code: public static SwapFile get(final File parent, final String child) throws IOException
     {
  
        return get(parent, child, SpoolConfig.getDefaultSpoolConfig().fileCleaner);
     }
docs: Obtain SwapFile by parent file and name.
  
  @param parent
  - parent File
  @param child
  - String with file name
  @return SwapFile swap file
  @throws IOException
  I/O error