code: public static File createTempFile(String prefix, String suffix) throws IOException {
          return createTempFile(prefix, suffix, null);
      }
docs: Creates an empty temporary file using the given prefix and suffix as part
  of the file name. If {@code suffix} is null, {@code .tmp} is used. This
  method is a convenience method that calls
  {@link #createTempFile(String, String, File)} with the third argument
  being {@code null}.
  
  @param prefix
  the prefix to the temp file name.
  @param suffix
  the suffix to the temp file name.
  @return the temporary file.
  @throws IOException
  if an error occurs when writing the file.