java - How to Zip a folders and download -

i have implemented download of files. downloading , saving memory.

now problem is, if there folder , sub folder, need zip folder , download zip file , save in memory. tried lot did'nt find solution. can 1 can guide me solution?

here download single file code...

@override     protected string doinbackground(string... surl) {         inputstream input = null;         outputstream output = null;         zipoutputstream zos = null;         httpurlconnection connection = null;         try {             url url = new url(surl[0]);             connection = (httpurlconnection) url.openconnection();             connection.connect();              if (connection.getresponsecode() != httpurlconnection.http_ok) {                 return "server returned http "                         + connection.getresponsecode() + " "                         + connection.getresponsemessage();             }              string filename = tvtitle.gettext().tostring();             string fileextension = tvtype.gettext().tostring();              file imagedirectory = new file(path);             imagedirectory.mkdirs();             int filelength = connection.getcontentlength();             string _path = path;             input = connection.getinputstream();             file outputfile = new file(_path, filename + fileextension);             output = new fileoutputstream(outputfile);             // zos = new zipoutputstream(output);              byte data[] = new byte[4096];             long total = 0;             int count;             while ((count = input.read(data)) != -1) {                  if (iscancelled()) {                     input.close();                     return null;                 }                 total += count;                  if (filelength > 0) // if total length known                     publishprogress((int) (total * 100 / filelength));                 output.write(data, 0, count);             }         } catch (exception e) {             return e.tostring();         } {             try {                 if (output != null)                     output.close();                 if (input != null)                     input.close();             } catch (ioexception ignored) {             }              if (connection != null)                 connection.disconnect();         }         return null;     } 

first add permission in manifest

<uses-permission android:name="android.permission.write_external_storage"/> 

call method passing "inputfolderpath" , "outputfolderpath"

private static void zipfolder(string inputfolderpath, string outzippath)  { try {     fileoutputstream fos = new fileoutputstream(outzippath);     zipoutputstream zos = new zipoutputstream(fos);     file srcfile = new file(inputfolderpath);     file[] files = srcfile.listfiles();     log.d("", "zip directory: " + srcfile.getname());     (int = 0; < files.length; i++) {         log.d("", "adding file: " + files[i].getname());         byte[] buffer = new byte[1024];         fileinputstream fis = new fileinputstream(files[i]);         zos.putnextentry(new zipentry(files[i].getname()));         int length;         while ((length = fis.read(buffer)) > 0) {             zos.write(buffer, 0, length);         }         zos.closeentry();         fis.close();     }     zos.close(); } catch (ioexception ioe) {     log.e("", ioe.getmessage()); } }