code: private File[] getSubDirectories(File parent) throws IOException {
          return parent.listFiles(new FileFilter() { // Can return null if there are no events
              public boolean accept(File file) {
                  return file.isDirectory();
              }
          });
      }
docs: Gets an array containing all of the sub-directories in the given parent directory.
  
  @param parent The directory from which to get sub-directories.
  @return An array of sub-directories.
  @throws IOException If there is an error listing the files in the directory.