How to upgrade APK with Android parsing XML files

public class DownLoadApk {
 public static SharedPreferences sharedPrederences = null;
 //Start the installation interface public static void DownId(Context context, long downId){
  DownloadManager mDownloadManager = (DownloadManager) (Context.DOWNLOAD_SERVICE);
  Uri downloadUri = (downId);
  startInstall(context, downloadUri);
 }
 /**
   * Jump to the installation interface
   * @param context scope
   * @param uri Package Name
   */
 private static void startInstall(Context context, Uri uri) {
  Intent install = new Intent(Intent.ACTION_VIEW);
  (uri, "application/-archive");
  (Intent.FLAG_ACTIVITY_NEW_TASK);
  (install);
 }
 //Delete the file public static boolean fileDelete(String filePath) {
  File file = new File(filePath);
  if (() == false) {
   return false;
  }
  return ();
 }

Thread thread = new Thread() {
 @Override
 public void run() {
  ();
  //The address of XML stored in the ftp server  String path = FileUtils.getDevice_address()+"";
  try {
   URL url = new URL(path);
   HttpURLConnection conn = (HttpURLConnection) url
     .openConnection();
   ("GET");
   (5000);
   (5000);
   //Send http GET request and get the corresponding code   if (() == 200) {
    InputStream is = ();
    // Use the pull parser to start parsing this stream    parseNewsXml(is);
   }
  } catch (Exception e) {
   // TODO Auto-generated catch block
   ();
  }
 }
};
(); 

private void parseNewsXml(InputStream is) {
 XmlPullParser xp = ();
 try {
  (is, "utf-8");
  //Judge the event type of the node and you can know what node the current node is  int type = ();
  News news = null;
  while (type != XmlPullParser.END_DOCUMENT) {
   switch (type) {
    case XmlPullParser.START_TAG:
     if ("newslist".equals(())) {
      newsList = new ArrayList<>();
      break;
     } else if ("news".equals(())) {
      news = new News();
      break;
     } else if ("name".equals(())) {
      String name = ();
      (name);
      break;
     } else if ("code".equals(())) {
      String code = ();
      (code);
      break;
     }
    case XmlPullParser.END_TAG:
     if ("news".equals(())) {
      (news);
     }
     break;
     default:
     break;
   }
   //After parsing the current node, move the pointer to the next node until the node is finished and return its event type   type = ();
  }
  // Send a message  (1);
 } catch (Exception e) {
  ();
 }
}

//Get the download managerDownloadManager manager =(DownloadManager)(mContext.DOWNLOAD_SERVICE);
handler = new Handler() {
 @Override
 public void handleMessage(Message msg) {
  (msg);
  News news = (0);
  ("aii", "XML: "+()+"，apk:"+getPackageInfo(mContext));
  if((())>(getPackageInfo(mContext))){
   if(dowmCliek) {
    //Open the progress bar thread    isRun = true;
    dowmCliek = false;
    //Delete the original installation package before updating the APK    (path + "/" + mAPK);
    //Create a download request     down = new (
      (mWebsite));
    //Set the allowed network type, here are both mobile network and wifi    (.NETWORK_MOBILE | .NETWORK_WIFI);
    //Not issued notifications, both background downloads    (true);
    //Do not display the download interface    (true);
    //title    (mContext, null, "XXX is upgrading...");
    //Put the download request into the queue and return the download id    downId = (down);
   }else{
    (mContext,"Upgrading...",Toast.LENGTH_SHORT).show();
   }
  }else{
    (mContext,"It's the latest version, no need to upgrade...",Toast.LENGTH_SHORT).show();
  }
 }
};

//Timed tasksScheduledExecutorService scheduledExecutorService = (1);
(new Runnable() {
   @Override
   public void run() {
    if(isRun) {
     Message msg = ();
      = 1;
     (msg);
    }
   }
  }, 0, 100, );//Delay 0, interval 100, unit millisecondsprivate Handler mHandler = new Handler(new () {
 @Override
 public boolean handleMessage(Message msg) {
  switch () {
   case 1:
    //android download manager     query = new ().setFilterById(downId);
    Cursor cursor = (query);
    if (cursor != null && ()) {
     //Search the file size directly here     long downSize = ((
       DownloadManager.COLUMN_TOTAL_SIZE_BYTES));
     //Get the total file download size     fileTotalSize =((
       DownloadManager.COLUMN_BYTES_DOWNLOADED_SO_FAR));
     ();

     ("Print", "Total Size" + downSize);
     ("Print", "Download Progress" + fileTotalSize);
     if (fileTotalSize>0) {
      NumberFormat numberFormat = ();
      (2);
      String result = ((float)fileTotalSize/(float)downSize*100);
      ("Print", "downloaded size: " + result+"%");
      (result+"%");
     }
     //Downloaded     if(fileTotalSize==downSize) {
      isRun = false;
      ("Click to upgrade");
     }
    }
  }
  return true;
 }
});

DownloadCompleteReceiver receiver = new DownloadCompleteReceiver();
//Broadcast after downloadingclass DownloadCompleteReceiver extends BroadcastReceiver {
 @Override
 public void onReceive(Context context, Intent intent) {
  if(().equals(DownloadManager.ACTION_DOWNLOAD_COMPLETE)){
   long downId = (DownloadManager.EXTRA_DOWNLOAD_ID, -1);
   if(downId!=-1) {
    //Start the installation    (context,downId);
    dowmCliek=true;
   }
  }else{
   (context, ()+"Download failed", Toast.LENGTH_SHORT).show();
  }
 }
}
//Start download and complete broadcast(receiver, new IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE));

private static String getPackageInfo(Context context) {
 PackageInfo pi = null;
 try {
  PackageManager pm = ();
  pi = ((),
    PackageManager.GET_CONFIGURATIONS);
  return +"";
 } catch (Exception e) {
  ();
 }
 return null;
}