code: public static final StyleSheet getUsedStyles(Document doc, String encoding, URL base, MediaSpec media)
      {
          return getUsedStyles(doc, encoding, base, media, getNetworkProcessor());
      }
docs: This is the same as {@link CSSFactory#getUsedStyles(Document, String, URL, MediaSpec)} with
  the possibility of specifying a custom network processor.
  
  @param doc
  DOM tree
  @param encoding
  The default encoding used for the referenced style sheets
  @param base
  Base URL against which all files are searched
  @param media
  Selected media for style sheet
  @return the rules of all the style sheets used in the document including the inline styles