Unzipping Files with Android (Programmatically)

This article is about how to write a utility class for extracting files and directories in a compressed zip archive, using built-in Java API.

The java.util.zip package provides the following classes for extracting files and directories from a ZIP archive:

ZipInputStream: this is the main class which can be used for reading zip file and extracting files and directories (entries) within the archive. Here are some important usages of this class:
-read a zip via its constructor ZipInputStream(FileInputStream)
-read entries of files and directories via method getNextEntry()
-read binary data of current entry via method read(byte)
-close current entry via method closeEntry()
-close the zip file via method close()

ZipEntry: this class represents an entry in the zip file. Each file or directory is represented as a ZipEntry object. Its method getName() returns a String which represents path of the file/directory. The path is in the following form:
folder_1/subfolder_1/subfolder_2/…/subfolder_n/file.ext

Based on the path of a ZipEntry, we re-create directory structure when extracting the zip file.

Below class is used for unzip download zip and extract file and store your desire location.

public class UnzipUtil
  {
     private String zipFile;
     private String location;

  public UnzipUtil(String zipFile, String location)
  {
     this.zipFile = zipFile;
     this.location = location;

     dirChecker("");
  }

  public void unzip()
 {
   try
 {
      FileInputStream fin = new FileInputStream(zipFile);
      ZipInputStream zin = new ZipInputStream(fin);
      ZipEntry ze = null;
      while ((ze = zin.getNextEntry()) != null)
      {
       Log.v("Decompress", "Unzipping " + ze.getName());

if(ze.isDirectory())
{
 dirChecker(ze.getName());
}
else
{
 FileOutputStream fout = new FileOutputStream(location + ze.getName());     

 byte[] buffer = new byte[8192];
 int len;
 while ((len = zin.read(buffer)) != -1)
 {
  fout.write(buffer, 0, len);
 }
 fout.close();

 zin.closeEntry();

}

    }
      zin.close();
    }
     catch(Exception e)
     {
          Log.e("Decompress", "unzip", e);
     }

  }

   private void dirChecker(String dir)
   {
         File f = new File(location + dir);
         if(!f.isDirectory())
          {
            f.mkdirs();
          }
         }
    }

 public class MainActivity extends Activity
        {
        private ProgressDialog mProgressDialog;

        String Url="http://hasmukh/hb.zip";
        String unzipLocation = Environment.getExternalStorageDirectory() + "/unzipFolder/";
        String StorezipFileLocation =Environment.getExternalStorageDirectory() +                       "/DownloadedZip"; 
       String DirectoryName=Environment.getExternalStorageDirectory() + "/unzipFolder/files/";

       @Override
       protected void onCreate(Bundle savedInstanceState)
       {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.main);

           DownloadZipfile mew = new DownloadZipfile();
            mew.execute(url);

        }

        //-This is method is used for Download Zip file from server and store in Desire location.
        class DownloadZipfile extends AsyncTask<String, String, String>
         {
         String result ="";
          @Override
          protected void onPreExecute()
          {
            super.onPreExecute();
            mProgressDialog = new ProgressDialog(MainActivity.this);
            mProgressDialog.setMessage("Downloading...");
            mProgressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
            mProgressDialog.setCancelable(false);
            mProgressDialog.show();
            }

             @Override
             protected String doInBackground(String... aurl)
             {
              int count;

                    try
          {
URL url = new URL(aurl[0]);
URLConnection conexion = url.openConnection();
conexion.connect();
int lenghtOfFile = conexion.getContentLength();
InputStream input = new BufferedInputStream(url.openStream());

OutputStream output = new FileOutputStream(StorezipFileLocation);

byte data[] = new byte[1024];
long total = 0;

while ((count = input.read(data)) != -1)
{
 total += count;
 publishProgress(""+(int)((total*100)/lenghtOfFile));
 output.write(data, 0, count);
}
output.close();
input.close();
result = "true";

         } catch (Exception e) {

         result = "false";
         }
        return null;

       }
        protected void onProgressUpdate(String... progress)
        {
        Log.d("ANDRO_ASYNC",progress[0]);
        mProgressDialog.setProgress(Integer.parseInt(progress[0]));
        }

         @Override
         protected void onPostExecute(String unused)
         {
               mProgressDialog.dismiss();
               if(result.equalsIgnoreCase("true"))
         {
          try
             {
                unzip();
                   } catch (IOException e)
                   {
                 // TODO Auto-generated catch block
              e.printStackTrace();
              }
                 }
                     else
                   {

                   }
                       }
               }
          //This is the method for unzip file which is store your location. And unzip folder will                 store as per your desire location.



             public void unzip() throws IOException 
            {
            mProgressDialog = new ProgressDialog(MainActivity.this);
            mProgressDialog.setMessage("Please Wait...");
            mProgressDialog.setProgressStyle(ProgressDialog.STYLE_SPINNER);
            mProgressDialog.setCancelable(false);
            mProgressDialog.show();
            new UnZipTask().execute(StorezipFileLocation, DirectoryName);
              }


          private class UnZipTask extends AsyncTask<String, Void, Boolean> 
          {
          @SuppressWarnings("rawtypes")
          @Override
          protected Boolean doInBackground(String... params) 
          {
             String filePath = params[0];
             String destinationPath = params[1];

               File archive = new File(filePath);
                try 
                 {
                 ZipFile zipfile = new ZipFile(archive);
                 for (Enumeration e = zipfile.entries(); e.hasMoreElements();) 
                 {
                         ZipEntry entry = (ZipEntry) e.nextElement();
                         unzipEntry(zipfile, entry, destinationPath);
                    }


         UnzipUtil d = new UnzipUtil(StorezipFileLocation, DirectoryName); 
         d.unzip();

            } 
    catch (Exception e) 
         {
           return false;
         }

          return true;
       }

           @Override
           protected void onPostExecute(Boolean result) 
           {
                mProgressDialog.dismiss(); 

             }


            private void unzipEntry(ZipFile zipfile, ZipEntry entry,String outputDir) throws IOException 
         {

                  if (entry.isDirectory()) 
        {
                createDir(new File(outputDir, entry.getName()));
                return;
          }

           File outputFile = new File(outputDir, entry.getName());
           if (!outputFile.getParentFile().exists())
           {
              createDir(outputFile.getParentFile());
           }

           // Log.v("", "Extracting: " + entry);
          BufferedInputStream inputStream = new BufferedInputStream(zipfile.getInputStream(entry));
          BufferedOutputStream outputStream = new BufferedOutputStream(new FileOutputStream(outputFile));

       try 
        {

         }
       finally 
         {
              outputStream.flush();
              outputStream.close();
              inputStream.close();
          }
           }

             private void createDir(File dir) 
             {
                if (dir.exists()) 
              {
                   return;
                  }
                    if (!dir.mkdirs()) 
                      {
                        throw new RuntimeException("Can not create dir " + dir);
               }
               }}
                 }

            Note: Do not forgot to add below  permission in android Manifest.xml file.

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

I will be happy if you will provide your feedback or follow this blog. Any suggestion and help will be appreciated.
Thank you :)