Fast deserialization of really big JSON responses

public class LoadData extends AsyncTask {
	String _url="";
	public LoadData(String url){
		_url=url;
	}
	@Override
	protected Void doInBackground(Void... voids) {
		try {
			//скачивание данных
			HttpClient httpclient = new DefaultHttpClient();
			HttpPost httppost = new HttpPost(_url);
			HttpResponse response = httpclient.execute(httppost);
			HttpEntity httpEntity=response.getEntity();
			InputStream stream = AndroidHttpClient.getUngzippedContent(httpEntity); //для скачивания gzip-нутых данных
			BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(stream));
			StringBuilder responseBuilder= new StringBuilder();
			char[] buff = new char[1024*512];
			int read;
			while((read = bufferedReader.read(buff)) != -1) {
				responseBuilder.append(buff, 0, read) ;
				Log.d("скачано " + PrepareSize(responseBuilder.length()));
			}
			//парсинг полученных данных
			HumorItems list= Gson.fromJson(responseBuilder.toString(),HumorItems.class);
			//тестовый вывод
			for (HumorItem message:list.Items){
				Log.d("Текст: "+message.text);
				Log.d("Ссылка: "+message.url);
				Log.d("-------------------");
			}
			Log.d("ВСЕГО СКАЧАНО "+list.Items.size());
		} catch (IOException e) {
			e.printStackTrace();
			Log.e("ошибка "+e.getMessage());
		}
		return null;
	}
}

public class Log {
    public static final String TAG="hhh";
    public static void d(String text){
        android.util.Log.d(TAG,text);
    }
    public static void e(String text){
        android.util.Log.e(TAG,text);
    }
}
    public String PrepareSize(long size){
        if (size<1024){
            return size+" б.";
        }else
        {
            return size/1024+" кб.";
        }
    }

public class LoadBigDataTmpFile extends AsyncTask {
        String _url="";
        File cache_dir;
        public LoadBigDataTmpFile(String url){
            _url=url;
            cache_dir = getExternalCacheDir();
        }
        @Override
        protected Void doInBackground(Void... voids) {
            try {
                //скачивание данных
                HttpClient httpclient = new DefaultHttpClient();
                HttpPost httppost = new HttpPost(_url);
                HttpResponse response = httpclient.execute(httppost);	
                HttpEntity httpEntity=response.getEntity();
                InputStream stream = AndroidHttpClient.getUngzippedContent(httpEntity);
                //нечто новое - открываем временный файл для записи
                BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(stream));
                File file = new File(cache_dir, "temp_json_new.json");
                if (file.exists()){ //если таковой уже есть - удаляем и создаём новый
                    file.delete();
                }
                file.createNewFile();
                FileOutputStream fileOutputStream=new FileOutputStream(file,true);
                BufferedWriter bufferedWriter=new BufferedWriter(new OutputStreamWriter(fileOutputStream));
                char[] buff = new char[1024*1024];
                int read;
                long FullSize=0;
                while((read = bufferedReader.read(buff)) != -1) {
                    bufferedWriter.write(buff,0,read);	//запись в файл
                    FullSize+=read;
                    Log.d("скачано " + PrepareSize(FullSize));
                }
                bufferedWriter.flush();
                fileOutputStream.close();
                //парсинг из файла
                Log.d("начали парсинг...");
                FileInputStream fileInputStream=new FileInputStream(file);
                InputStreamReader reader = new InputStreamReader(fileInputStream);
                HumorItems list= Gson.fromJson(reader,HumorItems.class);
                Log.d("закончили парсинг.");
                /тестовый вывод
                for (HumorItem message:list.Items){
                                Log.d("Текст: "+message.text);
                                Log.d("Ссылка: "+message.url);
                                Log.d("-------------------");
                }
                Log.d("ВСЕГО СКАЧАНО "+list.Items.size());
            } catch (IOException e) {
                e.printStackTrace();
                Log.e("ошибка "+e.getMessage());
            }
            return null;
        }
    }

public class LoadBigData extends AsyncTask {
	String _url="";
	public LoadBigData(String url){
		_url=url;
	}
	@Override
	protected Void doInBackground(Void... voids) {
		try {
			//скачивание данных
			HttpClient httpclient = new DefaultHttpClient();
			HttpPost httppost = new HttpPost(_url);
			HttpResponse response = httpclient.execute(httppost);
			HttpEntity httpEntity=response.getEntity();
			InputStream stream = AndroidHttpClient.getUngzippedContent(httpEntity);
			//открывам потом на чтение данных
			BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(stream));
			//и сразу направляем его в десериализатор
			InputStreamReader reader = new InputStreamReader(stream);
			HumorItems list= Gson.fromJson(reader,HumorItems.class);
			//тестовый вывод
			for (HumorItem message:list.Items){
				Log.d("Текст: "+message.text);
				Log.d("Ссылка: "+message.url);
				Log.d("-------------------");
			}
			Log.d("ВСЕГО СКАЧАНО "+list.Items.size());
		} catch (IOException e) {
			e.printStackTrace();
			Log.e("ошибка "+e.getMessage());
		}
		return null;
	}
}