivity.this, PatientSummaryInfoActivity.class));
                        finish();
                    }
                } else {
                    dialog.dismiss();
                    AppUtil.showSimpleDialog(LoginActivity.this, getString(R.string.server_error),
                            getString(R.string.could_not_connect_to_server));
                }

            }

            @Override
            public void onFailure(Call call, Throwable t) {
                dialog.dismiss();
                AppUtil.showSimpleDialog(LoginActivity.this,getString(R.string.server_error), t.getMessage());
            }

        });
    }