/**
     * Constructs a new JodExtractor and initializes the extension and extractor mappings.
     */
    public JodExtractor() {
        extensionMap.put("", "txt");
        // Text Formats
        extensionMap.put("odt", "txt");
        extensionMap.put("ott", "txt");
        extensionMap.put("sxw", "txt");
        extensionMap.put("rtf", "txt");
        extensionMap.put("doc", "txt");
        extensionMap.put("docx", "txt");

application/vnd.openxmlformats-officedocument.spreadsheetml.sheet=excel\n\
application/vnd.ms-powerpoint=powerpoint\n\
application/vnd.openxmlformats-officedocument.presentationml.presentation=powerpoint\n\
application/vnd.oasis.opendocument.text=odt\n\
application/vnd.oasis.opendocument.spreadsheet=ods\n\
application/vnd.oasis.opendocument.presentation=odp\n\
application/pdf=pdf\n\
application/x-fictionbook+xml=fb2\n\
application/e-pub+zip=epub\n\

     * application/vnd.ms-powerpoint=powerpoint<br>
     * application/vnd.openxmlformats-officedocument.presentationml.presentation=powerpoint<br>
     * application/vnd.oasis.opendocument.text=odt<br>
     * application/vnd.oasis.opendocument.spreadsheet=ods<br>
     * application/vnd.oasis.opendocument.presentation=odp<br>
     * application/pdf=pdf<br>
     * application/x-fictionbook+xml=fb2<br>