Retrofit Connection Manager Boilerplate

ConnectionManager.java

package com.newecon.qounter.connection;

import ?.API;

import java.io.IOException;

import okhttp3.Interceptor;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;
import okhttp3.logging.HttpLoggingInterceptor;
import retrofit2.Retrofit;
import retrofit2.adapter.rxjava2.RxJava2CallAdapterFactory;
import retrofit2.converter.gson.GsonConverterFactory;

/**
 * Created by Danny on 10-09-2017.
 */

public class ConnectionManager {
    private static final ConnectionManager conManager = new ConnectionManager();
    private static API client;
    private static Retrofit retrofit;
    private static final String BASE_URL = "https://api.danysam.net";

    public static ConnectionManager getInstance() {
        return conManager;
    }

    private ConnectionManager() {

        HttpLoggingInterceptor logging = new HttpLoggingInterceptor();
        logging.setLevel(HttpLoggingInterceptor.Level.BODY);

        OkHttpClient.Builder httpClient = new OkHttpClient.Builder();

        httpClient.addInterceptor(new Interceptor() {
            @Override
            public Response intercept(Chain chain) throws IOException {
                Request baseRequest = chain.request();

                Request headerRequest = baseRequest.newBuilder()
                        .header("Content-Type", "application/json")
                        .method(baseRequest.method(), baseRequest.body())
                        .build();

                return chain.proceed(headerRequest);
            }
        });

        // add logging as last interceptor
        httpClient.addInterceptor(logging);

        Retrofit.Builder builder = new Retrofit.Builder()
                .baseUrl(BASE_URL)
                .addConverterFactory(GsonConverterFactory.create())
                .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
                .client(httpClient.build());

        retrofit = builder.build();

        client = retrofit.create(API.class);

    }

    public API getClient() {
        return client;
    }

    public Retrofit getRetrofit() {
        return retrofit;
    }

}