public void loadImageUrls() {
        try {
            List<String> lines = Files.readAllLines(Paths.get(MainClass.URLS_FILE), Charset.forName("UTF-8"));

            for (String url : lines) {
                downloadedUrls.put(url, Boolean.TRUE);
            }
        } catch (IOException ex) {
            File urlsFile = new File(MainClass.URLS_FILE);
            if (!urlsFile.exists()) {
                try {
                    urlsFile.createNewFile();
                } catch (IOException ex1) {
                    Logger.getLogger(NBFrame.class.getName()).log(Level.SEVERE, null, ex1);
                }
            }
        }

    }