Android : Run several AsyncTask in Adroid but only when bofore task has been terminated

I need to run several times the same AsyncTask in Android (passing a different file parameter to download from FTP server), but I need one after other, not in parallel, just do this one when the other one has been terminated/finished.

So far I have this code, but it's no working properly, last task never ends:

    private class FtpTask extends AsyncTask<String, Void, Integer> {
        private String msg = "";
        private String bean = "";

        public FtpTask(String msg, String bean) {
            this.msg = msg;
            this.bean = bean;
        }

        protected void onPreExecute() {
            showProgress(true, "Syncronizing", "Processing " + msg + ", wait...");
        }

        @Override
        protected Integer doInBackground(String... params) {
            if (bean.trim().equals("")) {
                bean = params[0];
            }
            String file = Util.getMapFiles().get(bean);
            int total = 0;
            try {
                FtpServerUtil ftp = new FtpServerUtil();
                ArrayList<String> fileRows = ftp.lerArquivo(file);
                total = insertRecords(bean, fileRows);
            } catch (IOException e) {
                Log.e(Const.TAG, "Lendo arquivo no FTP", e);
            }
            if (total > 0) {
                Util.setSharedPrefValue("data_sinc_" + bean.toLowerCase(), Util.dateTimeToStringBR(null), context);
            }
            return total;
        }

        protected void onPostExecute(Integer total) {
            showProgress(false, null, null);
            String msg = "";
            if (total > 0) {
                msg = total + " records [" + bean + "] sincronized";
            } else {
                msg = "No records...";
            }
            Util.showToast(msg, activity);
        }
    }
...
@TargetApi(Build.VERSION_CODES.HONEYCOMB)
    private void StartAsyncTaskInParallel(FtpTask task) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
            task.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
        } else {
            task.execute();
        }
    }

..
FtpTask ftpTask1 = new FtpTask("Clientes","Cliente");
FtpTask ftpTask2 = new FtpTask("Médicos","Medico");
StartAsyncTaskInParallel(ftpTask1);
StartAsyncTaskInParallel(ftpTask2);

How could I achieve that?