private Transformer buildTransformer(String name, File xslDir, TransformerFactory tf)
      throws Exception {

    Transformer tr =
        tf.newTransformer(
            new StreamSource(
                new FileReader(xslDir.getAbsolutePath() + File.separatorChar + name + ".xsl")));
    tr.setOutputProperty(OutputKeys.INDENT, "yes");
    tr.setOutputProperty(OutputKeys.METHOD, "html");
    tr.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "3");

    return tr;
  }
  public void init(ServletConfig config) throws ServletException {
    super.init(config);
    context = config.getServletContext();

    TextProcessor tp = new CaseFolder();

    try {
      wikipedia =
          new Wikipedia(
              context.getInitParameter("mysql_server"),
              context.getInitParameter("mysql_database"),
              context.getInitParameter("mysql_user"),
              context.getInitParameter("mysql_password"));
    } catch (Exception e) {
      throw new ServletException("Could not connect to wikipedia database.");
    }

    // Escaper escaper = new Escaper() ;

    definer = new Definer(this);
    comparer = new Comparer(this);
    searcher = new Searcher(this);

    try {
      wikifier = new Wikifier(this, tp);

    } catch (Exception e) {
      System.err.println("Could not initialize wikifier");
    }

    try {
      File dataDirectory = new File(context.getInitParameter("data_directory"));

      if (!dataDirectory.exists() || !dataDirectory.isDirectory()) {
        throw new Exception();
      }

      cachingThread = new CacherThread(dataDirectory, tp);
      cachingThread.start();
    } catch (Exception e) {
      throw new ServletException("Could not locate wikipedia data directory.");
    }

    try {
      TransformerFactory tf = TransformerFactory.newInstance();

      transformersByName = new HashMap<String, Transformer>();
      transformersByName.put(
          "help", buildTransformer("help", new File("/research/wikipediaminer/web/xsl"), tf));
      transformersByName.put(
          "loading", buildTransformer("loading", new File("/research/wikipediaminer/web/xsl"), tf));
      transformersByName.put(
          "search", buildTransformer("search", new File("/research/wikipediaminer/web/xsl"), tf));
      transformersByName.put(
          "compare", buildTransformer("compare", new File("/research/wikipediaminer/web/xsl"), tf));
      transformersByName.put(
          "wikify", buildTransformer("wikify", new File("/research/wikipediaminer/web/xsl"), tf));

      Transformer serializer = TransformerFactory.newInstance().newTransformer();
      serializer.setOutputProperty(OutputKeys.INDENT, "yes");
      serializer.setOutputProperty(OutputKeys.METHOD, "xml");
      serializer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "3");
      transformersByName.put("serializer", serializer);

    } catch (Exception e) {
      throw new ServletException("Could not load xslt library.");
    }
  }