code = "";
        value = FessFunctions.formatCode("L", "prettyprint", "text/plain", code);
        assertEquals("<pre class=\"prettyprint\"></pre>", value);

        code = "aaa";
        value = FessFunctions.formatCode("L", "prettyprint", "text/plain", code);
        assertEquals("<pre class=\"prettyprint\">aaa</pre>", value);

        code = "aaa\nbbb";
        value = FessFunctions.formatCode("L", "prettyprint", "text/plain", code);

  </function>

  <function>
    <description>Format a content as code.</description>
    <name>formatCode</name>
    <function-class>org.codelibs.fess.taglib.FessFunctions</function-class>
    <function-signature>java.lang.String formatCode(java.lang.String, java.lang.String, java.lang.String, java.lang.String)</function-signature>

        if (input == null) {
            return StringUtil.EMPTY;
        }
        return input.toString().replaceAll(regex, replacement);
    }

    public static String formatCode(final String prefix, final String style, final String mimetype, final String input) {
        if (input == null) {
            return StringUtil.EMPTY;
        }