同时进行多个Web呼叫

Question

我有一个异步任务，如果成功生成其他5个网络门户，则会记录用户。截至目前，它在一个异步任务（一次一个）中完成所有工作。如何让它们同时进行。

这是我的代码，用于了解我到目前为止所拥有的内容：

public class UserLoginTask extends AsyncTask<Void, Void, Boolean> {
        @Override
        protected Boolean doInBackground(Void... params) {
            HttpClient httpclient = new DefaultHttpClient();
            HttpClientHandler.httpClient = httpclient;
 HttpPost httppost = new HttpPost(Constants.BASEURL
                    + "login.pl");

            try {
                List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(
                        2);
                nameValuePairs.add(new BasicNameValuePair("userid", mEmail));
                nameValuePairs
                        .add(new BasicNameValuePair("password", mPassword));

                httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));

                HttpResponse response = httpclient.execute(httppost);
                String responseAsText = EntityUtils.toString(response
                        .getEntity());

                jsonStr = responseAsText.toString();
                if (jsonStr != null) {
                    try {
                        JSONObject jsonObj = new JSONObject(jsonStr);
                        d = jsonObj.getJSONObject(TAG_D);
                        success = d.getString(TAG_SUCCESS);
                        error = d.getString(TAG_ERROR);

                    } catch (JSONException e) {
                        runOnUiThread(new Runnable() {
                            public void run() {
                                error = null;
                                down = true;

                            }
                        });
                        return false;
                    }
                } else {
                    Log.e("ServiceHandler",
                            "Couldn't get any data from the url");
                }

            } catch (ClientProtocolException e) {

            } catch (IOException e) {

            } 

            if (success == "true") {
      httppost = new HttpPost(Constants.BASEURL + "drivers.pl");
                try {
                    // set entities here ...

                    HttpResponse response = httpclient.execute(httppost);
                    String responseAsText = EntityUtils.toString(response
                            .getEntity());

                    String driverJson = responseAsText.toString();
                    ...