/**
 * Early Return Style Gauntlet
 * to delete a directory
 *
 * @param dirname name of the directory to delete
 * @return true if it was successfully deleted.
 */
boolean deleteDir ( String dirname )
   {
   if ( dirname == null ) return false;
   File dirFile = new File( dirname);
   if ( ! dirFile.exists() ) return false;
   if ( ! dirFile.isDirectory() ) return false;
   // ensure directory empty
   if ( dirFile.list().length != 0 ) return false;
   return dirFile.delete();
   }