code: public static File createTempDirectory(String prefix) {
  	File temp = null;
  	
  	try {
  	  temp = File.createTempFile(prefix != null ? prefix : "temp", Long.toString(System.nanoTime()));
  	
  	  if (!(temp.delete())) {
  	    throw new IOException("Could not delete temp file: "
  		  + temp.getAbsolutePath());
  	  }
  	
  	  if (!(temp.mkdir())) {
  	    throw new IOException("Could not create temp directory: "
  	      + temp.getAbsolutePath());
  	  }
  	} catch (IOException e) {
  	  throw new DukeException("Unable to create temporary directory with prefix " + prefix, e);
  	}
  	
  	return temp;
    }
docs: Creates a temporary folder using the given prefix to generate its name.
  @param prefix the prefix string to be used in generating the directory's name; may be <i>null</i>
  @return the <code>File</code> to the newly created folder
  @throws IOException