code: public void rollback() throws BackupException
     {
        try
        {
           SecurityHelper.doPrivilegedIOExceptionAction(new PrivilegedExceptionAction<Void>()
           {
              public Void run() throws IOException
              {
                 for (int i = 0; i < tmpDirs.size(); i++)
                 {
                    File tmpDir = tmpDirs.get(i);
                    File dataDir = dataDirs.get(i);
  
                    if (dataDir.exists())
                    {
                       DirectoryHelper.removeDirectory(dataDir);
                    }
  
                    DirectoryHelper.copyDirectory(tmpDir, dataDir);
                 }
  
                 return null;
              }
           });
        }
        catch (IOException e)
        {
           throw new BackupException(e);
        }
     }
docs: {@inheritDoc}