token Header

OkHttpClient client = new OkHttpClient.Builder().addInterceptor(new Interceptor() {
      @Override
      public Response intercept(Chain chain) throws IOException {
        Request newRequest  = chain.request().newBuilder()
            .addHeader("Authorization", "Bearer " + token)
            .build();
        return chain.proceed(newRequest);
      }
    }).build();

Retrofit retrofit = new Retrofit.Builder()
    .client(client)
    .baseUrl(/** your url **/)
    .addConverterFactory(GsonConverterFactory.create())
    .build();